v0.60.0 pulls in 300kLOC of additional dependencies

[tamird]

aa0f0be added a dependency on google.golang.org/grpc/xds which pulls in a lot of code.

It should be possible to upgrade past v0.60.0 without taking on all this bloat.

[codyoss]

@mohanli-ml is there anything we can do here to lower the complexity of dependencies?

[codyoss]

Can this resolver registration be moved to the site of an actual client?, or even better the program making use of our client? It seems like the bulk of the deps are related to pulling in a lot of the envoy project.

[mohanli-ml]

@menghanl @dfawley Any suggestions here?

[menghanl]

This import _ "google.golang.org/grpc/xds/googledirectpath" adds the extra dependencies.
(aa0f0be#diff-8a842d9ae06c25d12d6cf1e82d5057be6f81be7a2d75f82cc45aa28207f13023R16)

Direct path depends on xDS. To enable direct path, the library will need to pull in the xDS dependencies (including the xDS protos from the envoy project).

Is it OK for cloud libraries to not have direct path capability by default, and ask users to enable direct path?
If the answer is yes, we can delete that import and ask the users to add it.
But note that it's a code change that they will need to make.

[mohanli-ml]

Also if the decision is to move the xds dependency from the google-api-go-client repo to service repo (like bigtable-go, spanner-go), I want to know if we should also do this for other languages?

[codyoss]

@mohanli-ml I think that it should at least be moved there. But I wonder if a better pattern would be to, through docs, tell users to add the registration import themselves. Then all users of spanner and bigtable don't have to pay the cost of these deps. I am not sure what the semantics look like in other languages, but if something similar could be done there I don't think that would be a bad idea.

[dfawley]

It seems a little strange to me that client libraries would have code that requires an import (using the "google-c2p" resolver scheme), but doesn't actually do the import itself. And, it doesn't detect this scenario and fall back, either.

Maybe, instead of (or in addition to?) checking the gRPC version, it should look up the resolver and use it only if it is found? I.e. [grpc/]resolver.Get("google-c2p") != nil. Otherwise, fall back to non-directpath.

[mohanli-ml]

I will have another PR to remove the google-c2p dependence in google-api-go-client after the PR to add them to bigtable/spanner gets merged.

[codyoss]

This should have been addressed in a recent release. Closing.