A sample Flask application for backend adsabs (micro) web services. To integrate into the ADS-API, an application must expose a /resources route that advertises that application's resources, scopes, and rate limits.

GET on /resources should return JSON that looks like:

{
    "/route": {
        "scopes": ["red","green"],
        "rate_limit": [1000,86400],
        "description": "docstring for this route",
        "methods": ["HEAD","OPTIONS","GET"],
    }
}

To facilitate that, one can define that route explitictly/manually or by using flask-discoverer. This blueprint is pre-configured to do just this.

For convenience, a Vagrantfile and puppet manifest are available to facilitate development within a virtual machine. To use the vagrant VM defined here you will need to install Vagrant and VirtualBox.

• Vagrant
• VirtualBox

To load and enter the VM: vagrant up && vagrant ssh

Alternatively, you can follow these simple steps:

• virtualenv virtualenv
• source virtualenv/bin/activate
• pip install -r dev-requirements.txt
• pip install -r requirements.txt
• python cors.py

Note: cors.py will start the microservice in a simple HTTP webserver with approparite CORS headers (so that you can access localhost:5000/.... from a browser). Normally, you would run python wsgi.py or use a faster gunicorn to start wsgi.py.

To make changes to the database schema associated with the application:

• Update the database model in models.py
• execute: python manage.py db migrate
• if necessary, make manual changes in the migration scripts generated in migrations/versions (see notes below)
• execute: python manage.py db upgrade

Notes:

1. Installation of Flask-Migrate created the directory migrations. If the application uses SQLALCHEMY_DATABASE_URI as database URI, you can ignore the following remark. If the application uses SQLALCHEMY_BINDS to define the database URI, the script migrations/env.py needs a manual update: replace current_app.config.get('SQLALCHEMY_DATABASE_URI') by current_app.config.get('SQLALCHEMY_BINDS')['sample']
2. After running the migrate step, some manual editing of the migration script will be necessary because of the definition of one of the table columns: the column Column(postgresql.ARRAY(String)) gets translated into sa.Column('bar', postgresql.ARRAY(String()), nullable=True) in the migration, which will throw an exception if left unedited. The entry String() has to be changed into sa.String(). This is true in general for all types used in ARRAY.