Run tests and lint for Rust code in CI. (#1289)

Run tools like `clippy`, `cargo fmt`, `cargo doc`, and tests over our
Rust code in CI.

.github/workflows/rust_test.yml

@@ -0,0 +1,114 @@
+name: Run Rust CI
+
+# Our Rust code depends on the vendored `orjson` and `pyo3` workspaces,
+# so ensure that CI re-runs if they are modified.
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "rust/**"
+      - "vendor/orjson/**"
+      - "vendor/pyo3/**"
+      - ".github/workflows/rust_test.yml"
+  pull_request:
+    paths:
+      - "rust/**"
+      - "vendor/orjson/**"
+      - "vendor/pyo3/**"
+      - ".github/workflows/rust_test.yml"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+env:
+  RUST_VERSION: '1.82'  # Be careful, "stable" gets you "whatever GitHub ships", which is quite old.
+  RUST_WORKSPACE_PATH: 'rust'  # The location of the Rust workspace relative to the repo root.
+
+jobs:
+  lint:
+    name: Check lint and rustfmt
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Install rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          toolchain: "${{env.RUST_VERSION}}"
+          components: rustfmt, clippy
+          cache-workspaces: "${{env.RUST_WORKSPACE_PATH}} -> target"
+          rustflags: ""
+
+      - name: cargo clippy
+        working-directory: ${{env.RUST_WORKSPACE_PATH}}
+        run: cargo clippy --workspace --all-targets --all-features --no-deps -- -D warnings --allow deprecated
+
+      - name: cargo fmt
+        working-directory: ${{env.RUST_WORKSPACE_PATH}}
+        run: cargo fmt -- --check
+
+      - name: cargo doc
+        working-directory: ${{env.RUST_WORKSPACE_PATH}}
+        env:
+          RUSTDOCFLAGS: -D warnings
+        run: cargo doc --workspace --no-deps --document-private-items
+  cargo-test:
+    name: Run `cargo test`
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Install rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          toolchain: "${{env.RUST_VERSION}}"
+          cache-workspaces: "${{env.RUST_WORKSPACE_PATH}} -> target"
+          rustflags: ""
+
+      - name: cargo test
+        working-directory: ${{env.RUST_WORKSPACE_PATH}}
+        run: |
+          set -euxo pipefail
+
+          # We exclude `langsmith-pyo3` since its tests:
+          # - Have to be run under `nextest`, since they require one-process-per-test.
+          # - Require a non-default configuration in order to run.
+          cargo test --workspace --exclude langsmith-pyo3 --all-features
+
+  langsmith-pyo3-tests:
+    name: Run langsmith-pyo3 tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+
+      - name: Install rust
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          toolchain: "${{env.RUST_VERSION}}"
+          cache-workspaces: "${{env.RUST_WORKSPACE_PATH}} -> target"
+          rustflags: ""
+
+      - name: Install cargo-nextest
+        uses: taiki-e/install-action@v2
+        with:
+          tool: cargo-nextest
+
+      - name: cargo test
+        working-directory: "${{env.RUST_WORKSPACE_PATH}}/crates/langsmith-pyo3"
+        run: |
+          set -euxo pipefail
+
+          # See the langsmith-pyo3 README.md file for an explanation
+          # of why tests have to run under nextest & without default features.
+          cargo nextest run --no-default-features

rust/crates/langsmith-pyo3/src/py_run.rs

@@ -118,10 +118,13 @@ impl FromPyObject<'_> for RunCreate {
 
         let run_type =
             value.get_item(pyo3::intern!(value.py(), "run_type"))?.extract::<String>()?;
-        let reference_example_id = extract_string_like_or_none(get_optional_value_from_mapping(
-            value,
-            pyo3::intern!(value.py(), "reference_example_id"),
-        ).as_ref())?;
+        let reference_example_id = extract_string_like_or_none(
+            get_optional_value_from_mapping(
+                value,
+                pyo3::intern!(value.py(), "reference_example_id"),
+            )
+            .as_ref(),
+        )?;
 
         Ok(Self(langsmith_tracing_client::client::RunCreate {
             common,
@@ -151,32 +154,31 @@ impl FromPyObject<'_> for RunCommon {
             extract_string_like(&value.get_item(pyo3::intern!(value.py(), "trace_id"))?)?;
 
         let dotted_order = value.get_item(pyo3::intern!(value.py(), "dotted_order"))?.extract()?;
-        let parent_run_id = extract_string_like_or_none(get_optional_value_from_mapping(
-            value,
-            pyo3::intern!(value.py(), "parent_run_id"),
-        ).as_ref())?;
+        let parent_run_id = extract_string_like_or_none(
+            get_optional_value_from_mapping(value, pyo3::intern!(value.py(), "parent_run_id"))
+                .as_ref(),
+        )?;
 
         let extra = extract_optional_value_from_mapping(value, pyo3::intern!(value.py(), "extra"))?;
 
-        let error = extract_string_like_or_none(get_optional_value_from_mapping(
-            value,
-            pyo3::intern!(value.py(), "error"),
-        ).as_ref())?;
+        let error = extract_string_like_or_none(
+            get_optional_value_from_mapping(value, pyo3::intern!(value.py(), "error")).as_ref(),
+        )?;
 
         let serialized =
             extract_optional_value_from_mapping(value, pyo3::intern!(value.py(), "serialized"))?;
         let events =
             extract_optional_value_from_mapping(value, pyo3::intern!(value.py(), "events"))?;
         let tags = extract_optional_value_from_mapping(value, pyo3::intern!(value.py(), "tags"))?;
 
-        let session_id = extract_string_like_or_none(get_optional_value_from_mapping(
-            value,
-            pyo3::intern!(value.py(), "session_id"),
-        ).as_ref())?;
-        let session_name = extract_string_like_or_none(get_optional_value_from_mapping(
-            value,
-            pyo3::intern!(value.py(), "session_name"),
-        ).as_ref())?;
+        let session_id = extract_string_like_or_none(
+            get_optional_value_from_mapping(value, pyo3::intern!(value.py(), "session_id"))
+                .as_ref(),
+        )?;
+        let session_name = extract_string_like_or_none(
+            get_optional_value_from_mapping(value, pyo3::intern!(value.py(), "session_name"))
+                .as_ref(),
+        )?;
 
         Ok(Self(langsmith_tracing_client::client::RunCommon {
             id,

rust/crates/langsmith-tracing-client/benches/json_serialization_benchmark.rs

@@ -93,7 +93,9 @@ fn benchmark_gzip_only_parallel(data: &Vec<Vec<u8>>) -> Vec<Vec<u8>> {
 
 // into par iter
 fn benchmark_json_only_parallel(data: &[Value]) -> Vec<Vec<u8>> {
-    data.par_iter().map(|json| serde_json::to_vec(json).expect("Failed to serialize JSON")).collect()
+    data.par_iter()
+        .map(|json| serde_json::to_vec(json).expect("Failed to serialize JSON"))
+        .collect()
 }
 
 fn json_benchmark_large_array(c: &mut Criterion) {