Add anthropics/connect-rust plugin v0.3.2

connect-rust is a Tower-based Rust implementation of the ConnectRPC
protocol. The plugin emits service stubs (server traits, typed clients,
monomorphic dispatchers) for the Connect, gRPC, and gRPC-Web protocols
from a single service implementation. Passes the full ConnectRPC
conformance suite.

Generated stubs reference message types via absolute Rust paths into
the buffa SDK crate (declared as a plugin dep). The plugin accepts
`extern_path=.=<rust_path>` (or shorthand `buffa_module=<rust_path>`)
to point at the buffa SDK location, same format as tonic/prost.

Crates: https://crates.io/crates/connectrpc-codegen
Repo: https://github.com/anthropics/connect-rust

Author: iainmcgin

plugins/anthropics/connect-rust/source.yaml

@@ -0,0 +1,3 @@
+source:
+  crates:
+    crate_name: connectrpc-codegen

plugins/anthropics/connect-rust/v0.3.2/.dockerignore

@@ -0,0 +1,2 @@
+*
+!Dockerfile

plugins/anthropics/connect-rust/v0.3.2/Dockerfile

@@ -0,0 +1,17 @@
+# syntax=docker/dockerfile:1.19
+FROM rust:1.91.1-alpine3.22 AS builder
+RUN apk add --no-cache musl-dev
+WORKDIR /app
+ENV CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse
+# The protoc-gen-connect-rust binary is a [[bin]] target in the
+# connectrpc-codegen crate. cargo install compiles it by crate name.
+RUN --mount=type=cache,target=/usr/local/cargo/registry,sharing=locked --mount=type=cache,target=/root/target \
+    cargo install connectrpc-codegen --version 0.3.2 --locked --root /app
+
+FROM gcr.io/distroless/static-debian12:latest@sha256:87bce11be0af225e4ca761c40babb06d6d559f5767fbf7dc3c47f0f1a466b92c AS base
+
+FROM scratch
+COPY --link --from=base / /
+COPY --link --from=builder /app/bin/protoc-gen-connect-rust /protoc-gen-connect-rust
+USER nobody
+ENTRYPOINT ["/protoc-gen-connect-rust"]

plugins/anthropics/connect-rust/v0.3.2/buf.plugin.yaml

@@ -0,0 +1,40 @@
+version: v1
+name: buf.build/anthropics/connect-rust
+plugin_version: v0.3.2
+source_url: https://github.com/anthropics/connect-rust
+description: Generates ConnectRPC service traits, typed clients, and monomorphic dispatchers for Rust. Compatible with the Connect, gRPC, and gRPC-Web protocols. Passes the full ConnectRPC conformance suite.
+deps:
+  - plugin: buf.build/anthropics/buffa:v0.3.0
+output_languages:
+  - rust
+spdx_license_id: Apache-2.0
+license_url: https://github.com/anthropics/connect-rust/blob/v0.3.2/LICENSE
+registry:
+  cargo:
+    rust_version: "1.88"
+    deps:
+      # ConnectRPC runtime: Router, Context, ConnectError, client transports.
+      # https://github.com/anthropics/connect-rust/blob/v0.3.2/connectrpc/Cargo.toml
+      - name: "connectrpc"
+        req: "0.3.2"
+        default_features: true
+      # Generated service stubs use buffa::Message, buffa::view::OwnedView,
+      # buffa::bytes::Bytes directly. Message types live in the buffa SDK
+      # crate (via the plugin dep above); this dep is for the runtime API.
+      - name: "buffa"
+        req: "0.3.0"
+        default_features: true
+      # Streaming method signatures use futures::Stream.
+      - name: "futures"
+        req: "0.3"
+        default_features: true
+      # Client transport bounds reference http_body::Body.
+      - name: "http-body"
+        req: "1"
+        default_features: true
+  # The plugin accepts `extern_path=.=<rust_path>` (or the shorthand
+  # `buffa_module=<rust_path>`) to tell it where the buffa-generated message
+  # types live. BSR should inject this based on the buffa dep's SDK crate
+  # name, same as tonic receives extern_path for its prost dep. Leaving
+  # opts empty here; please advise if an explicit entry is needed.
+  opts: []