Small tweaks to Connection in storage; towards a cleaner API.

[dhermes]

• Making Connection.make_request non-public
• Making Connection.build_api_url a class method

[coveralls]

Coverage remained the same at 100.0% when pulling 53f6b86 on dhermes:storage-connection-tweaks into d858ff0 on GoogleCloudPlatform:master.

[tseaver]

I don't understand the motivation for making build_api_url a class method: all the callers call it via the connection instance, and then have to pass in that instance's project.

[dhermes]

The motivation doesn't precisely fit the problem. I noticed that we had an instance method here (storage) and a class method in datastore.

But the true motivation was making it to that each Connection instance only had public methods for making a single API request. Any other features would be moved elsewhere (like #583).

I'm still trying to figure out if / how build_api_url fits into that idea.

[dhermes]

@tseaver Rebased on top of #580. PTAL (my new comment above).

[coveralls]

Coverage remained the same at 100.0% when pulling 9dc8773 on dhermes:storage-connection-tweaks into 9518db7 on GoogleCloudPlatform:master.

[tseaver]

Given that it needs instance state (the project), I can't see any benefit to making it a class method. I can even imagine that having it stay an instance method would be useful for https://github.com/GoogleCloudPlatform/gcloud-meta/issues/4

[dhermes]

Cool. Closing this out.

[tseaver]

FWIW, I can certainly see making both build_api_url and make_request private.

[dhermes]

@tseaver OK I'll put that in motion and send a PR.

This means build_api_url should be private in datastore as well.

How do you feel about making them private functions in the connection modules? The only reason they are attached to the Connection objects are because of the class constants which could just as easily be module constants. (Though without looking at the code it may be a PITA to import the connection module in places where a Connection object was used freely.)