flask-jsonschema-validator 0.0.3

Validate Flask JSON request data with schema files and route decorators

Flask JSON Schema Validator

Validate Flask JSON request data with schema files and route decorators.

Author

Daniel 'Vector' Kerr ([e-mail])

License

Refer to LICENSE.txt.

Installation

pip install flask-jsonschema-validator

Sample Usage

Python Code

main.py

from flask import Flask, request, jsonify
from flask_jsonschema_validator import JSONSchemaValidator

app = Flask()
JSONSchemaValidator( app = app, root = "schemas" )

# Define a normal flask route, and then apply the `validate` decorator.
# Look for the `users.json` file, and use the `register` key as the schema source.
@app.route( '/register', methods = [ 'POST' ] )
@app.validate( 'users', 'register' )
def routeRegister():
  user = request.json
  return jsonify( user )

if __name__ == '__main__':
  app.run( port = 8080 )

Schema File

schemas/users.json

{
  "register": {
    "type": "object",
    "properties": {
      "name": { "type": "string", "minLength": 2, "maxLength": 100 },
      "email": { "type": "string", "format": "email" },
      "password": { "type": "string", "minLength": 8, "maxLength": 32 }
    },
    "required": [ "name", "email", "password" ]
  }
}

Run Server

python main.py

POST Data to Server

POST /register HTTP/1.0
Content-Type: application/json
Content-Length: 76

{
	"name": "fred",
	"email": "[e-mail]",
	"password": "frediscool"
}

Handling Validation Errors

If the data validates correctly then the server will respond with the POST data as a JSON object.

If the data fails to validate, a jsonschema.ValidationError exception will be raised.

To handle the exception, you could register a Flask errorhandler. For example:

import jsonschema
from flask import Response

@app.errorhandler( jsonschema.ValidationError )
def onValidationError( e ):
  return Response( "There was a validation error: " + str( e ), 400 )