Storage-nio: Only com.google.cloud.storage.** should be excluded from shading

[olavloite]

There's no automatic test for this, but I did the following manual testing:

1. Before the change: Include the shaded nio library as a dependency along with the google-cloud-spanner library. It is then possible to use the nio library, but any call to Spanner fails with a NoSuchMethodError.
2. After the change: Include the shaded nio library as a dependency along with the google-cloud-spanner library. It is now possible to use both nio as Spanner without any conflicts.

Fixes#5127

[codecov]

Codecov Report

Merging #5789 into master will increase coverage by <.01%.
The diff coverage is n/a.

@@ Coverage Diff @@## master #5789 +/- ##
============================================
+ Coverage 47.17% 47.17% +<.01% + Complexity 25130 25115 -15 
============================================
Files 2389 2389 Lines 259836 259836 Branches 29417 29422 +5 ============================================
+ Hits 122585 122586 +1 + Misses 128321 128320 -1 
Partials 8930 8930

Impacted Files	Coverage Δ	Complexity Δ
...ain/java/com/google/cloud/pubsub/v1/Publisher.java	89.89% <0%> (+0.34%)	40% <0%> (ø)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 4a95f17...b959f53. Read the comment docs.

[chingor13]

cc @jean-philippe-martin

[jean-philippe-martin]

I need to look at this in more detail, but to recap just to make sure I got it right:

• The original bug is that NIO code passes an com.google.cloud.http.HttpTransportOptions around (in ways unspecified), and this object has public getter that returns a shaded shaded.cloud_nio.com.google.auth.http.HttpTransportFactory. Other code that looks at the HttpTransportOptions don't expect that type and crash
• The original bug description suggests that shading more may be a solution
• This fix does shade more (by narrowing the exception list), so the HttpTransportOptions would be shaded too.

This fix also points out a new failure mode, where including both Spanner and NIO causes Spanner to break.

[olavloite]

@jean-philippe-martin
This problem is triggered when you use the shaded version of google-cloud-storage-nio in combination with other Google Cloud libraries. The original bug originates from a user that uses google-cloud-storage-nio in combination with Big Query (see the included stack trace). I tested it with Spanner, but it will probably break with most (all?) Google Cloud libraries, as the shaded nio library does not shade its core com.google.cloud.* dependencies, but does include them in the shaded .jar. So the result is that you end up with the core Google Cloud libraries twice on the classpath.

[jean-philippe-martin]

This looks good to me. With this change in, I was able to load BigQuery and Spanner along with the NIO library and initialize them successfully.

👍

[olavloite]

@JesseLovelace Friendly ping. Do you have time to have a look at this?