Custom proto toolchain ignored

[epigramengineer]

I'm trying to write a custom protobuf toolchain to use prost instead of grpc-rust.

I've followed the guide and it seems like this should work:

load("@io_bazel_rules_rust//proto:toolchain.bzl", "rust_proto_toolchain")
rust_proto_toolchain(
    name = "proto-toolchain-impl",
    protoc = "@com_google_protobuf//:protoc",
    grpc_plugin = "//3rdparty/cargo:prost",
    proto_plugin = "//3rdparty/cargo:prost",
)
toolchain(
    name = "proto-toolchain",
    toolchain = ":proto-toolchain-impl",
    toolchain_type = "@io_bazel_rules_rust//proto:toolchain",
)

# WORKSPACE
register_toolchains("//src:proto-toolchain")

but building my rust_proto_library produces the same binary output as without the toolchain definition; it doesn't even error or produce a message. Is there a step I'm missing?

proto_library(
    name = "echo_pb",
    srcs = ["echo.proto"]
)

rust_proto_library(
    name = "echo_pb_rs",
    deps = [":echo_pb"],
)

[damienmg]

Hi you also needs to remove the rust_proto_repositories() call from you workspace file.

[epigramengineer]

Thanks!

[rdelfin]

@epigramengineer do you happen to have a sample repo with this issue resolved around? I'm trying to do the exact same thing and I can't get it to work (due to dependency and other issues)