DuckDB test to ensure FFI doesn't crash on simple query (#7147)

* test_duckdb_ffi

* build dev duckdb lib

* cache

.github/workflows/backend-test.yml

@@ -67,13 +67,21 @@ jobs:
       - name: Substitute EE code (EE logic is behind feature flag)
         run: |
           ./substitute_ee_code.sh --copy --dir ./windmill-ee-private
+      - name: Cache DuckDB FFI module build
+        uses: actions/cache@v3
+        with:
+          path: ./backend/windmill-duckdb-ffi-internal/target
+          key: ${{ runner.os }}-duckdb-ffi-${{ hashFiles('./backend/windmill-duckdb-ffi-internal/src/**/*.rs', './backend/windmill-duckdb-ffi-internal/Cargo.toml', './backend/windmill-duckdb-ffi-internal/Cargo.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-duckdb-ffi-
       - name: cargo test
         timeout-minutes: 16
         run: deno --version && bun -v && go version && python3 --version &&
+          cd windmill-duckdb-ffi-internal && ./build_dev.sh && cd .. &&
           SQLX_OFFLINE=true
           DATABASE_URL=postgres://postgres:changeme@localhost:5432/windmill
           DISABLE_EMBEDDING=true RUST_LOG=info RUST_LOG_STYLE=never
           DENO_PATH=$(which deno) BUN_PATH=$(which bun) GO_PATH=$(which go)
           UV_PATH=$(which uv) cargo test --features
-          enterprise,deno_core,license,python,rust,scoped_cache,private --all --
+          enterprise,deno_core,license,python,duckdb,rust,scoped_cache,private --all --
           --nocapture

backend/run_until_fail.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 # Run the command repeatedly until it fails (exits with non-zero code)
+cd windmill-duckdb-ffi-internal && ./build_dev.sh && cd ..
 while true; do
     DISABLE_EMBEDDING=true \
     RUST_LOG=info \
@@ -9,7 +10,7 @@ while true; do
     GO_PATH=$(which go) \
     UV_PATH=$(which uv) \
     CARGO_PATH=$(which cargo) \
-    cargo test --features enterprise,deno_core,license,python,rust,scoped_cache \
+    cargo test --features enterprise,deno_core,license,python,duckdb,rust,scoped_cache \
         -- --nocapture --test-threads=8 | tee /tmp/test.log
     
     # Capture the exit code of the cargo test command (not tee)

backend/tests/worker.rs

@@ -2944,3 +2944,33 @@ async fn test_workflow_as_code(db: Pool<Postgres>) -> anyhow::Result<()> {
     .await;
     Ok(())
 }
+
+#[cfg(feature = "duckdb")]
+#[sqlx::test(fixtures("base"))]
+async fn test_duckdb_ffi(db: Pool<Postgres>) -> anyhow::Result<()> {
+    initialize_tracing().await;
+
+    let server = ApiServer::start(db.clone()).await?;
+
+    let content = "-- result_collection=last_statement_first_row_scalar\nSELECT 'Hello world!';";
+
+    let flow: FlowValue = serde_json::from_value(serde_json::json!({
+        "modules": [{
+            "value": {
+                "type": "rawscript",
+                "language": "duckdb",
+                "content": content,
+            },
+        }],
+    }))
+    .unwrap();
+
+    let result =
+        RunJob::from(JobPayload::RawFlow { value: flow.clone(), path: None, restarted_from: None })
+            .run_until_complete(&db, false, server.addr.port())
+            .await
+            .json_result()
+            .unwrap();
+    assert_eq!(result, serde_json::json!("Hello world!"));
+    Ok(())
+}