I appreciate for the effort you’ve put to incorporate in the poll. As the survey suggests Django is by far the most voted.

We would try from the next week to focus more on Django. As many users are at the beginning of the process we’ll try to start from scratch, sorry to say so if you are a senior Django developer :(

We also talk about Docker as a 2nd most voted technology. Don’t worry about it.

As I am a full-time developer I also put other learning materials in the channel too. So be patient. within a month or two you will learn a lot :)

BONUS: we publish videos for some learning materials at the weekend. Thank you all.

NOTE: poll is open. You can still vote.

#django #python #docker #podcast #video #toturial

Dear readers,
1st and 2nd part of the basic Django course will be published until 9:00 P.M. ⌚

Installation of Django

If you have not yet installed django on your system, install it using the below command:

$ sudo pip install django
Password:
Collecting django
  Downloading Django-1.11.6-py2.py3-none-any.whl (6.9MB)
    100% |████████████████████████████████| 7.0MB 174kB/s
Requirement already satisfied: pytz in /Library/Python/2.7/site-packages (from django)
Installing collected packages: django
Successfully installed django-1.11.6

After installation you can check the validity of the Django installation:

$ python -m django --version
1.11.6

What does -m do in the above command:

-m module-name
        Searches sys.path for the named module and runs the corresponding .py file as a script.

To see list of django-admin subcommands:

$ django-admin help

Type 'django-admin help <subcommand>' for help on a specific subcommand.

Available subcommands:

[django]
    check
    compilemessages
    createcachetable
    dbshell
    diffsettings
    dumpdata
    flush
    inspectdb
    loaddata
    makemessages
    makemigrations
    migrate
    runserver
    sendtestemail
    shell
    showmigrations
    sqlflush
    sqlmigrate
    sqlsequencereset
    squashmigrations
    startapp
    startproject
    test
    testserver
Note that only Django core commands are listed as settings are not properly configured (error: Requested setting INSTALLED_APPS, but settings are not configured. You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings.)

That's it! Welcome to the Django world. :)

#python #django #installation #pip #django_part1

Now that you have installed Django successfully you need to start a project. Django has a command for project administration called django-admin, by using it you will be able to create a bare-bone project which includes database configuration, Django-specific options and application-specific settings.

Tech C**P enough, let's create the project by issuing the below command (project name: saturn):

$ django-admin startproject saturn

Suppose our project name is saturn you can name it everything you like.
cd into the folder saturn and issue ls, to see list of files created by django-admin:

$ ls
manage.py saturn

NOTE: do not call your project name django or test or anything that is somehow related to keywords, otherwise there will be conflict between your project and django.

NOTE: the project could live every where inside your server, it is not mandatory to put the code in /var/www/ as old PHP does that. It has the risk of exposing your project code to the wild west (Internet). :)

Now the overall project looks like:

saturn/
    manage.py
    saturn/
        __init__.py
        settings.py
        urls.py
        wsgi.py

OK let's run our project and see what's in there (you should be in first saturn folder):

$ python manage.py runserver
Performing system checks...

System check identified no issues (0 silenced).

You have 13 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, contenttypes, sessions.
Run 'python manage.py migrate' to apply them.

October 27, 2017 - 16:17:10
Django version 1.11.6, using settings 'saturn.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

If you have a server listening on port 8000, give your port in front of runserver command as below:

$ python manage.py runserver 8085

runserver is a minimal developement-specific server written purely in python. It reloads itself on code change. In some cases like adding a file does not trigger server reload so you have to restart it manually.

There are some warnings (ignore them at the moment), at the end it is said that project is up and running on port 8000. You can see the output in the next post.

NOTE: some future parts of the project could be in video podcast, it totally depends on your feedbacks and my time.

#python #django #runserver #startproject #django_part2

https://zaiste.net/posts/removing_docker_containers/

#docker #container #rm #remove #ps #image

Run a bash in your container:

sudo docker exec -i -t 96885e9e9a51 /bin/bash

96885e9e9a51 is container id. You have to find it yourself by using the below command:

docker ps -a

#docker #exec #bash #container

Pass arguments to Dockerfile when you build it using --build-arg in order to have greater flexibility on docker build:

docker build -t essearch/ess-elasticsearch:1.7.6 --build-arg SHARDS_NO=5

If you want to pass multiple arguments to Dockerfile give another --build-arg and give your second argument as above.
Now initiate your args inside of Dockerfile as below:

ARG SHARDS_NO=""

#docker #container #build_arg #argument #build #image

In order to remove docker images, first see your images and their corresponding id:

sudo docker images

Now to remove an image just use rmi as below:

sudo docker rmi b0c8cfb8fdb3

b0c8cfb8fdb3 is IMAGE ID to be removed.

#docker #image #rmi #remove

In the last tutorial we designed a project. Project holds the whole infrastructure, it can contain multiple apps. A weblog, an eshop page, poll app could all be an app in our newly created project. The examples are endless.

After project creation to create an app you can use startapp. For now we create a poll app:

$ python manage.py startapp polls
$

The structure of the polls app should be as below:

polls/
    __init__.py
    admin.py
    apps.py
    migrations/
        __init__.py
    models.py
    tests.py
    views.py

All the poll application logic resides here.

We try first by creating a view that return a sample http response. For writing view for your polls application you have to put it inside of views.py:

from django.http import HttpResponse


def index(request):
    return HttpResponse("Hello, world. You're at the polls index.")

Yes! That's it. We have created view in django. But for calling this view from outside you have to map a route to it. In my app I don't have the file urls.py so create it in polls and map as below:

from django.conf.urls import url

from . import views

urlpatterns = [
    url(r'^$', views.index, name='index'),
]

url is django module to implement the routing functionality.

The next step is to bind the newly defined route in polls to your project urls route. So for now go to saturn/urls.py:

from django.conf.urls import include, url
from django.contrib import admin

urlpatterns = [
    url(r'^polls/', include('polls.urls')),
    url(r'^admin/', admin.site.urls),
]

The first url says that give every route that starts with polls to polls.urls. You can see that we have used include to reference URL configuration. When it reaches /polls it removes polls and send the remaining of the URL to polls.

Now run your project with the command below and see the result:

$ python manage.py runserver

The final step is to open your browser and point it to /polls and see the result:

http://127.0.0.1:8000/polls/

Voila! Good job everybody :)

If you go to base path you will see the error below (see the picture):

#django #url #include #views #pattern #django_part3

To install your python module you need a setup.py file inside of your project. The content of the setup.py can be something like below:

setup(name=PROJECT_NAME,
       version=PROJECT_VERSION,
       description=PROJECT_DESCRIPTION,
       long_description=PROJECT_LONG_DESCRIPTION,
       author='Ali',
       author_email='info@ali.com',
       url='http://www.ali.com/',
       license='SOMETHING',
       entry_points=PROJECT_ENTRY_POINTS,
       classifiers=[],
       keywords='',
       packages=find_packages(exclude=['ez_setup', 'examples', 'tests']),
       include_package_data=True,
       namespace_packages=[],
       install_requires=['LIST', 'OF', 'REQUIREMENTS'],
       zip_safe=False,
       test_suite='nose.collector')

Now if you want to install it on your machine as a package just:

python setup.py install

If you want to upload it into your python repository:

python setup.py sdist upload -r my_repo

NOTE: you should be in the root of your project before running the previous command.

my_repo server should be declared inside of ~/.pypirc:

[distutils]
  index-servers =
      my_repo

  [my_repo]
  repository: http://pypi.repo.my_host.com:5000
  username: username
  password: password

If you want to install something from your repository via pip you have to provide the extra-index-url argument:

--extra-index-url http://username:password@pypi.repo.my_host.com:5000 --trusted-host pypi.repo.my_host.com

NOTE: you can put inside of an ENV variable in OS to access it better and in more readable way.

#python #setuppy #setup #package #pypi #private_repo #pypirc #pip #install

In this session we'll have a brief look at the settings.py file and do a migration for the saturn project.

To setup your database you need to give the credential in saturn/settings.py in the section:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}

As you see above the default database is set to sqlite3 and the NAME of the database is set to file path of db.sqlite3, if your database is set to MySQL you would have to provide the name of the database in NAME section.

ENGINE can have one of the below database bindings:

'django.db.backends.sqlite3',
'django.db.backends.postgresql',
'django.db.backends.mysql',
'django.db.backends.oracle'

If you are using a db other than sqlite like MySQL you should provide USER, PASSWORD HOST beside ENGINE and NAME.

INSTALLED_APPS is a section that contains apps used by
our project. For example for session management there is django.contrib.sessions section.

Some of these applications use database tables, so for Django apps to work properly, youn need to use migrate command
and create corresponding tables:

$ python manage.py migrate
Operations to perform:
  Apply all migrations: admin, auth, contenttypes, sessions
Running migrations:
  Applying contenttypes.0001_initial... OK
  Applying auth.0001_initial... OK
  Applying admin.0001_initial... OK
  Applying admin.0002_logentry_remove_auto_add... OK
  Applying contenttypes.0002_remove_content_type_name... OK
  Applying auth.0002_alter_permission_name_max_length... OK
  Applying auth.0003_alter_user_email_max_length... OK
  Applying auth.0004_alter_user_username_opts... OK
  Applying auth.0005_alter_user_last_login_null... OK
  Applying auth.0006_require_contenttypes_0002... OK
  Applying auth.0007_alter_validators_add_error_messages... OK
  Applying auth.0008_alter_user_username_max_length... OK
  Applying sessions.0001_initial... OK

You can see that needed tables are created as above. In case you don't need an app just comment it out from INSTALLED_APPS before running migration.

The next session we would create models for our tables and would do the real parts. :)

#python #django #settings #INSTALLED_APPS #migration #database #ENGINE #django_part4

Install a specific version of NODEJS on linux server:

https://askubuntu.com/questions/957439/how-to-install-a-specific-version-of-node-on-ubuntu-server

#ubuntu #linux #nodejs #node #versioin #installation

Install NPM packages from http or https:

npm config set registry https://registry.npmjs.org/

Sometimes because of filtering issues you need to download node packages from http so make sure to make it http:

npm config set registry http://registry.npmjs.org/

#node #npm #shit #installation #config

If you have Mac system and created bash scripts so far, there is a fun feature on OS X that you can type say command. say will say the phrase:

say hello channel users

Or let's say you have a bash script that will take a lot of time and at the end of the script your want to hear operation done successfully from your speaker:

say operation done successfully

#osx #say #command #fun

There is a command in osX called open that will open finder for you from within of your terminal.

The great thing about this command is that you can open finder when you have traversed a long path and now you want it to have inside of finder. Go to the desired directory in your terminal using cd then use:

open .

it will open you finder. :)

#osx #open #command #fun #trick