Low-level transport objects should not be public @property-s

[dhermes]

The majority (11 of 12) low-level API @property-s that we use are surfaced publicly on the client. This is not intended, right?

$ git grep -B 1 -n 'def .*api(self' -- '*/google/*'
error_reporting/google/cloud/error_reporting/client.py-146-    @property
error_reporting/google/cloud/error_reporting/client.py:147:    def report_errors_api(self):
--
logging/google/cloud/logging/client.py-110-    @property
logging/google/cloud/logging/client.py:111:    def logging_api(self):
--
logging/google/cloud/logging/client.py-125-    @property
logging/google/cloud/logging/client.py:126:    def sinks_api(self):
--
logging/google/cloud/logging/client.py-139-    @property
logging/google/cloud/logging/client.py:140:    def metrics_api(self):
--
pubsub/google/cloud/pubsub/client.py-92-    @property
pubsub/google/cloud/pubsub/client.py:93:    def publisher_api(self):
--
pubsub/google/cloud/pubsub/client.py-108-    @property
pubsub/google/cloud/pubsub/client.py:109:    def subscriber_api(self):
--
pubsub/google/cloud/pubsub/client.py-124-    @property
pubsub/google/cloud/pubsub/client.py:125:    def iam_policy_api(self):
--
spanner/google/cloud/spanner/client.py-152-    @property
spanner/google/cloud/spanner/client.py:153:    def instance_admin_api(self):
--
spanner/google/cloud/spanner/client.py-162-    @property
spanner/google/cloud/spanner/client.py:163:    def database_admin_api(self):
--
spanner/google/cloud/spanner/database.py-179-    @property
spanner/google/cloud/spanner/database.py:180:    def spanner_api(self):
--
speech/google/cloud/speech/client.py-103-    @property
speech/google/cloud/speech/client.py:104:    def speech_api(self):
--
vision/google/cloud/vision/client.py-99-    @property
vision/google/cloud/vision/client.py:100:    def _vision_api(self):
$
$ git log -1 --pretty=%H  # Current commit checked out
1b482f06fa3a36e3cdeedf5b6810048ed67c727a

Other than vision, the non-GAPIC APIs that happen to use gRPC do not surface the properties publicly:

datastore/google/cloud/datastore/_http.py:252:            self._datastore_api = _DatastoreAPIOverGRPC(self, secure=secure)
datastore/google/cloud/datastore/_http.py:254:            self._datastore_api = _DatastoreAPIOverHttp(self)
bigtable/google/cloud/bigtable/client.py:284:    def _instance_stub(self):
bigtable/google/cloud/bigtable/client.py:298:    def _operations_stub(self):
bigtable/google/cloud/bigtable/client.py:312:    def _table_stub(self):

[dhermes]

@lukesneeringer Note that pubsub and logging have these as part of their "Beta" interface, which we don't want to break?

[lukesneeringer]

I would prefer leave this as-is, for a few reasons:

(1) We do want it to be considered acceptable to use the GAPIC APIs for advanced cases.
(2) I want to move Veneers toward being lighter weight in the future; adding convenience methods where needed but being less opinionated about responses. That probably is not going to happen with any existing Veneer (because it would be surface breaking in many cases) but it is the route we hope to take for simple APIs in the future.

[lukesneeringer]

I am assuming silence gives assent. Feel free to re-open if more discussion is needed.