flask-ratify 0.1.3

A Flask extension adding a decorator for request validation based on jsonschema

A Flask extension for ratifying (validating) requests

This package uses the jsonschema for validating the requests. A package specific schema has been implemented on top of jsonschema to validate headers, args, and json_body.

Installation

Install the extension with using pip, or easy_install.

$ pip install -U flask-ratify

Usage

This package exposes a Flask extension which can enforce validations on selected routes. Routes can be specified as regexes as well. The package also contains a decorator, for those who prefer this approach.

flask-ratify returns status 400

Simple Usage

from flask import Flask
from flask_ratify import FlaskRatify

users_schema = {
    "POST": {
        "headers": {
            "type": "object",
            "properties": {
                "authorization": {"type": "string"}
            },
            "required": ["authorization"]
        },
        "json_body": {
            "type": "object",
            "properties": {
                "user_id": {"type": "string"},
                "email": {"type": "string", "format": "email"}
            },
            "required": ["user_id", "email"],
            "additionalProperties": False,
        },
        "args": {
            "type": "object"
            # add further validations if needed
        }
    },
    "GET": {
        # Add validations for GET
    }
}

schema = {
    "/users": users_schema
}

app = Flask(__name__)
FlaskRatify(app, schema)

@app.route("/users", methods=["POST", "GET"])
def create_user():
     = request.args.get("

Schema

flask-ratify schema follows a simple model of it’s own on top of json-schema. For better understanding of json-schema, read

• Python jsonschema package documentation

• Understanding jsonschema

{
    "endpoint": {
        "http method": {
            "headers": {
                "type": "object" # For headers this is always object
                "properties": {
                    "header_name": {"type": "string"} # header names should be lower cased,
                                                      #  rest any jsonschema element can be used
                #   ...
                },
                "required": ["header1", "header2"], # Optional
                "additionalProperties": False,      # Boolean, Optional
            },
            "args": {
                "type": "object" # For args this is always object
                "properties": {
                    "arg_name": {"type": "string"} # any jsonschema element can be used
                # ...
                },
                "required": ["arg1", "arg2"], # Optional
                "additionalProperties": False,      # Boolean, Optional
            },
            "json_body": {
                "type": "object|array|..." # json_body can follow any type as per jsonschema
                "properties": {
                    "field_name": {"type": "string"} # any jsonschema element can be used
                # ...
                },
                "required": ["field1", "field2"],   # Optional
                "additionalProperties": False,      # Boolean, Optional
            }
        }
    }
}

Troubleshooting

If things aren’t working as you expect, enable logging to help understand what is going on under the hood, and why.

logging.getLogger('flask_').level = logging.DEBUG

TODO

• Test cases

• Schema validation for debugging

• Automatic API documentation generation from schema

Contributing

Questions, comments or improvements? Please create an issue on Github

For code contributions, please create an issue and raise a pull request.

Credits

• jsonschema