flasker 0.1.14

Flasker

Under development.

A Flask webapp project manager with built in ORM’ed database using SQLAlchemy and Celery backend support.

• What Flasker is!

  • A transparent integration of Flask, SQLAlchemy and Celery which lets you configure these individually according to your project needs via a single .cfg file (cf. Sample config file).

  • A very simple pattern to organize your project via the current_project proxy. No more complicated import schemes!

  • A command line tool from where you can create new projects, launch the Flask buit in Werkzeug server, start Celery workers and the Flower tool, and run a shell in the current project context (inspired by Flask-Script).

  • OAuth (via Google OAuth 2) and a bunch of utilities via the util module (for convenient logging, efficient API responses, property caching, and more).

• What Flasker isn’t?

  • A simplified version of Flask, SQLAlchemy and Celery. Flasker handles the setup but purposefully leaves you free to interact with the raw Flask, Celery and database objects. Some knowledge of these frameworks is therefore required.

Quickstart

• Installation:

  $ pip install flasker

• To create a new project:

  $ flasker new basic

  This will create a default project configuration file default.cfg in the current directory (cf Config file API for more info on the available configurations through the new command).

• Editing your project:

  The flasker module exposes a current_project proxy which grants you access to the Flask app, the Celery application and the SQLAlchemy database object respectively through its attributes app, celery, db. Inside each project module (defined in the MODULES option of the configuration file) you can then do, for example:

  from flasker import current_project
  
  app = current_project.app
  
  # do stuff with the app

• Next steps:

  $ flasker -h

  This will list all available commands for that project:

  • Running the app server

  • Starting a worker for the Celery backend

  • Running the flower worker management app

  • Starting a shell in the current project context (useful for debugging)

  Extra help is available for each command by typing:

  $ flasker <insert_command> -h

Sample config file

Here is a minimalistic project configuration file:

[PROJECT]
NAME: My Project
MODULES: app.views,app.tasks
DB_URL: sqlite:///db/db.sqlite
[APP]
DEBUG: True
TESTING: True
[CELERY]
BROKER_URL: redis://
CELERYD_CONCURRENCY: 2

Config file API

The following keys are valid in the PROJECT section:

• NAME, name of the project

• MODULES, modules to import on project load

• DB_URL, URL of database (defaults to the in memory sqlite://)

• APP_STATIC_FOLDER, path to folder where the Flask static files lie (defaults to app/static)

• APP_TEMPLATE_FOLDER, path to folder where the Flask template files lie (defaults to app/templates)

• STATIC_URL, optional URL to serve static files

• OAUTH_CLIENT, cf. Using OAuth

• AUTHORIZED_EMAILS, df. Using OAuth

Note that all paths are relative to the configuration file.

The following pregenerated configurations are available through the flasker new command:

• basic, minimal configuration

• celery_dq, sets up celery direct queueing

Using OAuth

To restrict access to your webapp to some users, you will need to enter your Google Client ID (from the Google API console) in the OAUTH_CLIENT configuration option and also enter authorized emails in the AUTHORIZED_EMAILS option. Then, use the login_required decorator from Flask-Login to protect your views (cf. the docs for examples and a tutorial). The callback URL you should authorize is http://your.domain:port/oauth2callback.

Utilities

TODO

Other stuff

• Setting up Redis:

  $ curl -O http://download.redis.io/redis-stable.tar.gz
  $ tar xvzf redis-stable.tar.gz
  $ cd redis-stable
  $ make
  $ make test
  $ sudo cp redis-server /usr/local/bin/
  $ sudo cp redis-cli /usr/local/bin/

  To daemonize redis on a mac:

  Create a plist file:

  $ sudo vim /Library/LaunchDaemons/io.redis.redis-server.plist

  Copy the following contents:

  <?xml version="1.0" encoding="UTF-8"?>
  <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
  <dict>
    <key>Label</key>
    <string>io.redis.redis-server</string>
    <key>ProgramArguments</key>
    <array>
      <string>/usr/local/bin/redis-server</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
  </dict>
  </plist>

• Running the server on Apache:

  Create a file called run.wsgi in the main directory with the following contents:

  # Virtualenv activation
  from os.path import abspath, dirname, join
  activate_this = abspath(join(dirname(__file__), 'venv/bin/activate_this.py'))
  execfile(activate_this, dict(__file__=activate_this))
  
  # Since the application isn't on the path
  import sys
  sys.path.insert(0, abspath(join(dirname(__file__)))
  
  # App factory
  from app import make_app
  application = make_app()

  Then add a virtualhost in your Apache virtual host configuration file (often found at /etc/apache2/extra/httpd-vhosts.conf) with the following configuration:

  <VirtualHost *:80>
    ServerName [server_name]
    WSGIDaemonProcess [process_name] user=[process_user] threads=5
    WSGIScriptAlias / [path_to_wsgi_file]
    <Directory [path_to_root_directory]>
        WSGIProcessGroup [process_name]
        WSGIApplicationGroup %{GLOBAL}
        Order deny,allow
        Allow from all
    </Directory>
    ErrorLog "[path_to_error_log]"
    CustomLog "[path_to_access_log]" combined
  </VirtualHost>

Sources

• http://redis.io/topics/quickstart

• http://naleid.com/blog/2011/03/05/running-redis-as-a-user-daemon-on-osx-with-launchd/

• http://infinitemonkeycorps.net/docs/pph/

• https://google-developers.appspot.com/chart/interactive/docs/index

• http://codemirror.net/

• http://networkx.lanl.gov/index.html