Flask-Micron

Flask-Micron is a pluggable, method-oriented API framework for Python, focusing on security and productivity. It is built on top of the excellent Flask microframework.

The main goal for the project is to make it really simple for developers to write microservice-style JSON webservices, honoring best practices for security, and without having to pollute business logic code with HTTP request handling knowledge.

Example code

Here's the mandatory "Hello, world!" example for Flask-Micron:

from flask import Flask
from flask_micron import Micron

app = Flask(__name__)
micron = Micron(app)

@micron.method()
def hello_world(name='World'):
    return 'Hello, %s!' % name

As you can see, Flask-Micron is a layer on top of Flask. A decorator is provided, to add Python functions to the Flask-Micron request handling.

This code adds the route /hello_world to Flask. POST requests for that route are handled by Flask-Micron, which takes care of:

• reading, deserialzing and normalizing the JSON request body
• calling the hello_world() function
• creating a JSON response based on the function's return value.

Flask-Micron's main feature in action here, is that the function does not require any boiler plate code to make all this work.

Running the example code

To run the code, you can save the example code to hello.py and then start a server for it:

$ export FLASK_APP=hello.py
$ flask run
 * Running on http://127.0.0.1:5000/

Another way would be to add the following code to hello.py:

if __name__ == '__main__':
    app.run()

and run the script:

$ python hello.py
 * Running on http://127.0.0.1:5000/

Note: for production, this is not the best way to run your app, but this is very useful for development purposes. For deployment in production, take a look at the Flask deployment documentation.

Let's call it!

Now the app is running, we can send a POST request to it. Let's give this baby a spin using the Curl tool:

$ curl \
    -X POST \
    -H "Content-Type: application/json" \
    -d '"John Smith"' \
    http://127.0.0.1:5000/hello_world

Note that we use "John Smith" for the data here, which is the JSON representation for a string. The response for this request contains a JSON encoded greeting:

"Hello, John Smith!"

Because a default value is provided for the argument in the function definition, we can omit the data in the request:

$ curl \
    -X POST \
    -H "Content-Type: application/json" \
    http://127.0.0.1:5000/hello_world

This results in:

"Hello, World!"