Dataset exists (409) / dataset still in use (DELETE --> 400)

[dhermes]

python2:

• Still in use: precise-truck-742:system_tests_160041019_1473898532
• Exists: precise-truck-742:system_tests_160041019_1473898532

then python3:

• Still in use: precise-truck-742:system_tests_160041019_1473898730
• Exists: precise-truck-742:system_tests_160041019_1473898730

From https://travis-ci.org/GoogleCloudPlatform/google-cloud-python/builds/160041019

Two proposed fixes:

• Make sure the 400 is caught and retried for "still in use"
• Use dataset IDs unique to each test (if possible)

[tseaver]

Big 👍 for avoiding shared dataset IDs.

[dhermes]

@tseaver It's unclear if #2323 (double Michael Jordan) actually will fix the 400 "still in use". But it's not worth leaving this open forever.

[tseaver]

Because testcases no longer share dataset names, there isn't going to be a case where the eventual-consistency window for one testcase deleting its dataset overlaps the creation during setup of another testcase.

[dhermes]

But the clean-up of each dataset will be a delete and the "still in use" on DELETE is where the issue came from.

[dhermes]

@tseaver Let's leave it closed until the "still in use" shows up again in the wild?

[tseaver]

Hmm, I just kicked in #2333 to address it.

[dhermes]

Oh gotcha. SGTM.