cleanup(pubsub): delete topics older than 3 days

[alevenberg]

Ran once, went from 180 topics -> 40.

I think we might be able to delete some more (cloud-cpp) too, but I will check with someone before adding that

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This change is 

[codecov]

Codecov Report

Attention: 14 lines in your changes are missing coverage. Please review.

Comparison is base (1d7f699) 93.25% compared to head (070e95b) 93.26%.
Report is 7 commits behind head on main.

Files	Patch %	Lines
google/cloud/pubsub/samples/topic_admin_samples.cc	74.07%	14 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #13556   +/-   ##
=======================================
  Coverage   93.25%   93.26%           
=======================================
  Files        2196     2196           
  Lines      191202   191253   +51     
=======================================
+ Hits       178307   178363   +56     
+ Misses      12895    12890    -5     

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[scotthart]

Reviewable status: 0 of 1 files reviewed, 4 unresolved discussions (waiting on @alevenberg)

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google/cloud/pubsub/samples/topic_admin_samples.cc line 39 at r1 (raw file):

    google::cloud::pubsub_admin::TopicAdminClient& topic_admin_client,
    std::string const& project_id, absl::Time time_now) {
  std::cout << "Cleaning up old topics...\n";

If this was a debug comment, please remove it. If instead it's adding to the output of the sample code, feel free to leave it.

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google/cloud/pubsub/samples/topic_admin_samples.cc line 40 at r1 (raw file):

    std::string const& project_id, absl::Time time_now) {
  std::cout << "Cleaning up old topics...\n";
  auto const parent = google::cloud::Project(project_id).FullName();

Do we need to create a variable here or can the function call be the argument to ListTopics?
There's actually a few places where you create a variable and only use it once. They might not all be necessary.

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google/cloud/pubsub/samples/topic_admin_samples.cc line 41 at r1 (raw file):

  std::cout << "Cleaning up old topics...\n";
  auto const parent = google::cloud::Project(project_id).FullName();
  for (auto& topic : topic_admin_client.ListTopics(parent)) {

Can this be auto const&?

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google/cloud/pubsub/samples/topic_admin_samples.cc line 44 at r1 (raw file):

    if (!topic) continue;
    auto topic_name = topic->name();
    std::string keyword = "cloud-cpp-samples";

This could be const.

[alevenberg]

Reviewable status: 0 of 1 files reviewed, 5 unresolved discussions (waiting on @devbww and @scotthart)

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google/cloud/pubsub/samples/topic_admin_samples.cc line 39 at r1 (raw file):

Previously, scotthart (Scott Hart) wrote…

If this was a debug comment, please remove it. If instead it's adding to the output of the sample code, feel free to leave it.

Done.

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google/cloud/pubsub/samples/topic_admin_samples.cc line 40 at r1 (raw file):

Previously, scotthart (Scott Hart) wrote…

Do we need to create a variable here or can the function call be the argument to ListTopics?
There's actually a few places where you create a variable and only use it once. They might not all be necessary.

Done.

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google/cloud/pubsub/samples/topic_admin_samples.cc line 41 at r1 (raw file):

Previously, scotthart (Scott Hart) wrote…

Can this be auto const&?

Done.

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google/cloud/pubsub/samples/topic_admin_samples.cc line 44 at r1 (raw file):

Previously, scotthart (Scott Hart) wrote…

This could be const.

Done.

[alevenberg]

Part of #12987