Build a comprehensive test suite

[dankrause]

Most tests would require interacting with the dev_appserver, and I'm not yet sure what that will mean for their design.

[dankrause]

Some useful information that came up in a quick search: https://developers.google.com/appengine/docs/python/tools/localunittesting

If I have some time later today, I'll get started on this.

[dankrause]

Interesting problem: rest_gae.RestHandlerClass acts like a webapp2.RequestHandler (and in fact, is a subclass of it). However, it is also a subclass of webapp.RequestHandler (notice the lack of the number two there) via the blobstore_handlers that it subclasses. This actually breaks the webapp2 unit testing helpers. The helpers check to see if your handler is a subclass of webapp.RequestHandler first, and if so, treat it like one. This fails because we're acting like a webapp2.RequestHandler, and requiring the request and response objects as args to rest_gae.RestHandlerClass.__init__, but webapp2 doesn't pass them while testing. I'm not 100% sure why testing via Request.get_response acts that much differently than normal use of webapp2, but it does.

I'm still trying to figure out the best way to work around this.

[dankrause]

I think that the best way to fix this might be to refactor how we implement blobkey property handlers. The way I see it, RESTHandlerClass should only be for models and instances. We would call get_rest_class in RESTHandler, and we'd call a new get_blobstore_class for each BlobKeyProperty which would build a handler that subclasses both BlobstoreUploadHandler and BlobstoreDownloadHandler (and not webapp2.RequestHandler).

I think this would actually end up simplifying RESTHandlerClass for us, by stripping away the blobstore stuff and keeping it in one place. I'm still thinking about this one.

[budowski]

That's what I initially thought of doing - the problem was without subclassing from BaseRESTHandler, those blob handlers would lose any permission-based checking - e.g. is the user permitted to POST to /my_model/123/blob_prop? (and this would mean we'd have to write the same code twice - in both classes). Maybe now, with the new permission system you're writing - could there be a DRY-friendly way of doing this?

[signalpillar]

@budowski could you please tell whether you have some progress with this issue ?

[signalpillar]

Could you please check this version, where we do not inherit but aggregate instances of download/upload handlers when needed.

What I can see from the code of these helpers they rely on the request and response parameters and do not rely on the method overridden in our RESTHandlerClass.

[signalpillar]

I have added simple tests also. The show that rest_gae can be used in testing but they do not prove that upload/download for blogs works correctly.