Flask error handling: "Response object is not iterable"

Question

I'm trying to set of a REST web service using Flask. I'm having a problem with the error handling @app.errorhandler(404)

#!flask/bin/python
from flask import Flask, jsonify, abort

app = Flask(__name__)

@app.errorhandler(404)
def not_found(error):
    return jsonify({'error':'not found'}), 404

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

When I cURL it, I get nothing. In my debugger, it's telling me I have a TypeError: 'Response' object is not iterable

I used jsonify in another method with a dictionary with no problem, but when I return it as an error, it doesn't work. Any ideas?

Answer 1

from flask import Flask, jsonify

app = Flask(__name__)

@app.errorhandler(404)
def not_found(error):
    return jsonify({'error':'not found'}), 404

app.run()

With code above, curl http://localhost:5000/ give me:

{
  "error": "not found"
}

Are you using flask.jsonify?

Answer 2

As mentioned in the comments for the previous answer, that code isn't supported on Flask 0.8, and would require 0.9 or higher. If you need to support Flask 0.8, here is a compatible version that assigns the "status_code" instead:

@app.errorhandler(404)
def not_found(error):
    resp = jsonify({'error':'not found'})
    resp.status_code = 404
    return resp