I am building an API using Flask and Flask-Restful. The API might be accessed by different sort of tools (web apps, automated tools, etc.) and one of the requirement is to provide different representations (let's say json and csv for the sake of the example)
As explained in the restful doc, it's easy to change the serialization based on the content type, so for my CSV serialization I've added this:
@api.representation('text/csv')
def output_csv(data, code, headers=None):
#some CSV serialized data
data = 'some,csv,fields'
resp = app.make_response(data)
return resp
And it's working when using curl and passing the correct -H "Accept: text/csv" parameter.
The issue is that since some browsers might be routed to a url directly to download a csv file, I would like to be able to force my serialization via a url parameter for example http://my.domain.net/api/resource?format=csv where the format=csvwould have the same effect as -H "Accept: text/csv".
I've gone through both Flask and Flask-Restful documentation and I don't see how to correctly handle this.
Simply create a sub-class of Api and override the mediatypes method:
from werkzeug.exceptions import NotAcceptable
class CustomApi(Api):
FORMAT_MIMETYPE_MAP = {
"csv": "text/csv",
"json": "application/json"
# Add other mimetypes as desired here
}
def mediatypes(self):
"""Allow all resources to have their representation
overriden by the `format` URL argument"""
preferred_response_type = []
format = request.args.get("format")
if format:
mimetype = FORMAT_MIMETYPE_MAP.get(format)
preferred_response_type.append(mimetype)
if not mimetype:
raise NotAcceptable()
return preferred_response_type + super(CustomApi, self).mediatypes()