CORS not set, can't access JSON in Chrome

[Dragon Dave McKee]

No description provided.

[sophiebookley]

XMLHttpRequest cannot load https://newsreader.scraperwiki.com/summary_of_events_with_actor/page/1?uris.0=dbpedia:Wayne_Rooney&output=html&_=1406801162041. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8000' is therefore not allowed access.

[ian_hopkinson]

The Simple API will return JSONP if the parameter &callback=mycallback is appended to the query, I believe this is the standard way of addressing this issue.

I don't know why the parameter &_=1406801162041 is appended to the query, I don't think it matters because I believe the Simple API will silently ignore unrecognised parameters.

[Dragon Dave McKee]

This doesn't help when the request contains non-JSON material, of course.

[David Jones]

_=<randomnumber> is a semi-standard way of defeating broken caches.

[David Jones]

As per the error message, we need to add an Access-Control-Allow-Origin header.

For the JSON API on the platform we add one like this:

Access-Control-Allow-Origin: *

This is standard practice for APIs that do not require a login (most of them).

[ian_hopkinson]

@StevenMaude @drj I think I fixed this but I don't know how to test it

[Steven Maude]

@ian_hopkinson I tried the queries:

https://newsreader.scraperwiki.com/summary_of_events_with_actor/page/1?uris.0=dbpedia:John_Swofford&output=json and https://newsreader.scraperwiki.com/summary_of_events_with_actor/page/1?uris.0=dbpedia:John_Swofford&output=html

in Chromium and they seemed to load OK.

Not sure what I'd expect to see if they didn't. (I checked in developer console.)

[ian_hopkinson]

The convincing demo that this was fixed would be to try out Sophie's code on the Mac

[Steven Maude]

I can't reproduce on Firefox or Chromium, so I'm going to assume that the header change fixed it. If anyone else has this problem, we'll reopen the issue.