SendGrid does not always correctly provide the sent Message-ID header value
to a tracking webhook's smtp-id field, making it unreliable to use for Anymail's
`message_id`.
Instead, generate a UUID `message_id` for Anymail tracking, and pass it from
send to webhooks in SendGrid custom args as anymail_id.
Webhooks will fall back to smtp-id for compatibility with previously-sent
messages that didn't have an anymail_id custom arg.
Fixes#108
And decide not to work around a Python 3.3 bug accessing MIME headers
that have non-ASCII characters in params. The bug is fixed in the
Python 3.4 email package (and didn't exist in Python 2.7). Python 3.3
was only supported with Django 1.8.
To conserve our ESP test accounts' send quotas, don't run
the live API integration tests 13 times in every Travis run.
Instead, just run them twice, on a representative set
of Python/Django combinations:
* Once on Python 2.7 (currently with Django 1.8)
* Once on Python 3.x (currently 3.5 with Django 1.9)
(Prep for running weekly tests on Travis cron.)
The *non*-integration tests still run on all combos.
* Introduce RUN_LIVE_TESTS environment var to control
whether live API integration test cases should run.
Default True, except in Travis-CI runs default False.
* Enable RUN_LIVE_TESTS in .travis.yml matrix for the
Python/Django combos listed above.
* csrf_exempt must be applied to View.dispatch,
not View.post.
* In base WebhookTestCase, enable Django test Client
enforce_csrf_checks. (Test Client by default disables
CSRF protection.)
Closes#19
Also includes:
* Change AnymailTestMixin.assertDoesNotWarn
to filter specific warning classes.
* Look specifically for AnymailInsecureWebhookWarning
in WebhookBasicAuthTestsMixin.test_warns_if_no_auth
(because we don't care *in that test case* about
DeprecatedInDjango10 warnings).
Previously, setting esp_extra['x-smtpapi']['filters']
would override the entire filters setting, potentially
undoing other Anymail options that use SendGrid
filters (like track_opens).
Now, 'filters' is special-cased, and merged with
any other Anymail filter options.
(We don't do a fully deep merge, because otherwise
there would be no way to use esp_extra to *clear*
Anymail settings.)
