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Sunday, October 6, 2019

Python Qt5 : the drag and drop feature.

Today I tested drag and drop feature with PyQt5.
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
This is a simple example using setAcceptDrops and setDragEnabled:
import sys
from PyQt5.QtWidgets import QApplication, QWidget, QListWidget, QHBoxLayout,QListWidgetItem
from PyQt5.QtGui import QIcon

class Window(QWidget):
    def __init__(self):
        super().__init__()

        self.myListWidget1 = QListWidget()
        self.myListWidget2 = QListWidget()
        self.myListWidget2.setViewMode(QListWidget.IconMode)
        self.myListWidget1.setAcceptDrops(True)
        self.myListWidget1.setDragEnabled(True)
        self.myListWidget2.setAcceptDrops(True)
        self.myListWidget2.setDragEnabled(True)
        self.setGeometry(480, 400, 640, 480)
        self.myLayout = QHBoxLayout()
        self.myLayout.addWidget(self.myListWidget1)
        self.myLayout.addWidget(self.myListWidget2)

        l1 = QListWidgetItem(QIcon('house.png'), "House")
        l2 = QListWidgetItem(QIcon('cloud.png'), "Clouds ")
        l3 = QListWidgetItem(QIcon('user.png'), "User")
        l4 = QListWidgetItem(QIcon('save.png'), "Save")

        self.myListWidget1.insertItem(1, l1)
        self.myListWidget1.insertItem(2, l2)
        self.myListWidget1.insertItem(3, l3)
        self.myListWidget1.insertItem(4, l4)

        QListWidgetItem(QIcon('house.png'), "House", self.
                        myListWidget2)
        QListWidgetItem(QIcon('cloud.png'), "Clouds", self.
                        myListWidget2)
        QListWidgetItem(QIcon('save.png'), "Save", self.
                        myListWidget2)

        self.setWindowTitle('Example: Drag and Drop');
        self.setLayout(self.myLayout)

        self.show()

App = QApplication(sys.argv)
window = Window()
sys.exit(App.exec())
The result is a windows with two QListWidget with an drag and drop feature.

Wednesday, October 2, 2019

Python 3.7.4 : Using the paramiko pakage.

Today I tested the paramiko package.
First, I install and check the version of this package.
[mythcat@desk my_network_tools]$ pip3 install paramiko --user
Collecting paramiko
...
  Running setup.py install for pycparser ... done
Successfully installed asn1crypto-0.24.0 bcrypt-3.1.7 cffi-1.12.3 cryptography-2.7 paramiko-2.6.0
 pycparser-2.19 pynacl-1.3.0
[mythcat@desk my_network_tools]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import paramiko
>>> dir(paramiko)
['AUTH_FAILED', 'AUTH_PARTIALLY_SUCCESSFUL', 'AUTH_SUCCESSFUL', 'Agent', 'AgentKey', 'AuthHandler',
 'AuthenticationException', 'AutoAddPolicy', 'BadAuthenticationType', 'BadHostKeyException', 'BaseSFTP',
 'BufferedFile', 'Channel', 'ChannelException', 'ChannelFile', 'ChannelStderrFile', 'ChannelStdinFile',
 'DSSKey', 'ECDSAKey', 'Ed25519Key', 'GSSAuth', 'GSS_AUTH_AVAILABLE', 'GSS_EXCEPTIONS', 'HostKeys',
 'InteractiveQuery', 'Message', 'MissingHostKeyPolicy', 'OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED',
 'OPEN_FAILED_CONNECT_FAILED', 'OPEN_FAILED_RESOURCE_SHORTAGE', 'OPEN_FAILED_UNKNOWN_CHANNEL_TYPE',
 'OPEN_SUCCEEDED', 'PKey', 'Packetizer', 'PasswordRequiredException', 'ProxyCommand', 'ProxyCommandFailure',
 'PublicBlob', 'RSAKey', 'RejectPolicy', 'SFTP', 'SFTPAttributes', 'SFTPClient', 'SFTPError', 'SFTPFile',
 'SFTPHandle', 'SFTPServer', 'SFTPServerInterface', 'SFTP_BAD_MESSAGE', 'SFTP_CONNECTION_LOST', 'SFTP_EOF',
 'SFTP_FAILURE', 'SFTP_NO_CONNECTION', 'SFTP_NO_SUCH_FILE', 'SFTP_OK', 'SFTP_OP_UNSUPPORTED', 
'SFTP_PERMISSION_DENIED', 'SSHClient', 'SSHConfig', 'SSHException', 'SecurityOptions', 'ServerInterface',
 'SubsystemHandler', 'Transport', 'WarningPolicy', '__all__', '__author__', '__builtins__', '__cached__', 
'__doc__', '__file__', '__license__', '__loader__', '__name__', '__package__', '__path__', '__spec__', 
'__version__', '__version_info__', '_version', 'agent', 'auth_handler', 'ber', 'buffered_pipe', 'channel',
 'client', 'common', 'compress', 'config', 'dsskey', 'ecdsakey', 'ed25519key', 'file', 'hostkeys', 
'io_sleep', 'kex_curve25519', 'kex_ecdh_nist', 'kex_gex', 'kex_group1', 'kex_group14', 'kex_group16',
 'kex_gss', 'message', 'packet', 'pipe', 'pkey', 'primes', 'proxy', 'py3compat', 'rsakey', 'server', 
'sftp', 'sftp_attr', 'sftp_client', 'sftp_file', 'sftp_handle', 'sftp_server', 'sftp_si', 'ssh_exception',
 'ssh_gss', 'sys', 'transport', 'util']
>>> paramiko.__version__
'2.6.0'
The documentation for this version can be found at this webpage.
A simple example with this python package and ssh connection to 192.168.0.143 on port 22 can be see on the next source code
#!/usr/bin/env python
"""Return the ssh output with password connection and Linux commands"""
import paramiko

client = paramiko.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
conn= client.connect('192.168.0.143', port='22', username='mythcat', password='the_pass')
# Obtain session
session = client.get_transport().open_session()
print("| Retcode: "+str(session)+"|")

stdin, stdout, stderr=client.exec_command('sudo hostname;w')
save_stdout = stdout.readlines()
retcode = stdout.channel.recv_exit_status()

stdin, stdout, stderr=client.exec_command('ss -nap;')
save_stdout2 = stdout.readlines()
print(save_stdout,save_stdout2)
#for line in stdout:
#    print (line)

Tuesday, October 1, 2019

Python 3.7.4 : Install the protobuf from sources on Fedora distro.

Today I will show you how to build protobuf from sources using the Fedora distro.
The google team comes with this intro:
Protocol buffers are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data – think XML, but smaller, faster, and simpler...
This google project comes with these tutorials.
The GitHub project can be found here.
To install the compiler, download the package.
[mythcat@desk ~]$ cd Downloads/
[mythcat@desk Downloads]$ cp protobuf-python-3.9.2.tar.gz ~/
[mythcat@desk Downloads]$ cd ..
[mythcat@desk ~]$ tar xvzf protobuf-python-3.9.2.tar.gz 
...
protobuf-3.9.2/aclocal.m4
protobuf-3.9.2/install-sh
protobuf-3.9.2/generate_descriptor_proto.sh
protobuf-3.9.2/CHANGES.txt
protobuf-3.9.2/configure.ac
protobuf-3.9.2/configure
Let's see the content:
[mythcat@desk ~]$ cd protobuf-3.9.2/
[mythcat@desk protobuf-3.9.2]$ ls
aclocal.m4                   config.sub                    ltmain.sh            README.md
ar-lib                       configure                     m4                   six.BUILD
autogen.sh                   configure.ac                  Makefile.am          src
benchmarks                   conformance                   Makefile.in          test-driver
BUILD                        CONTRIBUTORS.txt              missing              third_party
CHANGES.txt                  depcomp                       objectivec           update_file_lists.sh
cmake                        editors                       protobuf.bzl         util
compile                      examples                      protobuf_deps.bzl    WORKSPACE
compiler_config_setting.bzl  generate_descriptor_proto.sh  protobuf-lite.pc.in
config.guess                 install-sh                    protobuf.pc.in
config.h.in                  LICENSE                       python
[mythcat@desk protobuf-3.9.2]$ ./configure
...
checking how to run the C preprocessor... gcc -E
checking how to run the C++ preprocessor... /lib/cpp
configure: error: in `/home/mythcat/protobuf-3.9.2':
configure: error: C++ preprocessor "/lib/cpp" fails sanity check
See `config.log' for more details
...
[root@desk protobuf-3.9.2]# dnf install g++
...
Installed:
  gcc-c++-9.2.1-1.fc30.x86_64                                                                               

Complete![root@desk protobuf-3.9.2]# exit
exit
Let's build again:
[mythcat@desk protobuf-3.9.2]$ ./configure
checking whether to enable maintainer-specific portions of Makefiles... yes
checking build system type... x86_64-pc-linux-gnu
...
checking that generated files are newer than configure... done
configure: creating ./config.status
config.status: creating Makefile
config.status: creating scripts/gmock-config
config.status: creating build-aux/config.h
config.status: executing depfiles commands
config.status: executing libtool commands
[mythcat@desk protobuf-3.9.2]$ nproc --all
2
[mythcat@desk protobuf-3.9.2]$ make -j2
...
  CXXLD    protoc
make[2]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
make[1]: Leaving directory '/home/mythcat/protobuf-3.9.2'
[mythcat@desk protobuf-3.9.2]$ make check -j2
...PASS: protobuf-lazy-descriptor-test
PASS: protobuf-lite-test
PASS: google/protobuf/compiler/zip_output_unittest.sh
PASS: google/protobuf/io/gzip_stream_unittest.sh
PASS: protobuf-lite-arena-test
PASS: no-warning-test
PASS: protobuf-test
============================================================================
Testsuite summary for Protocol Buffers 3.9.2
============================================================================
# TOTAL: 7
# PASS:  7
# SKIP:  0
# XFAIL: 0
# FAIL:  0
# XPASS: 0
# ERROR: 0
============================================================================
make[3]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
make[2]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
make[1]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
The last steps is for install:
[mythcat@desk protobuf-3.9.2]$ sudo make install
[sudo] password for mythcat: 
...
make[2]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
make[1]: Leaving directory '/home/mythcat/protobuf-3.9.2/src'
[mythcat@desk protobuf-3.9.2]$ sudo ldconfig 
Let's test it:
[mythcat@desk protobuf-3.9.2]$ protoc --version
libprotoc 3.9.2
Now the next step comes for python module:
[mythcat@desk protobuf-3.9.2]$ cd python/
[mythcat@desk python]$ ls
google  MANIFEST.in  mox.py  README.md  release  release.sh  setup.cfg  setup.py  stubout.py  tox.ini
[mythcat@desk python]$ python setup.py build
...
testSerialize (google.protobuf.internal.unknown_fields_test.UnknownFieldsTest) ... ok
testSerializeMessageSetWireFormatUnknownExtension 
(google.protobuf.internal.unknown_fields_test.UnknownFieldsTest) ... ok
testSerializeProto3 (google.protobuf.internal.unknown_fields_test.UnknownFieldsTest) ... ok
testByteSizeFunctions (google.protobuf.internal.wire_format_test.WireFormatTest) ... ok
testPackTag (google.protobuf.internal.wire_format_test.WireFormatTest) ... ok
testUnpackTag (google.protobuf.internal.wire_format_test.WireFormatTest) ... ok
testZigZagDecode (google.protobuf.internal.wire_format_test.WireFormatTest) ... ok
testZigZagEncode (google.protobuf.internal.wire_format_test.WireFormatTest) ... ok

----------------------------------------------------------------------
Ran 818 tests in 5.343s

OK (skipped=10)
Let's test the python module:
[mythcat@desk python]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import google
>>> from google.protobuf import descriptor as _descriptor
>>> from google.protobuf import message as _message
>>> from google.protobuf import reflection as _reflection
>>> from google.protobuf import symbol_database as _symbol_database
>>> from google.protobuf import descriptor_pb2
>>> from google.protobuf import text_format
>>> dir(_descriptor)
['Descriptor', 'DescriptorBase', 'DescriptorMetaclass', 'EnumDescriptor', 'EnumValueDescriptor', 
'Error', 'FieldDescriptor', 'FileDescriptor', 'MakeDescriptor', 'MethodDescriptor', 'OneofDescriptor', 
'ServiceDescriptor', 'TypeTransformationError', '_Lock', '_NestedDescriptorBase', '_OptionsOrNone', 
'_ParseOptions', '_ToCamelCase', '_ToJsonName', '_USE_C_DESCRIPTORS', '__author__', '__builtins__', 
'__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_lock', 
'api_implementation', 'six', 'threading']
Now I can to define the structure for the data structured as messages
These message is a small logical record of information containing a series of name-value pairs called fields.
The protobuffers compiler (protoc) to generate the source code in the language you need (from the .proto file).
To generate a Python file, you need to execute:
protoc -I=$SRC_DIR --python_out=$DST_DIR $SRC_DIR/my_example.proto
Let's test with am example (you can use any proto file) in default folder (use . for default folder):
[mythcat@desk python]$ protoc -I=. --python_out=. my_example.proto
[mythcat@desk python]$ ls my_example*
my_example_pb2.py  my_example.proto
[mythcat@desk python]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import my_example_pb2
>>> dir(my_example_pb2)
['AddressBook', 'DESCRIPTOR', 'Person', '_ADDRESSBOOK', '_PERSON', '_PERSON_PHONENUMBER', '_PERSON_PHONETYPE',
 '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__',
 '_b', '_descriptor', '_message', '_reflection', '_sym_db', '_symbol_database', 'sys']

Saturday, September 28, 2019

The tensorflow python module - part 004.

If you using the tensorflow then you can get some warnings.
You can use warnings python package to manage all of this:
[mythcat@desk ~]$ $ python3
Python 3.5.2 (default, Jul 10 2019, 11:58:48)
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import warnings
>>> import tensorflow as tf
/home/mythcat/.local/lib/python3.5/site-packages/tensorflow/python/framework/dtypes.py:516: FutureWarning: 
Passing (type, 1) or '1type' as a synonym of type is deprecated; in a future version of numpy, it will be 
understood as (type, (1,)) / '(1,)type'.
  _np_qint8 = np.dtype([("qint8", np.int8, 1)])
/home/mythcat/.local/lib/python3.5/site-packages/tensorflow/python/framework/dtypes.py:517: FutureWarning: 
Passing (type, 1) or '1type' as a synonym of type is deprecated; in a future version of numpy, it will be 
understood as (type, (1,)) / '(1,)type'.
...

/home/mythcat/.local/lib/python3.5/site-packages/tensorboard/compat/tensorflow_stub/dtypes.py:550: 
FutureWarning: Passing (type, 1) or '1type' as a synonym of type is deprecated; in a future version of 
numpy, it will be understood as (type, (1,)) / '(1,)type'.
  np_resource = np.dtype([("resource", np.ubyte, 1)])
>>>
>>> warnings.filterwarnings('ignore')
>>>
[7]+  Stopped                 python3
Use it in this way to filter these warnings:
[mythcat@desk ~]$ $ python3
Python 3.5.2 (default, Jul 10 2019, 11:58:48)
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import warnings
>>> warnings.filterwarnings('ignore',category=FutureWarning)
>>> import tensorflow as tf
>>> 

Wednesday, September 25, 2019

Python 3.7.4 : Print with random colors.

This is a simple example for custom print output.
The script detect the platform for color settings and then use print.
The first print will print with blue color the name of the script.
I used random to select a random color from colors array and used to print the -=RANDOM COLOR=- text.
The print (W+'') is used to set default white color for terminal
import sys
import random
if sys.platform == "linux" or sys.platform == "linux2":
        BB = "\033[34;1m" # Blue light
        YY = "\033[33;1m" # Yellow light
        GG = "\033[32;1m" # Green light
        WW = "\033[0;1m"  # White light
        RR = "\033[31;1m" # Red light
        CC = "\033[36;1m" # Cyan light
        B = "\033[34m"    # Blue
        Y = "\033[33m"    # Yellow
        G = "\033[32m"    # Green
        W = "\033[0m"     # White
        R = "\033[31m"    # Red
        C = "\033[36m"    # Cyan
colors = [BB,YY,GG,WW,RR,CC,B,Y,G,W,R,C]
print (B+"\033[2;2m "+sys.argv[0]+"\n"+B)

color=random.choice(colors)
print (color+"-=RANDOM COLOR=-"+color)
print (W+'')
For winodws platform you need to add this:
elif sys.platform == "win32":

 BB = '' # Blue light
 YY = '' # Yellow light
 GG = '' # Green light
 WW = '' # White light
 RR = '' # Red light
 CC = '' # Cyan light
 B = ''  # Blue
 Y = ''  # Yellow
 G = ''  # Green
 W = ''  # White
 R = ''  # Red
 C = ''  # Cyan
 P = ''  # Random color

Wednesday, September 11, 2019

Python 3.7.4 : Using the theano pakage.

If you want to test theano then you need to see this webpage.
[root@desk mythcat]# dnf search theano
======================== Name & Summary Matched: theano ========================
python-theano-doc.noarch : Theano documentation
============================= Name Matched: theano =============================
python3-theano.noarch : Mathematical expressions involving multidimensional
                      : arrays
=========================== Summary Matched: theano ============================
python3-lasagne.noarch : Lightweight library to build and train neural networks
                       : in Theano
[root@desk mythcat]# pip3 install Theano --user
WARNING: Running pip install with root privileges is generally not a good idea. 
Try `pip3 install --user` instead.
Collecting Theano
...
  Running setup.py install for Theano ... done
Successfully installed Theano-1.0.4 scipy-1.3.1
Let's see first example:
[mythcat@desk ~]$ python3 
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import theano
/home/mythcat/.local/lib/python3.7/site-packages/theano/configdefaults.py:560: 
UserWarning: DeprecationWarning: there is no c++ compiler.This is deprecated and with 
Theano 0.11 a c++ compiler will be mandatory
  warnings.warn("DeprecationWarning: there is no c++ compiler."
WARNING (theano.configdefaults): g++ not detected ! Theano will be unable to execute 
optimized C-implementations (for both CPU and GPU) and will default to Python implementations.
 Performance will be severely degraded. To remove this warning, set Theano flags cxx to an empty
 string.
WARNING (theano.tensor.blas): Using NumPy C-API based implementation for BLAS functions.
>>> import theano
>>> import theano.tensor as T
>>> x = T.dmatrix('x')
>>> s = 1 / (1 + T.exp(-x))
>>> logistic = theano.function([x], s)
>>> logistic([[0, 1], [-1, -2]])
array([[0.5       , 0.73105858],
       [0.26894142, 0.11920292]])
>>> ... 

Monday, September 9, 2019

Python 3.7.4 : Using the sunpy - part 001.

I wrote about sunpy in the past on this website.
Now this package comes with new features, see the official webpage.
Let's install it.
[mythcat@desk ~]$ pip3 install sunpy --user
Collecting sunpy
...
Successfully installed aioftp-0.13.0 aiohttp-3.6.0 astropy-3.2.1 async-timeout-3.0.1 
multidict-4.5.2 parfive-1.0.0 scipy-1.3.1 sunpy-1.0.3 tqdm-4.35.0 yarl-1.3.0
If you search on web you can find example with spectra , but in the new package is not supported.
ModuleNotFoundError: No module named 'sunpy.spectra'
Let's test it:
[mythcat@desk ~]$ python3 
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import sunpy
>>> dir(sunpy)
['SunPyTestRunner', 'UnsupportedPythonError', '__all__', '__builtins__', '__cached__', '__doc__',
 '__file__', '__loader__', '__minimum_python_version__', '__name__', '__package__', '__path__',
 '__spec__', '__version__', '_init_log', 'builtins', 'config', 'extern', 'load_config', 'log',
 'logging', 'os', 'print_config', 'self_test', 'sys', 'system_info', 'tests', 'util', 'version']
>>> sunpy.system_info()
==============================
SunPy Installation Information
==============================

#######
General
#######
Time : Monday, 09. September 2019 07:14PM UT
System : Linux
Processor : x86_64
Arch : 64bit
SunPy : 1.0.3
OS: Fedora 30 Thirty (Linux 5.2.11-200.fc30.x86_64 x86_64)


##################
Required Libraries
##################
Python: 3.7.4
NumPy: 1.16.4
SciPy: 1.3.1
matplotlib: 3.0.3
Astropy: 3.2.1
Pandas: 0.25.1
parfive: 1.0.0


#####################
Recommended Libraries
#####################
beautifulsoup: NOT INSTALLED
PyQt4: NOT INSTALLED
PyQt5: 5.12.2
Zeep: NOT INSTALLED
Sqlalchemy: 1.3.7
drms: NOT INSTALLED
>>> help(sunpy)

Help on package sunpy:

NAME
    sunpy

DESCRIPTION
    SunPy
    =====
    
    An open-source Python library for Solar Physics data analysis.
    
    Web Links
    ---------
    Homepage: https://sunpy.org
    Documentation: https://docs.sunpy.org/en/stable/

PACKAGE CONTENTS
    cm (package)
    compiler_version
    conftest
    coordinates (package)
    data (package)
    database (package)
    extern (package)
    image (package)
    instr (package)
    io (package)
    map (package)
    net (package)
    physics (package)
    roi (package)
    sun (package)
    tests (package)
    time (package)
    timeseries (package)
    util (package)
    version
    visualization (package)
... 
Let's install zeep, beautifulsoup4 and drms python packages:
[mythcat@desk ~]$ pip3 install zeep --user
Collecting zeep
...
Successfully installed appdirs-1.4.3 cached-property-1.5.1 isodate-0.6.0 lxml-4.4.1
 requests-toolbelt-0.9.1 zeep-3.4.0
[mythcat@desk ~]$ pip3 install --upgrade beautifulsoup4 --user
Collecting beautifulsoup4
...
Successfully installed beautifulsoup4-4.8.0 soupsieve-1.9.3
[mythcat@desk ~]$ pip3 install --upgrade drms --user
Collecting drms
...
Successfully installed drms-0.5.7
Now, we can see examples with this python package.
First, I will use the AIA_171_IMAGE image:
>>> from sunpy.data.sample import AIA_171_IMAGE 
Files Downloaded: 100%|███████████████████████| 26/26 [00:04<00:00 5.50file="" s="">>> import sunpy.map                                                            
>>> aiamap = sunpy.map.Map(AIA_171_IMAGE)
>>> aiamap.peek()                                                               
Attribute Qt::AA_EnableHighDpiScaling must be set before QCoreApplication is created.                                                                           

** (python3:4152): WARNING **: 22:53:15.329: AT-SPI: Could not obtain desktop path or name


** (python3:4152): WARNING **: 22:53:15.377: atk-bridge: GetRegisteredEvents returned message with unknown signature



Python 3.7.3 : Using the flask - part 018.

In this tutorial, I will show you how to fix auto increment in Flask SQLAlchemy.
The old source code for the user model from the server.py was this:
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    password = db.Column(db.String(120), unique=True)
    email = db.Column(db.String(120), unique=True)
    gender = db.Column(db.String(5), unique=True)
    work = db.Column(db.String(33), unique=True)
    city = db.Column(db.String(15), unique=True)
The server.sqlite will be this:
[mythcat@desk my_flask]$ sqlite3 server.sqlite 
SQLite version 3.26.0 2018-12-01 12:34:55
Enter ".help" for usage hints.
sqlite> .schema
CREATE TABLE user (
 id INTEGER NOT NULL, 
 username VARCHAR(80), 
 password VARCHAR(120), 
 email VARCHAR(120), 
 gender VARCHAR(5), 
 work VARCHAR(33), 
 city VARCHAR(15), 
 PRIMARY KEY (id), 
 UNIQUE (username), 
 UNIQUE (password), 
 UNIQUE (email), 
 UNIQUE (gender), 
 UNIQUE (work), 
 UNIQUE (city)
);
CREATE TABLE alembic_version (
 version_num VARCHAR(32) NOT NULL, 
 CONSTRAINT alembic_version_pkc PRIMARY KEY (version_num)
);
CREATE TABLE sqlite_stat1(tbl,idx,stat);
sqlite> ^Z 
If you want to change the id into auto increment then you need to follow this steps:
class User(db.Model):
    __tablename__ = 'user'
    __table_args__ = {'sqlite_autoincrement': True}
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    password = db.Column(db.String(120), unique=True)
    email = db.Column(db.String(120), unique=True)
    gender = db.Column(db.String(5), unique=True)
    work = db.Column(db.String(33), unique=True)
    city = db.Column(db.String(15), unique=True)
Delete the server.sqlite file or rename it.
Open python3 and create a new server.sqlite file:
[mythcat@desk my_flask]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
>>> db.create_all()
>>> db.engine.table_names()
['sqlite_sequence', 'user']
>>> 
[5]+  Stopat                  python3 
Open the new file to see the changes:
[mythcat@desk my_flask]$ sqlite3 server.sqlite 
SQLite version 3.26.0 2018-12-01 12:34:55
Enter ".help" for usage hints.
sqlite> .schema
CREATE TABLE user (
 id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, 
 username VARCHAR(80), 
 password VARCHAR(120), 
 email VARCHAR(120), 
 gender VARCHAR(5), 
 work VARCHAR(33), 
 city VARCHAR(15), 
 UNIQUE (username), 
 UNIQUE (password), 
 UNIQUE (email), 
 UNIQUE (gender), 
 UNIQUE (work), 
 UNIQUE (city)
);
CREATE TABLE sqlite_sequence(name,seq);
sqlite>  

Wednesday, September 4, 2019

Python 3.7.4 : Create an Stand Alone Executable on Fedora distro.

In this tutorial I will show you how to create an Stand Alone Executable with Python version 3.7.4 and Fedora 30 distro.
First you need to install using the dnf tool the python3 package.
You can test it easy with this command:
[mythcat@desk dist]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information. 
I created a simple python script named test.py for testing:
import os
import sys
print("Hello!")
You need to install the pyinstaller python module.
Let's see this step with the output:
[mythcat@desk ~]$ pip3 install pyinstaller --user
Now you can use this python module to create Stand Alone Executable.
[mythcat@desk ~]$ pip3 install pyinstaller --user
Requirement already satisfied: pyinstaller in ./.local/lib/python3.7/site-packages (3.5)
Requirement already satisfied: setuptools in /usr/lib/python3.7/site-packages (from pyinstaller) (40.8.0)
Requirement already satisfied: altgraph in ./.local/lib/python3.7/site-packages (from pyinstaller) (0.16.1)
[mythcat@desk ~]$ pyinstaller --onefile test.py
561 INFO: PyInstaller: 3.5
561 INFO: Python: 3.7.4
571 INFO: Platform: Linux-5.2.9-200.fc30.x86_64-x86_64-with-fedora-30-Thirty
573 INFO: wrote /home/mythcat/test.spec
596 INFO: UPX is not available.
598 INFO: Extending PYTHONPATH with paths
['/home/mythcat', '/home/mythcat']
598 INFO: checking Analysis
624 INFO: Building because /home/mythcat/test.py changed
624 INFO: Initializing module dependency graph...
640 INFO: Initializing module graph hooks...
678 INFO: Analyzing base_library.zip ...
5247 INFO: running Analysis Analysis-00.toc
5352 INFO: Caching module hooks...
5376 INFO: Analyzing /home/mythcat/test.py
5396 INFO: Loading module hooks...
5397 INFO: Loading module hook "hook-xml.py"...
5775 INFO: Loading module hook "hook-pydoc.py"...
5800 INFO: Loading module hook "hook-encodings.py"...
5892 INFO: Looking for ctypes DLLs
5893 INFO: Analyzing run-time hooks ...
5901 INFO: Looking for dynamic libraries
6507 INFO: Looking for eggs
6507 INFO: Using Python library /lib64/libpython3.7m.so.1.0
6514 INFO: Warnings written to /home/mythcat/build/test/warn-test.txt
6547 INFO: Graph cross-reference written to /home/mythcat/build/test/xref-test.html
6604 INFO: checking PYZ
6607 INFO: Building because toc changed
6607 INFO: Building PYZ (ZlibArchive) /home/mythcat/build/test/PYZ-00.pyz
7030 INFO: Building PYZ (ZlibArchive) /home/mythcat/build/test/PYZ-00.pyz completed successfully.
7034 INFO: checking PKG
7035 INFO: Building because toc changed
7035 INFO: Building PKG (CArchive) PKG-00.pkg
10033 INFO: Building PKG (CArchive) PKG-00.pkg completed successfully.
10036 INFO: Bootloader 
/home/mythcat/.local/lib/python3.7/site-packages/PyInstaller/bootloader/Linux-64bit/run
10036 INFO: checking EXE
10123 INFO: Building because toc changed
10124 INFO: Building EXE from EXE-00.toc
10163 INFO: Appending archive to ELF section in EXE /home/mythcat/dist/test
10337 INFO: Building EXE from EXE-00.toc completed successfully.
This command will create some folders: dist, build, ...
The dist folder will have the Stand Alone Executable named test:
[mythcat@desk ~]$ cd dist/
[mythcat@desk dist]$ ls
test
[mythcat@desk dist]$ ./test
Hello!

Tuesday, August 27, 2019

Python 3.7.3 : Using the flask - part 017.

Today I make some changes with my server.py and database and solve some issues, see old version at my old tutorial.
Firt issue was start script.
I create a linux script named start_server.sh to run the flask run command:
[mythcat@desk my_flask]$ ./start_server.sh 
I update the User with new fiels:
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    password = db.Column(db.String(120), unique=True)
    email = db.Column(db.String(120), unique=True)
    gender = db.Column(db.String(5), unique=True)
    work = db.Column(db.String(33), unique=True)
    city = db.Column(db.String(15), unique=True)
Let's see how I deal with this versus database and migrate process.
[mythcat@desk my_flask]$ rm server.sqlite 
[mythcat@desk my_flask]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
>>> db.create_all()
>>> db.engine.table_names()
['user']
>>> exit()
[mythcat@desk my_flask]$ ls server.sqlite 
server.sqlite
[mythcat@desk my_flask]$ sqlite3 server.sqlite 
SQLite version 3.26.0 2018-12-01 12:34:55
Enter ".help" for usage hints.
sqlite> .tables
user
sqlite> .schema user
CREATE TABLE user (
        id INTEGER NOT NULL, 
        username VARCHAR(80), 
        password VARCHAR(120), 
        email VARCHAR(120), 
        gender VARCHAR(5), 
        work VARCHAR(33), 
        city VARCHAR(15), 
        PRIMARY KEY (id), 
        UNIQUE (username), 
        UNIQUE (password), 
        UNIQUE (email), 
        UNIQUE (gender), 
        UNIQUE (work), 
        UNIQUE (city)
);
I got a strange error:
sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) duplicate column name: city
I fix it with this , but I'm not sure if the right way:
[mythcat@desk my_flask]$ rm migrations/ -r -f 
[mythcat@desk my_flask]$ python3 server.py db init 
  Creating directory /home/mythcat/project_github/my_flask/migrations ... done
  Creating directory /home/mythcat/project_github/my_flask/migrations/versions ... done
  Generating /home/mythcat/project_github/my_flask/migrations/script.py.mako ... done
  Generating /home/mythcat/project_github/my_flask/migrations/env.py ... done
  Generating /home/mythcat/project_github/my_flask/migrations/alembic.ini ... done
  Generating /home/mythcat/project_github/my_flask/migrations/README ... done
  Please edit configuration/connection/logging settings in '/home/mythcat/project_github/my_flask/migrations/alembic.ini'
  before proceeding.
[mythcat@desk my_flask]$ python3 server.py db migrate
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.env] No changes in schema detected.
[mythcat@desk my_flask]$ python3 server.py db upgrade
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.

Sunday, August 25, 2019

Python 3.7.3 : Using the flask - part 016.

Today I tested a new feature of Flask version 1.1.1.
[mythcat@desk my_flask]$ pip list | grep Flask
Flask                    1.1.1            
Flask-Login              0.4.1            
Flask-Mail               0.9.1            
Flask-Migrate            2.5.2            
Flask-Script             2.0.6            
Flask-SQLAlchemy         2.4.0            
Flask-WTF                0.14.2 
This feature will remove the jsonify python module.
Let's start the blueprint blue_test:
[mythcat@desk my_flask]$ export FLASK_APP=blue_test
[mythcat@desk my_flask]$ flask run 
 * Serving Flask app "blue_test"
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
The output is this:
 {"result":"This is main page!"}
Into my blue_test folder I will remove this jsonify python module:
[
mythcat@desk my_flask]$ cd blue_test/
[mythcat@desk blue_test]$ ll
total 40
-rw-rw-r--. 1 mythcat mythcat  192 Aug 23 11:02 extensions.py
-rw-rw-r--. 1 mythcat mythcat 1826 Aug 23 11:02 forms.py
-rw-rw-r--. 1 mythcat mythcat  701 Aug 23 12:03 __init__.py
-rw-rw-r--. 1 mythcat mythcat 1491 Aug 23 11:02 models.py
drwxrwxr-x. 2 mythcat mythcat  184 Aug 25 14:36 __pycache__
-rw-rw-r--. 1 mythcat mythcat 1050 Aug 23 11:02 routes.py
-rw-rw-r--. 1 mythcat mythcat  142 Aug 23 11:02 settings.py
-rw-rw-r--. 1 mythcat mythcat   34 Aug 23 11:02 start.bat
drwxrwxr-x. 2 mythcat mythcat   81 Aug 23 11:02 templates
-rw-rw-r--. 1 mythcat mythcat 8192 Aug 23 11:02 texts.sqlite
-rw-rw-r--. 1 mythcat mythcat  677 Aug 23 11:02 views.py 
The routes.py will have these changes:
#from flask import Blueprint, jsonify, request
# new flask
from flask import Blueprint, request
...
def home():
    #return jsonify({'result' : 'This is main page!'})
    #this is the new source code:
    return {'result' : 'This is main page!'} 
The next step is to find all jsonify word into my source code using the grep tool and make changes:
[mythcat@desk my_flask]$ grep -nr jsonify *
Binary file blue_test/__pycache__/views.cpython-37.pyc matches
blue_test/views.py:3:from flask import Blueprint, jsonify, request
blue_test/views.py:20:    return jsonify ({'texts':texts})
blue_test/routes.py:1:#from flask import Blueprint, jsonify, request
crud.py:1:from flask import Flask, request, jsonify
crud.py:57:    return jsonify(new_user)
crud.py:64:    return jsonify(result.data)
crud.py:70:    return user_schema.jsonify(user)
crud.py:83:    return user_schema.jsonify(user)
crud.py:92:    return user_schema.jsonify(user)
Binary file __pycache__/crud.cpython-37.pyc matches
Binary file __pycache__/server.cpython-37.pyc matches
server.py:9:from flask import jsonify
server.py:101:    #return jsonify(new_user)
server.py:109:    #return users_schema.jsonify(users)
server.py:111:    return jsonify(all_users.data)
server.py:117:    return jsonify(result.data)
server.py:122:        return jsonify([d['keyword'] for d in result.data])
server.py:132:    return user_schema.jsonify(new_user)
tserv.py:13:from flask import jsonify
tserv.py:56:    #return users_schema.jsonify(users)
tserv.py:58:    return jsonify(all_users.data)
tserv.py:69:    return user_schema.jsonify(user_post)
tserv.py:80:    return user_schema.jsonify(user_put)
tserv.py:88:    return user_schema.jsonify(user_delete)
[mythcat@desk my_flask]$  
After I make changes the result of grep is this:
[mythcat@desk my_flask]$ grep -nr jsonify *
Binary file blue_test/__pycache__/views.cpython-37.pyc matches
blue_test/routes.py:1:#from flask import Blueprint, jsonify, request
blue_test/views.py:3:#from flask import Blueprint, jsonify, request
crud.py:1:#from flask import Flask, request, jsonify
Binary file __pycache__/crud.cpython-37.pyc matches
Binary file __pycache__/server.cpython-37.pyc matches
server.py:9:#from flask import jsonify
server.py:109:    #return users_schema.jsonify(users)
tserv.py:13:#from flask import jsonify
tserv.py:56:    #return users_schema.jsonify(users) 
You can see the last version of my project here.







Saturday, August 24, 2019

Python 3.7.3 : Using the flask - part 015.

In this tutorial, I will show you how to migrate using the Database Migrations in flask project.
Because my laptop is gone I use my old Linux.
First you need to install these python modules with --user argument for Linux:
[mythcat@desk my_flask]$ pip3 install flask-migrate --user
...
[mythcat@desk my_flask]$ pip3 install flask-script --user
Let's test this new issue with server.py file by adding these python modules:
#migrate 
from flask_script import Manager
from flask_migrate import Migrate, MigrateCommand
...
# create migrate object with db 
migrate = Migrate(app, db)
# create manager 
manager = Manager(app)
# create db command for manager 
manager.add_command('db', MigrateCommand)
...
# add new columns into database 
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)
    gender = db.Column(db.String(5), unique=True)
    work = db.Column(db.String(33), unique=True)
    city = db.Column(db.String(15), unique=True)
...
# the default name main
if __name__ == '__main__':
    manager.run()
    app.run(debug=True)
Let's fix this migrate issue with the new command:
[mythcat@desk my_flask]$ python3 server.py db init 
  Creating directory /home/mythcat/project_github/my_flask/migrations ... done
  Creating directory /home/mythcat/project_github/my_flask/migrations/versions ... done
  Generating /home/mythcat/project_github/my_flask/migrations/script.py.mako ... done
  Generating /home/mythcat/project_github/my_flask/migrations/env.py ... done
  Generating /home/mythcat/project_github/my_flask/migrations/alembic.ini ... done
  Generating /home/mythcat/project_github/my_flask/migrations/README ... done
  Please edit configuration/connection/logging settings in '/home/mythcat/project_github/my_flask/migrations
/alembic.ini'
  before proceeding.

[mythcat@desk my_flask]$ python3 server.py db migrate
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.autogenerate.compare] Detected added column 'user.city'
INFO  [alembic.autogenerate.compare] Detected added column 'user.gender'
INFO  [alembic.autogenerate.compare] Detected added column 'user.work'
INFO  [alembic.autogenerate.compare] Detected added unique constraint 'None' on '['city']'
INFO  [alembic.autogenerate.compare] Detected added unique constraint 'None' on '['gender']'
INFO  [alembic.autogenerate.compare] Detected added unique constraint 'None' on '['work']'
  Generating /home/mythcat/project_github/my_flask/migrations/versions/ca70c42b5b7a_.py ... done

[mythcat@desk my_flask]$ python3 server.py db upgrade 
INFO  [alembic.runtime.migration] Context impl SQLiteImpl.
INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
INFO  [alembic.runtime.migration] Running upgrade  -> ca70c42b5b7a, empty message
ERROR [root] Error: No support for ALTER of constraints in SQLite dialect
The database fiels is changed by this command.
Let's see with sqlite3 tool:
[mythcat@desk my_flask]$ sqlite3 server.sqlite 
SQLite version 3.26.0 2018-12-01 12:34:55
Enter ".help" for usage hints.
sqlite> .tables
alembic_version  user           
sqlite> .schema user
CREATE TABLE user (
        id INTEGER NOT NULL, 
        username VARCHAR(80), 
        email VARCHAR(120), city VARCHAR(15), gender VARCHAR(5), work VARCHAR(33), 
        PRIMARY KEY (id), 
        UNIQUE (username), 
        UNIQUE (email)
);
You can see my source code here.

Thursday, August 22, 2019

Python 3.7.3 : Using the inotify.

About this tool you can read here:
inotify functionality is available from the Linux kernel and allows you to register one or more directories for watching, and to simply block and wait for notification events.
[mythcat@desk ~]$ pip3 install inotify --user
...
Successfully installed inotify-0.2.10 nose-1.3.7
Let's test it and see how this can be load it:
[mythcat@desk ~]$ python3
Python 3.7.4 (default, Jul  9 2019, 16:32:37) 
[GCC 9.1.1 20190503 (Red Hat 9.1.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import inotify
>>> from inotify import *
>>> print(dir(inotify))
['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', 
'__path__', '__spec__', '__version__']
>>> import inotify.adapters
>>> print(dir(inotify))
['__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', 
'__path__', '__spec__', '__version__', 'adapters', 'calls', 'constants', 'library']
>>> print(dir(inotify.adapters))
['EINTR', 'EventTimeoutException', 'Inotify', 'InotifyTree', 'InotifyTrees', 'TerminalEventException', 
'_BaseTree', '_DEFAULT_EPOLL_BLOCK_DURATION_S', '_DEFAULT_TERMINAL_EVENTS', '_HEADER_STRUCT_FORMAT', 
'_INOTIFY_EVENT', '_IS_DEBUG', '_LOGGER', '_STRUCT_HEADER_LENGTH', '__builtins__', '__cached__', '__doc__',
 '__file__', '__loader__', '__name__', '__package__', '__spec__', 'collections', 'inotify', 'logging', 'os',
 'select', 'struct', 'time']
>>> import inotify.calls
>>> print(dir(inotify.calls))
['InotifyError', '_LIB', '_LOGGER', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', 
'__name__', '__package__', '__spec__', '_check_nonnegative', '_check_nonzero', '_check_zero', 'ctypes', 
'errno', 'inotify', 'inotify_add_watch', 'inotify_init', 'inotify_rm_watch', 'logging']
>>> import inotify.constants
>>> print(dir(inotify.constants))
['IN_ACCESS', 'IN_ALL_EVENTS', 'IN_ATTRIB', 'IN_CLOEXEC', 'IN_CLOSE', 'IN_CLOSE_NOWRITE', 'IN_CLOSE_WRITE', 
'IN_CREATE', 'IN_DELETE', 'IN_DELETE_SELF', 'IN_DONT_FOLLOW', 'IN_IGNORED', 'IN_ISDIR', 'IN_MASK_ADD', 
'IN_MODIFY', 'IN_MOVE', 'IN_MOVED_FROM', 'IN_MOVED_TO', 'IN_MOVE_SELF', 'IN_NONBLOCK', 'IN_ONESHOT', 
'IN_ONLYDIR', 'IN_OPEN', 'IN_Q_OVERFLOW', 'IN_UNMOUNT', 'MASK_LOOKUP', '__builtins__', '__cached__', 
'__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__']
>>> import inotify.library
>>> print(dir(inotify.library))
['_FILEPATH', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', 
'__spec__',
 'ctypes', 'instance']
Let's test it with a simple watch issue for a file named test_file.
First, let create this file:
[mythcat@desk ~]$ touch /tmp/test_file
[mythcat@desk ~]$ ll /tmp/test_file 
-rw-rw-r--. 1 mythcat mythcat 0 Aug 22 13:54 /tmp/test_file
Now, I can use the next script to watch on it:
import inotify.adapters
def notif_tmp():
    adapter_tmp = inotify.adapters.Inotify()

    adapter_tmp.add_watch('/tmp')

    with open('/tmp/test_file', 'w'):
        pass

    events = adapter_tmp.event_gen(yield_nones=False, timeout_s=1)
    events = list(events)

    print(events)
if __name__ == '__main__':
    notif_tmp()
The result is this:
$ python3 notif.py 
[(_INOTIFY_EVENT(wd=1, mask=2, cookie=0, len=16), ['IN_MODIFY'], '/tmp', 'test_file'), 
(_INOTIFY_EVENT(wd=1, mask=32, cookie=0, len=16), ['IN_OPEN'], '/tmp', 'test_file'), 
(_INOTIFY_EVENT(wd=1, mask=8, cookie=0, len=16), ['IN_CLOSE_WRITE'], '/tmp', 'test_file')]
If remove this file the result will be this:
$ python3 notif.py 
[(_INOTIFY_EVENT(wd=1, mask=256, cookie=0, len=16), ['IN_CREATE'], '/tmp', 'test_file'), 
(_INOTIFY_EVENT(wd=1, mask=32, cookie=0, len=16), ['IN_OPEN'], '/tmp', 'test_file'), 
(_INOTIFY_EVENT(wd=1, mask=8, cookie=0, len=16), ['IN_CLOSE_WRITE'], '/tmp', 'test_file')]
Let's test another example:
import inotify.adapters
import logging
_LOGGER = logging.getLogger(__name__)
def test():
    i = inotify.adapters.Inotify()
    i.add_watch('/tmp')

    try:
        for event in i.event_gen():
            if event is not None:
                (header, type_names, path, filename) = event
                _LOGGER.info("WD=(%d) MASK=(%d) COOKIE=(%d) LEN=(%d) MASK->NAMES=%s "
                             "FILENAME=[%s]",
                             header.wd, header.mask, header.cookie, header.len, type_names,
                             filename)
                print(header, type_names, path, filename)
    finally:
        i.remove_watch('/tmp')

if __name__ == '__main__':
    test()
If you run this and will try to edit with vim editor the /tmp/text.txt file the output will be this:
$ python3 notif_002.py
_INOTIFY_EVENT(wd=1, mask=32, cookie=0, len=16) ['IN_OPEN'] /tmp text.txt
_INOTIFY_EVENT(wd=1, mask=256, cookie=0, len=16) ['IN_CREATE'] /tmp .text.txt.swp
_INOTIFY_EVENT(wd=1, mask=32, cookie=0, len=16) ['IN_OPEN'] /tmp .text.txt.swp
...
If you want to use many paths then use this:
    paths = [
        '/tmp',
    ]
    i = Inotify(paths=paths)
This module is not well documented but can be successfully used for certain tasks.

Wednesday, August 21, 2019

Python Qt5 : contextMenu example.

A context menu is a menu in a graphical user interface (GUI) that appears upon user interaction, such as a right-click mouse operation.
I create the default application and I use QMenu to create this context menu with New, Open and Quit.
from PyQt5 import QtGui
from PyQt5.QtWidgets import QApplication, QMainWindow, QMenu
import sys


class Window(QMainWindow):
    def __init__(self):
        super().__init__()
        self.title = "PyQt5 Context Menu"
        self.top = 100
        self.left = 100
        self.width = 640
        self.height = 480
        self.InitWindow()


    def InitWindow(self):
        self.setWindowIcon(QtGui.QIcon("icon.png"))
        self.setWindowTitle(self.title)
        self.setGeometry(self.left, self.top, self.width, self.height)
        self.show()

    def contextMenuEvent(self, event):
        contextMenu = QMenu(self)
        new_Act = contextMenu.addAction("New")
        open_Act = contextMenu.addAction("Open")
        quit_Act = contextMenu.addAction("Quit")
        action = contextMenu.exec_(self.mapToGlobal(event.pos()))
        if action == quit_Act:
            self.close()


App = QApplication(sys.argv)
window = Window()
sys.exit(App.exec())

Tuesday, August 20, 2019

Python Qt5 : the QTimer class.

I haven't written about PyQt5 in a while and today I decided to add a short tutorial on this python module.
The QTimer class is a high-level programming interface for timers and provides repetitive and single-shot timers.
I this example I call a method every second with these lines:
        self.timer = QTimer()
        self.timer.timeout.connect(self.handleTimer)
        self.timer.start(1000)
The timer is stop when the value check by handleTimer has value 100 else the ProgressBar increment the default value with 1.
The full source of code is this:
import sys
from PyQt5.QtCore import QTimer
from PyQt5.QtWidgets import QApplication, QMainWindow, QProgressBar
from PyQt5.QtCore import Qt

class QTimer_ProgressBar(QMainWindow):

    def __init__(self):
        super().__init__()

        self.pbar = QProgressBar(self)
        self.pbar.setGeometry(30, 70,400, 50)
        self.pbar.setValue(0)

        self.setWindowTitle("QTimer Progressbar")
        self.setGeometry(64,64,640,480)
        self.show()

        self.timer = QTimer()
        self.timer.timeout.connect(self.handleTimer)
        self.timer.start(1000)

    def handleTimer(self):
        value = self.pbar.value()
        if value < 100:
            value = value + 1
            self.pbar.setValue(value)
        else:
            self.timer.stop()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = QTimer_ProgressBar()
    sys.exit(app.exec_())
You can also use it like this:
def Qt():
    try:
        # Do things
    finally:
        QTimer.singleShot(5000, Qt)

Qt()

Wednesday, August 14, 2019

Python 3.7.3 : Using the flask - part 014.

Today I worked on YouTube search with flask and Google A.P.I. project.
The source code is simple to understand and you can test any A.P.I. from google using this way.
I created a new Google project with YouTube A.P.I. version 3 and with the A.P.I. key.
I use this key to connect with flask python module.
I used the isodate python module.
You can see the source code on my GitHub repo named flask_yt.
The result is this:

Friday, August 9, 2019

Python 3.7.3 : Using the flask - part 013.

Flask uses Jinga2 template engine.
The Jinga2 template engine uses the following delimiters for escaping from HTML.
We can use this:
  • {% ... %} for Statements
  • {{ ... }} for Expressions to print to the template output
  • {# ... #} for Comments not included in the template output
  • # ... ## for Line Statements
The documentation webpage comes with all information about how can be used.
I create a new HTML5 file named layout.html and I will use this like an example:
{% if current_user.is_authenticated %}
...
{% else %}
...
{% endif %}
This file can be add into another file like this:
{% extends "layout.html" %}
{% block content %}
...
{% endblock content %}
For example, my about.html webpage comes with this source code:
{% extends "layout.html" %}
{% block content %}
    

About Page

{% endblock content %}
The routes.py this webpage will have this call:
@app.route("/about")
def about():
    return render_template('about.html', title='About')
In this way, I will add more HTML5 files to the project.


Thursday, August 8, 2019

Python 3.7.3 : Using the flask - part 012.

The goal of this tutorial step is to understand how the project can use the new features and implementation of the project.
Because in the last tutorial I used the flask_mail python module, now I will add into my project structure.
One good issue is registration issue for users.
First, you need to see the full project and changes at my GitHub project.
I used the itsdangerous python module to use tokens.
Let's install this with the pip tool:
C:\Python373\Scripts>pip install itsdangerous
For registration is need to have login issues and we can use LoginManager, see the extensions.py
#use SQLAlchemy
from flask_sqlalchemy import SQLAlchemy
#use LoginManager
from flask_login import LoginManager
#create login_manager
login_manager = LoginManager()
#create db
db = SQLAlchemy()
Let's see the new User model, see the models.py:
#imports for user model
from datetime import datetime
from .extensions import db
from itsdangerous import TimedJSONWebSignatureSerializer as Serializer
from blue_test import login_manager
from flask_login import UserMixin

# import db from base folder, see dot
from .extensions import db 

#load the user by id
@login_manager.user_loader
def load_user(user_id):
    return User.query.get(int(user_id))

# create the Texts mode
class Texts(db.Model):
    # primary key 
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(50))
    txt_content = db.Column(db.String(1000))
    
# create the User model
'''
id = id key for user
username = name
email = user email
password = user password

'''
class User(db.Model, UserMixin):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(20), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password = db.Column(db.String(60), nullable=False)

    def get_reset_token(self, expires_sec=1800):
        s = Serializer(app.config['SECRET_KEY'], expires_sec)
        return s.dumps({'user_id': self.id}).decode('utf-8')

    @staticmethod
    def verify_reset_token(token):
        s = Serializer(app.config['SECRET_KEY'])
        try:
            user_id = s.loads(token)['user_id']
        except:
            return None
        return User.query.get(user_id)

    def __repr__(self):
        return f"User('{self.username}', '{self.email}')"
In the blue_test folder project I created the templates folder with two HTML5 files: home.html and register.html.
I created also the forms.py file and I update with my forms: RegistrationForm,RequestResetForm, ResetPasswordForm.
#import python for create forms 
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField
# import python for validate forms field
from wtforms.validators import DataRequired, Length, Email, EqualTo, ValidationError
#import python files project
from .extensions import db, login_manager

class RegistrationForm(FlaskForm):
    username = StringField('Username',
                           validators=[DataRequired(), Length(min=2, max=25)])
    email = StringField('Email',
                        validators=[DataRequired(), Email()])
    password = PasswordField('Password', validators=[DataRequired()])
    confirm_password = PasswordField('Confirm Password',
                                     validators=[DataRequired(), EqualTo('password')])
    submit = SubmitField('Sign Up')

    def validate_username(self, username):
        user = User.query.filter_by(username=username.data).first()
        if user:
            raise ValidationError('That username is taken.')

    def validate_email(self, email):
        user = User.query.filter_by(email=email.data).first()
        if user:
            raise ValidationError('That email is taken.')

class RequestResetForm(FlaskForm):
    email = StringField('Email',
                        validators=[DataRequired(), Email()])
    submit = SubmitField('Password Reset')

    def validate_email(self, email):
        #get user by email
        
        if user is None:
            raise ValidationError('There is no account with that email.')

class ResetPasswordForm(FlaskForm):
    password = PasswordField('Password', validators=[DataRequired()])
    confirm_password = PasswordField('Confirm Password',
                                     validators=[DataRequired(), EqualTo('password')])
    submit = SubmitField('Reset Password')
In the __init__.py file I add this:
#import python files project
from .extensions import db, login_manager
...
    login_manager.init_app(app)
The routers.py will have the new RegistrationForm:
@api.route("/register", methods=['GET', 'POST'])
def register():
    # check if the user is authenticated
    if current_user.is_authenticated:
        return redirect(url_for('home'))
    form = RegistrationForm()
    if form.validate_on_submit():
        flash('Your account has been created!, 'success')
        return redirect(url_for('login'))
    return render_template('register.html', title='Register', form=form)
Depending on your needs, we will send and redirect these forms to the HTML files.
Depending on your needs (users, page access, ...) we will be able to write the source code further.

Wednesday, August 7, 2019

Python 3.7.3 : Using the flask - part 011.

The tutorial for today is focused on the email issue.
I will start with the new python module for flask named flask_mail.
Let's install it:
C:\Python373>cd Scripts

C:\Python373\Scripts>pip3 install flask_mail
Collecting flask_mail
...
Installing collected packages: blinker, flask-mail
Successfully installed blinker-1.4 flask-mail-0.9.1
The next source code let show you how can use this python module.
from flask import Flask 
from flask_mail import Mail, Message

app = Flask(__name__)
app.config['DEBUG'] = True
app.config['TESTING'] = False
app.config['MAIL_SERVER'] = 'smtp...'
app.config['MAIL_PORT'] = 25
app.config['MAIL_USE_TLS'] = False
app.config['MAIL_USE_SSL'] = False
#app.config['MAIL_DEBUG'] = True # debug 
app.config['MAIL_USERNAME'] = None
app.config['MAIL_PASSWORD'] = None
# this will send with the name of another@mail.com
#app.config['MAIL_DEFALT_SENDER'] = ('Another mail', 'another@mail.com')
app.config['MAIL_DEFALT_SENDER'] = None
app.config['MAIL_MAX_EMAILS'] = None # limit the messages send
#app.config['MAIL_SUPRESS_SEND'] = False # testing
app.config['MAIL_ASCII_ATTACHMENTS'] = False

# send an email with the flask application
mail = Mail(app)

@app.route('/mail')
def mail():
    #msg = Message('Hey', sender='another@mail.com')
    #msg = Message('Hey', recipients=['catafest@yahoo.com', 'another@mail.com'])
    #msg.add_recipient = ('another@mail.com')
    msg = Message('Hey', recipients=['catafest@yahoo.com'])

    # you can use body or HTML, using both wills receive the HTML first
    #msg.body = 'This is a body text message!'
    msg.html = 'This is a body text message with HTML5 tags!'

    #add a file attachment to message 
    with app.open_resource('photo.jpg') as add_file_res:
         msg.attach('photo.jpg', 'image/jpeg', add_file_res.read())
    '''
    #create a template message 
    msg = Message(
    subject ='',
    recipients=[],
    body = '',
    html = '',
    sender = '',
    cc = [],
    bcc = [],
    attachments = [],
    reply_to = [],
    date = '',
    charset = [],
    extra_headers = {'':''},
    mail_options = [],
    rcpt_options = []
    )
    '''
    #send mail
    mail.send(msg)
    return 'Message sent!'

@app.route('/bulk')
def bulk():
    users = [{'name':'Me', 'email':'another@mail.com'}]
    # open an connection 
    with mail.connect() as con:
         for user in users:
             msg = Message('Bulk message!', recipients=[user['email']]
             msg.body = 'Body message!'
             con.send(msg)
'''
# another example 
@app.route('/bulk')
def bulk():
    users = [{'name':'Me', 'email':'another@mail.com'}]
    # open an connection 
    with mail.connect() as con:
         for user in users:
             msg = Message('Bulk message!', recipients=[user.email]
             msg.body = 'Body message!'
             con.send(msg)
'''
if __name__ == '__main__':
    app.run()
You can see you need to set the settings for your mail server and then use it into flaks application.
The source code is easy to understand if you follow the commented rows.
I add also put into comments alternative examples for the template message and the bulk function.
This is the first step into sending emails with flask.
We can have a complete implementation on the project but all depends on project structure.

Tuesday, August 6, 2019

Python 3.7.3 : Using the flask - part 010.

If you read my last tutorial about flask then you understand how to use the structure flask project with views.py and models.py.
If you run it and open the browser with http://127.0.0.1:5000/texts/ the result will be this:
{"texts":[{"title":"first title","txt_content":"this is first content"},{"title":null,"txt_content":null}]}
Let's create a file .env into the base folder named my_flask and add this source code:
SECRET_KEY='secret key'
DEBUG=True
SQLALCHEMY_TRACK_MODIFICATIONS = False
SQLALCHEMY_DATABASE_URI = sqlite:///texts.sqlite
Let's create a settings.py file into blue_test folder to get these settings:
import os
from os import environ
SECRET_KEY = os.environ.get('SECRET_KEY')
SQLALCHEMY_DATABASE_URI = os.environ.get('SQLALCHEMY_DATABASE_URI')
My blue_test project comes with the old views.py and a new routes.py file with this source code:
from flask import Blueprint, jsonify, request

api = Blueprint('api', __name__)

@api.route('/')
def home():
    return jsonify({'result' : 'You are in main page!'}) 
I create an extensions.py python script to deal with the database, see the source code:
from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()
With this new python file will solve the avoid circular importing of circular dependency of importing db.
This changes can be made on models.py and views.py, like this:
# import db from base folder, see dot
from .extensions import db 
This two files views.py and routes.py come with two Blueprint's: main and api.
Into the __init__.py will need to import and register both :
from .extensions import db
from .models import Texts
from .routes import api
from .views import main
...
    app.register_blueprint(main)
    app.register_blueprint(api)
If you run it into my_flask folder with:
C:\Python373\my_flask>set FLASK_APP=blue_test

C:\Python373\my_flask>flask run
 * Serving Flask app "blue_test"
 * Environment: production
...
The result into the browser area with http://127.0.0.1:5000/ for the routes.py blueprint api will be:
{"result":"You are in main page!"}
The result into the browser area with http://127.0.0.1:5000/texts/ for the views.py blueprint main will be:
{"texts":[{"title":"first title","txt_content":"this is first content"},{"title":null,"txt_content":null}]}
This shows you how to link multiple blueprints into one project.
You can see the full project at my GitHub project.

Monday, August 5, 2019

Python 3.7.3 : Using the flask - part 009.

In this tutorial, I will show you how to use blueprints with a new type of flask project using multiple python files.
I show you just how to create the A.P.I. not the REACT front end.
Flask uses a concept of blueprints for making application components and supporting common patterns within an application or across applications. Blueprints can greatly simplify how large applications work and provide a central means for Flask extensions to register operations on applications. A Blueprint object works similarly to a Flask application object, but it is not actually an application. Rather it is a blueprint of how to construct or extend an application., see the official webpage.
In my my_flask folder, I create a blue_test folder with three python files: __init__.py, views.py, and models.py.
The __init__.py file has this source code:
from flask import Flask
from flask_sqlalchemy import SQLAlchemy

# create path for SQLAlchemy
import os
basedir = os.path.abspath(os.path.dirname(__file__))

db = SQLAlchemy()

def create_app():
    app = Flask(__name__)
    # instantiate config for SQLAlchemy
    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
    app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'texts.sqlite')
    # init db 
    db.init_app(app)
    # avoid circular importing of circular dependency 
    from .views import main
    app.register_blueprint(main)
    return app
The views.py come with this source code:
from flask import Blueprint
from flask import jsonify, request
from . import db
from .models import Texts

main = Blueprint('main', __name__)
@main.route('/add_text', methods = ['POST'])
def add_text():
    txt_data = request.get_json()
    new_txt = Texts(title=txt_data['title'], txt_content=txt_data['txt_content'])
    db.session(new_txt)
    db.session.commit()
    # 201 status code for create successfully
    return 'Done', 201
@main.route('/texts/')
def texts():
    txt_list=Texts.query.all()
    texts=[]
    for txt in txt_list:
        texts.append({'title': txt.title, 'txt_content':txt.txt_content})
    return jsonify ({'texts':texts})
The models.py has this source code:
# import db from base folder, see dot
from . import db 

class Texts(db.Model):
    # primary key 
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(50))
    txt_content = db.Column(db.String(1000))
Use the base folder of the blue_test folder to instantiate the database named texts.sqlite with a table texts.
C:\Python373>cd my_flask

C:\Python373\my_flask>python
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD6
4)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from blue_test.models import Texts
>>> from blue_test import db, create_app
>>> db.create_all(app=create_app())
>>> exit()
If not run into the base folder then you get this error:
    from . import db
ImportError: attempted relative import with no known parent package
Now you will have a texts.sqlite file for the database.
Use this command to set FLASK_APP:
C:\Python373\my_flask>set FLASK_APP=blue_test
C:\Python373\my_flask>flask run
Now, using the postman you can test it by running the python script and call these methods.



Sunday, August 4, 2019

Python 3.7.3 : Using the flask - part 008.

The tutorial for today will show you how to understand the flash method and fix exceptions.
First, the Flask module contains a flash method which passes a message to the next request, which generally is a template.
This lets you create feedback to users of a web application is critical, from notifications and error messages to warnings and progress alerts.
This system allows us to record a message at any point within a request, then display it at the start of the next request (and only the next request), see the documentation.
You need to import the flash with:
from flask import flash
The flash function takes up to 2 arguments, a message and a category like this: flash("message", "category").
In the next example, the random range output named out will send a flash message by category.
The flash warning category will send the number get by the random and will be into a range of 1 and 3.
Flashed messages are stored in the session until they are read it.
The HTML5 page named home.html can be found at my GitHub project.
This source code will send one message by flash and show two messages into a webpage.
@app.route('/',methods = ['GET','POST'])
def home():
    # test flash message
    out = random.randint(1,10)
    if out in range(1,3):
        flash(str(out),"warning" )
    if out in range(4,6):
        flash("This is a flash test for home.html with result:","success")
    if out in range(7,10):
        flash("This is a flash test for home.html with result:","danger")  
    return render_template("home.html")
The next example shows you how to use flash and exceptions to create an output error with render_template_string.
The output exception sends by flash without an HTML5 page request.
from flask import render_template_string
...
# fix Exception error , like 404
@app.errorhandler(Exception)
def page_not_found(e):
    flash(e, type(e))  
    return render_template_string('''
      {% with messages = get_flashed_messages(with_categories=true) %}
        {% if messages %}
          {% set printed_messages = dict() %}
          {% for category, message in messages %}
            {% if message not in printed_messages %}
              
{{message}}
{% set x = printed_messages.__setitem__(message, "value") %} {% endif %} {% endfor %} {% endif %} {% endwith %} ''')
If you put a bad path URL intro the server ( http://127.0.0.1:5000/bad ) then you get the result of the exception 404:
404 Not Found: The requested URL was not found on the server. If you entered the URL manually please check your spelling and try again.
Using the flash you can create your own notification system.

Saturday, August 3, 2019

Python 3.7.3 : Using the flask - part 007.

This will be a long tutorial because will try to link some information's from the last tutorials.
First, the structure of the project can see into my GitHub project.
I create new templates and another python script named tserv.py for testing.
You can see easier how the POST method works and how to deal with a python database issue.
This script comes with an upload file feature and upload database with sqlite3 python module.
First, for upload a file we need the HTML5 file from templates folder named upload.html.
I update the base.html file to use the bootstrap framework.
import sqlite3
class UploadForm(FlaskForm):
    file = FileField()
    submit = SubmitField("submit")
    
@app.route('/upload',methods = ['GET','POST'])
def upload():
    form = UploadForm()
    
    if request.method == "POST" and form.validate():
        if form.validate_on_submit():
            file_name = form.file.data
            file_database(name = file_name.filename,data = file_name.read())
            print("File {}".format(file_name.filename))
            return render_template("upload.html", form = form)
    return render_template("upload.html", form = form)
def file_database(name,data):
    con=sqlite3.connect("file_upload.db")
    cursor = con.cursor()
    cursor.execute("""CREATE TABLE IF NOT EXISTS my_table (name TEXT, data BLOP) """)
    cursor.execute("""INSERT INTO my_table (name , data ) VALUES (?,?) """, (name, data))
    con.commit()
    cursor.close()
    con.close()
Let's run it:
python tserv.py
Into the main folder a database will be create and will fill with the file uploaded.
Now, if you want to add more we can create a download button into our UploadForm, is no need to have another python class.
First create your form tag into upload.html file and link with the python tserv.py code show bellow:
from flask import send_file
from io import BytesIO
...
@app.route('/download', methods=['GET','POST'])
def download():
    form = UploadForm()
    if request.method == "POST":
        con = sqlite3.connect("file_upload.db")
        cursor = con.cursor()
        cur_ex = cursor.execute(""" SELECT * FROM my_table """)
        for i in cur_ex.fetchall():
            name=i[0]
            data=i[1]
            break
        con.commit()
        cursor.close()
        con.close()
        return send_file(BytesIO(data), attachment_filename='test', as_attachment=True)
    return render_template("home.html", form = form)
When you run it the download button will download the first file upload into database.
This example tutorial can be more complex.
For example, you can show the database content into a new HTML file and then save with an open dialog to disk.

Friday, August 2, 2019

Python 3.7.3 : Using the flask - part 006.

Today I will show you how to use the RESTful API application with flask python module that uses HTTP requests to GET, PUT, POST and DELETE data.
When HTTP is used, as is most common, the operations (HTTP methods) available are GET, HEAD, POST, PUT, PATCH, DELETE, CONNECT, OPTIONS and TRACE.[2], see the Wikipedia article.
All of these HTTP methods will be tested with postman software.
You need to have an account and use the downloaded software in order to interrogate with these methods.
Let's see the source new code first:
@app.route("/users/", methods=['GET'])
def users():
    users = User.query.all()
    #return users_schema.jsonify(users)
    all_users = users_schema.dump(users)
    return jsonify(all_users.data)

@app.route("/users/", methods=['POST'])
def user_post(id):
    user_post = User.query.get(id)
    print(user_post)
    username = request.json['username']
    email = request.json['email']
    user_post.username = username
    user_post.email = email
    db.session.commit()
    return user_schema.jsonify(user_post)

@app.route("/users/", methods=['PUT'])
def user_put(id):
    user_put = User.query.get(id)
    print(user_put)
    username = request.json['username']
    email = request.json['email']
    user_put.username = username
    user_put.email = email
    db.session.commit()
    return user_schema.jsonify(user_put)

@app.route("/users/", methods=['DELETE'])
def user_delete(id):
    user_delete = User.query.get(id)
    print(user_delete)
    db.session.delete(user_delete)
    db.session.commit()
    return user_schema.jsonify(user_delete)
Using the postman you can test it by running the python script and call these methods at http://127.0.0.1:5000/users/.

Thursday, August 1, 2019

Python 3.7.3 : Using the flask - part 005.

In the last tutorial, I used the flask-sqlalchemy python module.
Today I will show you how to use the flask_marshmallow python module.
First, let's take a look at this python module, see the official webpage:
Flask-Marshmallow is a thin integration layer for Flask (a Python web framework) and marshmallow (an object serialization/deserialization library) that adds additional features to marshmallow, including URL and Hyperlinks fields for HATEOAS-ready APIs. It also (optionally) integrates with Flask-SQLAlchemy.
The base class User will need to be integrated with this python module:
from flask import Flask
from flask import render_template
from forms import SignUpForm
from flask import request

from flask import jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_marshmallow import Marshmallow
import os
from forms import AddUser

app = Flask (__name__)
app.config['SECRET_KEY'] = 'abcdefg'
# set SQLAlchemy
basedir = os.path.abspath(os.path.dirname(__file__))
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'server.sqlite')
db = SQLAlchemy(app)
ma = Marshmallow(app)
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)

    def __init__(self, username, email):
        self.username = username
        self.email = email
    '''
    def __rep_(self):
        return '' % self.username
    '''
class UserSchema(ma.ModelSchema):
    class Meta:
        model = User
user_schema = UserSchema()
users_schema = UserSchema(many=True)

@app.route("/users/", methods=['GET'])
def users():
    users = User.query.all()
    #return users_schema.jsonify(users)
    all_users = users_schema.dump(users)
    return jsonify(all_users.data)

# the default name main
if __name__ == '__main__':
    app.run(debug=True)
Let's take a look at http://127.0.0.1:5000/users/ and see the result:
[
  {
    "email": "catafest@yahoo.com", 
    "id": 1, 
    "username": "catafest"
  }, 
  {
    "email": "test@test.com", 
    "id": 2, 
    "username": "user_test"
  }
]

Tuesday, July 30, 2019

Python 3.7.3 : Using the flask - part 004.

The goal of this tutorial is to interact with the database in order to use it with flask_sqlalchemy python module.
The db.Model is used to interact with the database.
A database doesn't need a primary key but if you using the flask-sqlalchemy you need to have it for each one table in order to connect it.
Let's see the database:
C:\Python373\my_flask>python
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD6
4)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
>>> db.create_all()
>>> db.engine.table_names()
['user']
Let's add some data into database on user table:
C:\Python373\my_flask>python
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD6
4)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
>>> from server import User
>>> first_user = User(username='catafest',email='catafest@yahoo.com')
>>> db.session.add(first_user)
>>> db.session.commit()
>>> test_user = User(username='test',email='test@test.com')
>>> db.session.add(test_user)
>>> db.session.commit()
Update is a simple issue.
Let's update the username test_user from test to user_test:
>>> test_user.username = 'user_test'
>>> db.session.commit()
The delete is simple like the add:
>>> db.session.delete(test_user)
>>> db.session.commit()
Let's use query:
>>> results=User.query.all()
>>> results[0].username
'catafest'
>>> results[0].email
'catafest@yahoo.com'
>>> results
The next step is an important issue because let you to see how result by content and query and filter by first result:
>>> q1 = User.query.filter_by(username='catafest')
>>> q1
...flask_sqlalchemy .basequery= ...
>>> print(q1)
SELECT user.id AS user_id, user.username AS user_username, user.email AS user_email
FROM user
WHERE user.username = ?
>>> q2 = User.query.filter_by(username='catafest').first()
>>> q2
< User 1 >
>>> print(q2)
< User 1 >
>>> print(q1.username)
Traceback (most recent call last):
  File "", line 1, in 
AttributeError: 'BaseQuery' object has no attribute 'username'
>>> print(q2.username)
catafest
>>> print(q2.username,q2.email)
catafest catafest@yahoo.com 
In this case because the first is limited to one result the print of q2 is the correct way.

Monday, July 29, 2019

Python 3.7.3 : Using the twitter python module - part 003.

Today I will speak about twitter python module with the new changes of the A.P.I.
This two tutorial will not work now because the twitter A.P.I is changed.
The reason I don't delete it is the similar flow programming and access the A.P.I.:
Let's start with the install of this python module with Python version 3.7.3:
C:\Python373>cd Scripts

C:\Python373\Scripts>pip install python-twitter
...
Installing collected packages: python-twitter
Successfully installed python-twitter-3.5
Let's test the GetSearch.
You need to create a twitter application to have access to the tokens and secret keys:
import os
import json
import twitter
from twitter import *
CONSUMER_KEY=""
CONSUMER_SECRET=""

ACCESS_TOKEN=""
ACCESS_TOKEN_SECRET=""
LANGUAGES="En"
at=input("ACCESS_TOKEN: ", )
ats=input("ACCESS_TOKEN_SECRET: ", )
ck=input("CONSUMER_KEY: ", )
cs=input("CONSUMER_SECRET: ", )
api = Api(ck, cs, at, ats)
def main():
    print("Search by query using the GetSearch ")
    r = api.GetSearch(raw_query="q=twitter%20&result_type=recent&since=1999-03-07&count=100")
    print(r)
if __name__ == '__main__':
    main()
The result will be something like this:
...
@GeorgePapa19 @realDonaldTrump Sure Did https://t.co/GblrSOsaJg'), Status(ID=115
5787444525993984, ScreenName=MD__PCY, Created=Mon Jul 29 10:29:34 +0000 2019, Te
xt='mal ako ni twitter https://t.co/lRA1BOyf6a'), Status(ID=1155787444517838849,
 ScreenName=Elyse95, Created=Mon Jul 29 10:29:34 +0000 2019, Text='????? ????? ?
??? ..??? ???? ????????? ????? ????? ????? ?????? ??? ???????? .. !!    ... http
s://t.co/weChoAPDnC. https://t.co/34D2nmtbOz'), Status(ID=1155787444517781504, S
creenName=chrichacham123, Created=Mon Jul 29 10:29:34 +0000 2019, Text='RT @John
JCrace: Project Blind Faith! https://t.co/2mpB0MC540'), Status(ID=11557874445134
72514, ScreenName=318520_mu, Created=Mon Jul 29 10:29:34 +0000 2019, Text='31-85
20 ????????\n???????? → ???twitter??????????????\n??...?\n\nhttps://t.co/oVET5Z9
wXq')]

Sunday, July 28, 2019

Python 3.7.3 : Using the flask - part 003.

Another tutorial with python 3.7.3 and flask python module.
In the last tutorial, I speak about some tricks and tips.
Today, I will show some steps for fixing and run with flask-sqlalchemy.
The source code from my GitHub account can be updated with this source code.
app = Flask (__name__)
app.config['SECRET_KEY'] = 'abcdefg'
# set SQLAlchemy
basedir = os.path.abspath(os.path.dirname(__file__))
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'server.sqlite')
db = SQLAlchemy(app)
ma = Marshmallow(app)
class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)

    def __init__(self, username, email):
        self.username = username
        self.email = email
If you run it then you get this:
C:\Python373\my_flask>python
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD6
4)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
C:\Python373\lib\site-packages\flask_sqlalchemy\__init__.py:835: FSADeprecationW
arning: SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and will be dis
abled by default in the future.  Set it to True or False to suppress this warnin
g.
  'SQLALCHEMY_TRACK_MODIFICATIONS adds significant overhead and '
You will have a database file named server.sqlite.
#app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
Let's create and show the database:
C:\Python373\my_flask>python
Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 22:22:05) [MSC v.1916 64 bit (AMD6
4)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> from server import db
>>> db.create_all()
>>> db.engine.table_names()
['user']
A good approach is to create a config.py file and used into the application area.
The config.py file will have this source code:
SQLALCHEMY_TRACK_MODIFICATIONS = False
SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'server.sqlite')
DEBUG=True
The server.py has this source code:
...
app = Flask (__name__)
app.config.from_pyfile('config.py')
db = SQLAlchemy(app)
...