Add an event in the event chain for transforming retrieved data from the upstream datasource before its rendered into the response.

[davidjreese]

It would be useful to transform data retrieved by the upstream datasource (mongoDB fo example). Manipulating that as a dict object and then passing the parsed result along so that Eve can use it to generate the response.data field later on.

something like what I have below is what I am thinking:

# not sure if context is required, but it may be useful to support conditional logic based on knowing the caller URI, users session or some other kind of details.
def people_callback(context,data):
    customData = dict()
    customData['something'] = _code_to_make_something_
    for k,v in data.iteritems():
        v['somethingElse'] = _code_to_make_something_else_
        customData[k] = v
    return customData

`...'

app.on_get_on_read_people += people_callback