Wait for last operation if not completed

[stephen-soltesz]

The Autojoin API deployment includes three distinct steps in production:

1. deploy the autojoin App Engine service
2. deploy the openapi endpoints API
3. deploy the dispatch.yml to direct requests to this service for custom domain names

While step 2 will return successfully, the operation it creates is not yet "COMPLETE" by the time step 3 begins, which generates a build error like the one below.

This change adds an explicit operation wait on that operation before continuing to step 3.

Build error:

Step #2: ERROR: (gcloud.app.deploy) Apps instance [mlab-autojoin] is the
subject of a conflict: Cannot operate on apps/mlab-autojoin because an
operation is already in progress for apps/mlab-autojoin by e309c37c-1c30-4074-9c06-4805a0935b05.

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This change is 

[coveralls]

Pull Request Test Coverage Report for Build 12039568963

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 98.92%

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Totals
Change from base Build 12038119053:	0.0%
Covered Lines:	1191
Relevant Lines:	1204

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💛 - Coveralls

[stephen-soltesz]

Not ready for review yet

[stephen-soltesz]

Okay - PTAL?

[nkinkade]

This reminded me that I had hit this very same issue earlier this year:

https://github.com/m-lab/visualizations/pull/10/files

I had tried to use the operations wait functionality, but there was a bug in it and I just fell back on using sleep with a safe amount of time. Your implementation is very similar to what I had originally in the PR above, but I found that sometimes the command substitution didn't return anything due to likely very tight timings, and when that happens the entire command fails, and the build fails too. I'm wondering if your solution might run into the same issue?

Reviewable status: 0 of 1 approvals obtained

[stephen-soltesz]

Oh, it definitely could - the || : was meant to catch the case where the wait operation fails, either for the reason you describe or any other.

What do you think?

Reviewable status: 0 of 1 approvals obtained

[nkinkade]

Got it. Sorry I missed that bit. LGTM.

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! 1 of 1 approvals obtained