feat: keep Rust telemetry aligned with registry conventions

.config/mise/tasks/weaver/test/_default

@@ -1,3 +1,3 @@
 #!/usr/bin/env bash
-#MISE description="Run every policy and template package test, and compile the generated Go"
-#MISE depends=["weaver:test:policies", "weaver:test:templates", "weaver:test:go"]
+#MISE description="Run every policy and template package test, and validate generated Go and Rust"
+#MISE depends=["weaver:test:policies", "weaver:test:templates", "weaver:test:go", "weaver:test:rust"]

.config/mise/tasks/weaver/test/rust

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+#MISE description="Check that generated Rust is formatted, tested, and passes Clippy"
+set -euo pipefail
+exec ./buildscripts/check_rust_output.sh

.github/workflows/checks.yml

@@ -38,6 +38,7 @@ jobs:
       - uses: jdx/mise-action@c2a87611a18de5b3828c5652fe268e992400cb5c # v4.3.0
       - run: mise run weaver:test:templates
       - run: mise run weaver:test:go
+      - run: mise run weaver:test:rust
 
   markdown:
     name: Markdown

AGENTS.md

@@ -38,6 +38,10 @@ Each template package includes:
 Generated Go must pass `gofmt`, `go build`, and `go vet`, which
 `mise run weaver:test:go` checks.
 
+Generated Rust must pass formatting, consumer tests, and Clippy, which
+`mise run weaver:test:rust` checks against the pinned OpenTelemetry Rust API
+and SDK.
+
 ## Contribution guidelines
 
 - Keep changes to the package being modified.

CONTRIBUTING.md

@@ -55,6 +55,11 @@ Run `mise tasks` to list every task and what it does.
 Every test must pass before a pull request is merged. The `Checks` workflow
 runs the same tasks.
 
+For Rust packages, `mise run weaver:test:rust` compiles the expected output in
+temporary crates and runs formatting, consumer tests, and Clippy. Put consumer
+tests in a case's `test.rs`, importing the generated crate as
+`generated_semconv`.
+
 Keep test registries synthetic. Use neutral namespaces such as `myapp` and
 `auth` rather than conventions from a real system.
 

README.md

@@ -6,7 +6,8 @@ is versioned and released from this repository, ready to be referenced by tag.
 
 **The packages turn a semantic convention registry into code and keep that
 registry fit for generation.** Templates generate typed telemetry helpers, such
-as Go attribute values and metric instruments on the OpenTelemetry Go API.
+as typed attribute values and signal helpers on the OpenTelemetry Go and
+Rust APIs.
 Policies run during `weaver registry check` and reject conventions a template
 cannot render, before any code is written.
 
@@ -29,6 +30,9 @@ Templates live under [`templates`](templates) and policies under
 [`policies`](policies). Each package directory has a README describing what it
 does and the params it accepts.
 
+- [Go code generation](templates/code/go/README.md)
+- [Rust code generation](templates/code/rust/README.md)
+
 ## Using a package
 
 Weaver accepts a Git repository as a template or policy location, in the form

buildscripts/check_rust_output.sh

@@ -0,0 +1,115 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+OTEL_RUST_VERSION="${OTEL_RUST_VERSION:-0.33.0}"
+WEAVER="${WEAVER:-weaver}"
+ROOT="$(pwd)"
+PACKAGE_DIR="${ROOT}/templates/code/rust"
+TEMPLATES_ROOT="$(realpath "${PACKAGE_DIR}/../..")"
+
+WORK_DIR="$(mktemp -d "${TMPDIR:-/tmp}/weaver-rust.XXXXXX")"
+trap 'rm -rf "${WORK_DIR}"' EXIT
+export CARGO_TARGET_DIR="${CARGO_TARGET_DIR:-${WORK_DIR}/target}"
+
+for test_dir in "${PACKAGE_DIR}"/tests/*/; do
+  test_name="$(basename "${test_dir}")"
+  [[ -f "${test_dir}expected-error.txt" ]] && continue
+  expected="${test_dir}expected"
+  if [[ ! -f "${expected}/mod.rs" ]]; then
+    echo "  FAIL: ${test_name} is missing expected/mod.rs."
+    exit 1
+  fi
+  echo "-> Checking Rust [${test_name}] ..."
+
+  crate_dir="${WORK_DIR}/${test_name}"
+  mkdir -p "${crate_dir}/src"
+  cp -R "${expected}/." "${crate_dir}/src/"
+  mv "${crate_dir}/src/mod.rs" "${crate_dir}/src/lib.rs"
+  if [[ -f "${test_dir}test.rs" ]]; then
+    mkdir -p "${crate_dir}/tests"
+    cp "${test_dir}test.rs" "${crate_dir}/tests/attributes.rs"
+  fi
+  if [[ -d "${test_dir}tests" ]]; then
+    mkdir -p "${crate_dir}/tests"
+    cp -R "${test_dir}tests/." "${crate_dir}/tests/"
+  fi
+
+  cat >"${crate_dir}/Cargo.toml" <<EOF
+[package]
+name = "generated_semconv"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[dependencies]
+opentelemetry = { version = "=${OTEL_RUST_VERSION}", features = ["logs", "metrics", "trace"] }
+opentelemetry_sdk = { version = "=${OTEL_RUST_VERSION}", features = ["logs", "metrics", "trace", "testing"] }
+smallvec = { version = "=1.16.2", features = ["const_generics"] }
+EOF
+
+  if [[ -f "${test_dir}dependency-params.yaml" ]]; then
+    dependency_dir="${crate_dir}/upstream"
+    mkdir -p "${dependency_dir}/src"
+    (
+      cd "${test_dir}"
+      NO_COLOR=1 "${WEAVER}" registry generate -r dependency --v2 --quiet \
+        --params dependency-params.yaml --templates="${TEMPLATES_ROOT}" \
+        code/rust "${dependency_dir}/src"
+    ) || { echo "  FAIL: ${test_name} could not generate its dependency."; exit 1; }
+    mv "${dependency_dir}/src/mod.rs" "${dependency_dir}/src/lib.rs"
+    cat >"${dependency_dir}/Cargo.toml" <<EOF
+[package]
+name = "upstream"
+version = "0.0.0"
+edition = "2021"
+publish = false
+
+[dependencies]
+opentelemetry = "=${OTEL_RUST_VERSION}"
+opentelemetry_sdk = "=${OTEL_RUST_VERSION}"
+smallvec = { version = "=1.16.2", features = ["const_generics"] }
+EOF
+    printf '\nupstream = { path = "upstream" }\n' >>"${crate_dir}/Cargo.toml"
+    (
+      cd "${dependency_dir}"
+      cargo fmt --all || exit 1
+      cargo fmt --all --check || exit 1
+      cargo clippy --all-targets -- -D warnings || exit 1
+    ) || { echo "  FAIL: ${test_name} dependency fails Rust validation."; exit 1; }
+  fi
+
+  (
+    cd "${crate_dir}"
+    cargo fmt --all || exit 1
+    cargo fmt --all --check || exit 1
+    if [[ "${test_name}" == allocations || -f "${test_dir}tests/allocations.rs" ]]; then
+      cargo test --release -- --nocapture || exit 1
+    else
+      cargo test || exit 1
+    fi
+    cargo clippy --all-targets -- -D warnings || exit 1
+    for invalid_consumer in "${test_dir}"compile-fail/*.rs; do
+      [[ -f "${invalid_consumer}" ]] || continue
+      expected_error="${invalid_consumer%.rs}.expected-error.txt"
+      if [[ ! -s "${expected_error}" ]]; then
+        echo "  FAIL: ${invalid_consumer} is missing its expected diagnostic."
+        exit 1
+      fi
+      mkdir -p examples
+      cp "${invalid_consumer}" examples/invalid_consumer.rs
+      if cargo check --example invalid_consumer >diagnostics.txt 2>&1; then
+        echo "  FAIL: ${invalid_consumer} compiled successfully."
+        exit 1
+      fi
+      if ! grep -Fq -f "${expected_error}" diagnostics.txt; then
+        cat diagnostics.txt
+        echo "  FAIL: ${invalid_consumer} did not fail with its expected diagnostic."
+        exit 1
+      fi
+      rm examples/invalid_consumer.rs
+      echo "  PASS: $(basename "${invalid_consumer}") rejects its invalid consumer."
+    done
+  ) || { echo "  FAIL: ${test_name} does not pass Rust validation."; exit 1; }
+  echo "  PASS: ${test_name} formats, tests, and passes Clippy."
+done

mise.toml

@@ -3,4 +3,5 @@
 go = "1.27.1"
 jq = "1.8.1"
 node = "24.21.0"
+rust = { version = "1.99.0", profile = "minimal", components = ["rustfmt", "clippy"] }
 "npm:prettier" = "3.9.9"