layaberr 2.2.0

Exceptions handling for layab

To be able to throw exceptions in your code and send a proper HTTP response automatically to your client your need to add error handler(s) to your API and endpoints.

Add all handlers at once

from flask_restplus import Resource
import layaberr

api = None # Your flask-restplus API instance
error_responses = layaberr.add_error_handlers(api)

@api.route("/your_endpoint")
@api.doc(**error_responses)
class YourFlaskRestPlusResource(Resource):
    def get(self):
        return "test"

Add some handlers

from flask_restplus import Resource
import layaberr

api = None # Your flask-restplus API instance
error_response = layaberr.add_failed_validation_handler(api)

@api.route("/your_endpoint")
class YourFlaskRestPlusResource(Resource):
    @api.response(error_response)
    def get(self):
        return "test"

Supported Exceptions

The following exceptions are handled:

ValidationFailed

In case your endpoint raises ValidationFailed, an HTTP error 400 (Bad Request) will be sent to the client.

Error not specific to a field in received data

This code:

from layaberr import ValidationFailed

received_data = None
raise ValidationFailed(received_data, message="This is the error message")

Will result in the following JSON response sent to the client:

{"fields":  [{"item":  1, "field_name":  "", "messages": ["This is the error message"]}]}

Error specific to a field in a received dictionary

This code:

from layaberr import ValidationFailed

received_data = {"field 1": "value 1"}
raise ValidationFailed(received_data, errors={"field 1": ["Invalid value"]})

Will result in the following JSON response sent to the client:

{"fields":  [{"item":  1, "field_name":  "field 1", "messages": ["Invalid value"]}]}

Error specific to a field in a received list of dictionaries

This code:

from layaberr import ValidationFailed

received_data = [{"field 1": "value 1"}, {"field 1": "value 2"}]
raise ValidationFailed(received_data, errors={1: {"field 1": ["Invalid value"]}})

Will result in the following JSON response sent to the client:

{"fields":  [{"item":  2, "field_name":  "field 1", "messages": ["Invalid value"]}]}

ModelCouldNotBeFound

In case your endpoint raises ModelCouldNotBeFound, an HTTP error 404 (Not Found) will be sent to the client.

This code:

from layaberr import ModelCouldNotBeFound

requested_data = None
raise ModelCouldNotBeFound(requested_data)

Will result in the following JSON response sent to the client:

{"message":  "Corresponding model could not be found."}

BadRequest

In case your endpoint raises BadRequest, an HTTP error 400 (Bad Request) will be sent to the client.

This code:

from werkzeug.exceptions import BadRequest

raise BadRequest("The exception message")

Will result in the following JSON response sent to the client:

{"message":  "The exception message"}

Unauthorized

In case your endpoint raises Unauthorized, an HTTP error 401 (Unauthorized) will be sent to the client.

This code:

from werkzeug.exceptions import Unauthorized

raise Unauthorized("The exception message")

Will result in the following JSON response sent to the client:

{"message":  "The exception message"}

Forbidden

In case your endpoint raises Forbidden, an HTTP error 403 (Forbidden) will be sent to the client.

This code:

from werkzeug.exceptions import Forbidden

raise Forbidden("The exception message")

Will result in the following JSON response sent to the client:

{"message":  "The exception message"}

Exception (this is the default handler)

In case your endpoint raises an Exception, an HTTP error 500 (Internal Server Error) will be sent to the client.

This code:

raise Exception("The exception message")

Will result in the following JSON response sent to the client:

{"message":  "The exception message"}

How to install

1. python 3.6+ must be installed
2. Use pip to install module:

python -m pip install layaberr