Extension loading support

.github/workflows/test.yml

@@ -42,6 +42,27 @@ jobs:
           done
           echo "sqld is ready!"
 
+      - name: Install sqlean
+        run: |
+          SQLEAN_VERSION=0.27.2
+          case "${{ runner.os }}" in
+            Linux)     OS_SLUG=linux-x86 ;;
+            macOS)     OS_SLUG=macos-x86 ;;
+          esac
+          curl -sL -o sqlean-${OS_SLUG}.zip \
+            https://github.com/nalgeon/sqlean/releases/download/${SQLEAN_VERSION}/sqlean-${OS_SLUG}.zip
+          unzip -q sqlean-${OS_SLUG}.zip -d .
+          echo "$PWD" >> $GITHUB_PATH
+
+      - name: Set extension env
+        run: |
+          case "${{ runner.os }}" in
+            Linux) ext=sqlean.so ;;
+            macOS) ext=sqlean.dylib ;;
+          esac
+          echo "LIBSQL_TEST_EXTENSION=$PWD/$ext" >> $GITHUB_ENV
+          echo "LIBSQL_TEST_EXTENSION_ENTRY=sqlite3_sqlean_init" >> $GITHUB_ENV
+
       - name: Build
         run: go build -v ./...
 

libsql.go

@@ -424,6 +424,20 @@ type conn struct {
 	nativePtr C.libsql_connection_t
 }
 
+func (c *conn) LoadExtension(lib string, entry string) error {
+	libCString := C.CString(lib)
+	defer C.free(unsafe.Pointer(libCString))
+	entryCString := C.CString(entry)
+	defer C.free(unsafe.Pointer(entryCString))
+
+	var errMsg *C.char
+	statusCode := C.libsql_load_extension(c.nativePtr, libCString, entryCString, &errMsg)
+	if statusCode != 0 {
+		return libsqlError(fmt.Sprintf("failed to load extension %s with entry point %s", lib, entry), statusCode, errMsg)
+	}
+	return nil
+}
+
 func (c *conn) Prepare(query string) (sqldriver.Stmt, error) {
 	return c.PrepareContext(context.Background(), query)
 }

libsql_test.go

@@ -1359,3 +1359,71 @@ func TestErrorRowsNext(t *testing.T) {
 		}
 	})
 }
+
+// To run this, set LIBSQL_TEST_EXTENSION to the full path of a valid SQLite extension
+// and (optionally) LIBSQL_TEST_EXTENSION_ENTRY to its init symbol (defaults to "sqlite3_extension_init").
+func TestLoadExtension_Existing(t *testing.T) {
+    extPath := os.Getenv("LIBSQL_TEST_EXTENSION")
+    if extPath == "" {
+        t.Skip("LIBSQL_TEST_EXTENSION not set; skipping existing‐extension load test")
+    }
+    entryPoint := os.Getenv("LIBSQL_TEST_EXTENSION_ENTRY")
+    if entryPoint == "" {
+        entryPoint = "sqlite3_extension_init"
+    }
+
+    db, err := sql.Open("libsql", ":memory:")
+    if err != nil {
+        t.Fatal(err)
+    }
+    defer db.Close()
+
+    ctx := context.Background()
+    sqlConn, err := db.Conn(ctx)
+    if err != nil {
+        t.Fatal(err)
+    }
+    defer sqlConn.Close()
+
+    err = sqlConn.Raw(func(driverConn any) error {
+        cImpl, ok := driverConn.(*conn)
+        if !ok {
+            return fmt.Errorf("unexpected driverConn type %T", driverConn)
+        }
+        return cImpl.LoadExtension(extPath, entryPoint)
+    })
+
+    if err != nil {
+        t.Fatalf("failed to load existing extension %q (entry %q): %v", extPath, entryPoint, err)
+    }
+}
+
+func TestLoadExtension_Nonexistent(t *testing.T) {
+    db, err := sql.Open("libsql", ":memory:")
+    if err != nil {
+        t.Fatal(err)
+    }
+    defer db.Close()
+
+    ctx := context.Background()
+    sqlConn, err := db.Conn(ctx)
+    if err != nil {
+        t.Fatal(err)
+    }
+    defer sqlConn.Close()
+
+    err = sqlConn.Raw(func(driverConn any) error {
+        cImpl, ok := driverConn.(*conn)
+        if !ok {
+            return fmt.Errorf("unexpected driverConn type %T", driverConn)
+        }
+        return cImpl.LoadExtension("nonexistent_extension.so", "entry_point")
+    })
+
+    if err == nil {
+        t.Fatal("expected error loading nonexistent extension, got nil")
+    }
+    if !strings.Contains(err.Error(), "failed to load extension") {
+        t.Fatalf("unexpected error loading extension: %v", err)
+    }
+}