improve stability of ctx.add_basemap()

[veenstrajelmer]

Fixes #247

Changed:

• made sure all HTTPErrors are captured and retried
• included the last error/reason message when max_retries is reached

The code in this contribution catches all HTTPErrors and therefore makes it impossible that the code continue with None in the arrays list. This used to cause varying errors related to None, depending on whether the first in the arrays list was None or not, or any of the others. By capturing all HTTPErrors, the code is redirected to retrying instead of that the _retryer() function returns None. After max_retries is reached, the user now gets a informative error message. The format of the message is based on what request.raise_for_status() would return.

The current code proves useful, these were the error messages during the manual tests:

• HTTPError: Connection reset by peer too many times. Last message was: 502 Error: Bad Gateway for url: https://a.tile.openstreetmap.fr/hot/10/812/458.png
• 500 Error (forgot to copy this one when it occurred

@martinfleis could you review this PR?

[veenstrajelmer]

I see some of the tests are failing because of os.wait() already taken care of in #245. But that PR also has failing tests related to this PR. If you would merge #245 I can update the branch if required, but if you have a different idea about it, please feel free to let me know or take over.

[martinfleis]

I've merged #245, you can try updating this one

[veenstrajelmer]

The branch/fork was synced, but I think you have to approve the test workflow to be kicked off again.

[martinfleis]

I believe that the remaining failures are not related.

[martinfleis]

I don't think there's a way of testing this easily so let's say this is fine as is, unless you want to tweak it further.

[veenstrajelmer]

Ok, in that case please go ahead with merging the PR. Thanks for your consideration. I would like to update the minimal contextily version in my pyproject.toml once this fix is released. Is it already know when there will be a new release or not yet?

[martinfleis]

I'll cut the patch release today.