Simple Guide¶
Handle Accept Field¶
You can specify media type that you can provide with
provides().
See an example.
First, create an Flask application:
from flask import Flask
from flask.ext.negotiation import provides
app = Flask(__name__)
Make route that provides json only:
@app.route('/json')
@provides('application/json')
def json():
return '{"message": "Hi"}'
If request is not acceptable, then it returns HTTP 406 (Not Acceptable)
You can also handle media type:
@app.route('/dynamic')
@provides('application/json', 'text/html', to='media_type')
def dynamic(media_type):
if media_type == 'application/json':
return '{"message": "Hi"}'
else:
return '<html><body>Hi!</body></html>
provides will choose best media type can be handled in acceptables and give it to keyword argument named to
Render Contents¶
Render renders content with renderer choosen by Accept HTTP header
field
First, You have to define a renderer:
import json
from flask.ext.negotiation import Render
from flask.ext.negotiation.renderer import renderer, template_renderer
@renderer('application/json')
def custom_renderer(data, template=None, ctx=None):
return json.dumps({'data':data})
Then create a instance of Render:
render = Render(renderers=(template_renderer, custom_renderer))
In module defining views import render:
from . import app, render
@app.route('/data/<data_id>')
def data_view(data_id):
data = get_data(data_id)
# Let data = {'data_id':3, 'content':'secret'}
...
return render(data, 'data/view.html')
data/view.html‘s source is here:
<html>
<head>
<title>The Data Is Here</title>
</head>
<body>
{{ data['content'] }}
</body>
</html>
When we send a HTTP request to /data/3 with Accept header field text/html response will be like:
<title>
<head>
<title>The Data Is Here</title>
</head>
<body>
secret
</body>
</html>
When Accept is application/json, response will be like:
{"data": {"content": "secret", "data_id": 3}}