nvidia-riva-client 2.25.1: missing `protobuf` dependency causes import-time failure

[markbackman]

Summary

v2.25.1 wheel ships _pb2.py files compiled with protoc 6.31.1, but does not declare protobuf as a dependency. pip can
install the package alongside an incompatible protobuf runtime, and the failure surfaces only at import.

Adding protobuf>=6.31.1,<7 to install requirements would let the resolver catch this before installation.

Repro

Run:

pip install "protobuf~=5.29.6" "nvidia-riva-client==2.25.1"                                                                     
python -c "import riva.client"

Produces an error:

google.protobuf.runtime_version.VersionError: Detected incompatible Protobuf Gencode/Runtime versions when loading riva/proto/riva_asr.proto: gencode 6.31.1 runtime 5.29.6.

[jmayank1511]

Fix is in review: #173

[markbackman]

Thank you!

Is there a reason why you pinned and didn't support a range, e.g.

protobuf>=6.33.5,<7

protobuf's compatibility rule is "runtime >= gencode within the same major version," so anything up to <7 will work. Pinning to an exact version makes nvidia-riva-client harder to use alongside other libraries that depend on protobuf.

[rmittal-github]

We actually saw same errors if we let protobuf update freely on the clients. As we link it with our server, it breaks too often everytime protobuf releases a new version and hence we needed to pin.

google.protobuf.runtime_version.VersionError: Detected incompatible Protobuf Gencode/Runtime versions when loading wandb/proto/wandb_settings.proto: gencode 6.32.1 runtime 6.31.1. Runtime version cannot be older than the linked gencode version. See Protobuf version guarantees at https://protobuf.dev/support/cross-version-runtime-guarantee.

We have refreshed nvidia-riva-client v2.25.1 with the fix. @markbackman you should still be able to use a protobuf runtime newer than 6.33.5 without breaking compatibility, right?

[markbackman]

This is a valuable reference:
https://protobuf.dev/support/cross-version-runtime-guarantee/

The rule is that the runtime must be >= the gencode within the same major version. The wheel for v2.25.1 ships with gencode 6.31.1, so any runtime satisfying >=6.31.1,<7 is compliant. >=6.33.5,<7 is well within that range.

Two suggestions:

1. Expand the runtime range to protobuf>=6.33.5,<7. A hard pin forces resolver conflicts with any other library in the user's environment that depends on protobuf, and it's stricter than protobuf's own compatibility guarantee requires.
2. Check the generated _pb2.py and _pb2_grpc.py files into the repo. Right now they're produced at wheel-build time by setup.py, which means the gencode version is
   opaque from the source tree and depends on whichever grpcio-tools resolved on the build machine. Checking them in pins the gencode version, makes it reviewable in PRs, removes a build-time dependency.

Also, you mentioned that you refreshed v2.25.1 with new content. In the future, could you publish a patch version, so that projects with locked dependencies can get the update to the new version? Without the version bump, most clients will not receive the update.