Fixed broken protoc toolchain in examples (#3221)

I forgot to add this to
#3219

Author: UebelAndre

examples/proto/MODULE.bazel

@@ -22,13 +22,10 @@ local_path_override(
 #
 # Rules for protobuf / gRPC
 # https://github.com/bazelbuild/rules_proto/releases
-bazel_dep(name = "rules_proto", version = "6.0.2")
-
-# https://github.com/aspect-build/toolchains_protoc/releases
-bazel_dep(name = "toolchains_protoc", version = "0.3.1")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 
 # https://registry.bazel.build/modules/protobuf
-bazel_dep(name = "protobuf", version = "27.1")
+bazel_dep(name = "protobuf", version = "29.0", repo_name = "com_google_protobuf")
 
 # https://github.com/bazel-contrib/toolchains_llvm
 bazel_dep(name = "toolchains_llvm", version = "1.2.0")
@@ -75,7 +72,10 @@ use_repo(rust, "rust_toolchains")
 register_toolchains("@rust_toolchains//:all")
 
 # Custom Prost toolchain
-register_toolchains("@//build/prost_toolchain")
+register_toolchains(
+    "@//build/prost_toolchain",
+    "@//build/proto_toolchain",
+)
 
 ###############################################################################
 # R U S T  C R A T E S

examples/proto/README.md

@@ -47,11 +47,9 @@ In your MODULE.bazel, you add the following:
 # rules for proto
 ###############################################################################
 # https://github.com/bazelbuild/rules_proto/releases
-bazel_dep(name = "rules_proto", version = "6.0.2")
-# https://github.com/aspect-build/toolchains_protoc/releases
-bazel_dep(name = "toolchains_protoc", version = "0.3.1")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 # https://registry.bazel.build/modules/protobuf
-bazel_dep(name = "protobuf", version = "27.1")
+bazel_dep(name = "protobuf", version = "29.0", repo_name = "com_google_protobuf")
 # rules for LLVM
 # https://github.com/bazel-contrib/toolchains_llvm
 bazel_dep(name = "toolchains_llvm", version = "1.2.0")

examples/proto/build/prost_toolchain/BUILD.bazel

@@ -23,10 +23,12 @@ rust_prost_toolchain(
     prost_types = "@crates//:prost-types",
     tonic_plugin = "@crates//:protoc-gen-tonic__protoc-gen-tonic",
     tonic_runtime = ":tonic_runtime",
+    visibility = ["//visibility:public"],
 )
 
 toolchain(
     name = "prost_toolchain",
     toolchain = "prost_toolchain_impl",
     toolchain_type = "@rules_rust_prost//:toolchain_type",
+    visibility = ["//visibility:public"],
 )

examples/proto/build/proto_toolchain/BUILD.bazel

@@ -0,0 +1,9 @@
+load("@rules_proto//proto:proto_toolchain.bzl", "proto_toolchain")
+
+package(default_visibility = ["//visibility:public"])
+
+# This macro implicitly creates `{name}_toolchain`
+proto_toolchain(
+    name = "proto",
+    proto_compiler = "@com_google_protobuf//:protoc",
+)

examples/proto_with_toolchain/MODULE.bazel

@@ -22,13 +22,10 @@ local_path_override(
 #
 # Rules for protobuf / gRPC
 # https://github.com/bazelbuild/rules_proto/releases
-bazel_dep(name = "rules_proto", version = "6.0.2")
-
-# https://github.com/aspect-build/toolchains_protoc/releases
-bazel_dep(name = "toolchains_protoc", version = "0.3.1")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 
 # https://registry.bazel.build/modules/protobuf
-bazel_dep(name = "protobuf", version = "27.1")
+bazel_dep(name = "protobuf", version = "29.0", repo_name = "com_google_protobuf")
 
 # https://github.com/bazel-contrib/toolchains_llvm
 bazel_dep(name = "toolchains_llvm", version = "1.2.0")
@@ -75,7 +72,10 @@ use_repo(rust, "rust_toolchains")
 register_toolchains("@rust_toolchains//:all")
 
 # Custom Prost toolchain
-register_toolchains("@//build/prost_toolchain")
+register_toolchains(
+    "@//build/prost_toolchain",
+    "@//build/proto_toolchain",
+)
 
 ###############################################################################
 # R U S T  C R A T E S

examples/proto_with_toolchain/README.md

@@ -33,6 +33,7 @@ While the Tonic toolchain works out of the box when its dependencies are matched
 Prost requires a custom toolchain that you have to define.
 
 The setup requires three steps to complete:
+
 1. Configure rules and dependencies in MODULE.bazel
 2. Configure a custom Prost toolchain
 3. Register custom Prost toolchain.
@@ -47,11 +48,9 @@ In your MODULE.bazel, you add the following:
 # rules for proto
 ###############################################################################
 # https://github.com/bazelbuild/rules_proto/releases
-bazel_dep(name = "rules_proto", version = "6.0.2")
-# https://github.com/aspect-build/toolchains_protoc/releases
-bazel_dep(name = "toolchains_protoc", version = "0.3.1")
+bazel_dep(name = "rules_proto", version = "7.1.0")
 # https://registry.bazel.build/modules/protobuf
-bazel_dep(name = "protobuf", version = "27.1")
+bazel_dep(name = "protobuf", version = "29.0", repo_name = "com_google_protobuf")
 # rules for LLVM
 # https://github.com/bazel-contrib/toolchains_llvm
 bazel_dep(name = "toolchains_llvm", version = "1.2.0")

examples/proto_with_toolchain/build/proto_toolchain/BUILD.bazel

@@ -0,0 +1,9 @@
+load("@rules_proto//proto:proto_toolchain.bzl", "proto_toolchain")
+
+package(default_visibility = ["//visibility:public"])
+
+# This macro implicitly creates `{name}_toolchain`
+proto_toolchain(
+    name = "proto",
+    proto_compiler = "@com_google_protobuf//:protoc",
+)

extensions/prost/MODULE.bazel

@@ -27,7 +27,7 @@ bazel_dep(
 )
 bazel_dep(
     name = "rules_proto",
-    version = "6.0.2",
+    version = "7.1.0",
 )
 bazel_dep(
     name = "protobuf",

extensions/protobuf/MODULE.bazel

@@ -27,7 +27,7 @@ bazel_dep(
 )
 bazel_dep(
     name = "rules_proto",
-    version = "6.0.2",
+    version = "7.1.0",
 )
 bazel_dep(
     name = "protobuf",