fix: support typescript in devmode (#12412)

lib/plugins/aws/dev/index.js

@@ -60,6 +60,8 @@ class AwsDev {
 
     await this.update();
 
+    this._updateHooks();
+
     await this.serverless.pluginManager.spawn('deploy');
 
     await this.restore();
@@ -67,6 +69,31 @@ class AwsDev {
     await this.connect();
   }
 
+  /**
+   * When using devmode we are not actually building deploymentArtifacts and are instead
+   * using devmode specific hooks and plugins so we remove all createDeploymentArtifacts
+   * hooks when running dev mode
+   */
+  _updateHooks() {
+    for (const hook of this.serverless.pluginManager.hooks[
+      'after:package:createDeploymentArtifacts'
+    ]) {
+      if (hook.pluginName === 'AwsDev') {
+        continue;
+      }
+      hook.hook = async () => {};
+    }
+
+    for (const hook of this.serverless.pluginManager.hooks[
+      'before:package:createDeploymentArtifacts'
+    ]) {
+      if (hook.pluginName === 'AwsDev') {
+        continue;
+      }
+      hook.hook = async () => {};
+    }
+  }
+
   /**
    * Build, bundle and package the dev mode shim responsible for routing events to the local machine..
    *
@@ -356,7 +383,7 @@ class AwsDev {
     process.on('SIGINT', () => {
       console.log();
       console.log(
-        `Don't forget to run "serverless deploy" to remove dev mode from this stage and region`
+        'Don\'t forget to run "serverless deploy" to remove dev mode from this stage and region'
       );
       process.exit(0);
     });

lib/plugins/aws/dev/local-lambda/index.js

@@ -150,15 +150,30 @@ class LocalLambda {
         context,
       });
 
+      /**
+       * In some scenarios, like using tsx and typescript, you have to provide a PID using
+       * an intermediary logline instead of depending on the spawn process id
+       */
+      let resultPID;
+
       // Spawn a child process to execute the runtime wrapper and set the specified environment variables
-      const child = spawn(runtimeWrapper.command, [runtimeWrapper.path, argsString], {
-        env: this.environment,
-        cwd: this.serviceAbsolutePath,
-      });
+      const child = spawn(
+        runtimeWrapper.command,
+        [...runtimeWrapper.arguments, runtimeWrapper.path, argsString],
+        {
+          env: this.environment,
+          cwd: this.serviceAbsolutePath,
+        }
+      );
 
       // Write standard output
       child.stdout.on('data', (chunk) => {
-        process.stdout.write(chunk.toString());
+        const logLine = chunk.toString();
+        if (logLine.startsWith('RESULT_FILE: ')) {
+          resultPID = logLine.replace('/tmp/sls_', '').replace('.json', '').trim();
+        } else {
+          process.stdout.write(chunk.toString());
+        }
       });
 
       // Write error output
@@ -173,7 +188,7 @@ class LocalLambda {
 
       child.on('close', async (code) => {
         try {
-          const result = await getInvocationResult(child.pid);
+          const result = await getInvocationResult(resultPID ?? child.pid);
 
           resolve(result);
         } catch (error) {
@@ -237,12 +252,14 @@ const fileExists = async (filePath) => {
 const runtimeWrappers = [
   {
     command: 'node',
+    arguments: [],
     path: path.join(__dirname, 'runtime-wrappers/wrapper.js'),
     versions: ['nodejs14.x', 'nodejs16.x', 'nodejs18.x', 'nodejs20.x'],
     extensions: ['.js', '.mjs', '.cjs'],
   },
   {
-    command: 'ts-node',
+    command: 'npx',
+    arguments: ['tsx'],
     path: path.join(__dirname, 'runtime-wrappers/wrapper.ts'),
     versions: ['nodejs14.x', 'nodejs16.x', 'nodejs18.x', 'nodejs20.x'],
     extensions: ['.ts', '.mts', '.cts'],

lib/plugins/aws/dev/local-lambda/runtime-wrappers/wrapper.ts

@@ -107,6 +107,8 @@ const invokeFunction = async (handlerFunction: Function) => {
     // Import and invoke the handler function
     const response = await invokeFunction(await importFunction());
 
+    console.log(`RESULT_FILE: ${path.join(os.tmpdir(), `sls_${process.pid}.json`)}`)
+
     // Save the response for the parent process to fetch and return to Lambda
     saveInvocationResult({ response, error: null });
   } catch (error: any) {

package.json

@@ -76,6 +76,7 @@
     "supports-color": "^8.1.1",
     "tar": "^6.1.15",
     "timers-ext": "^0.1.7",
+    "tsx": "^4.7.2",
     "type": "^2.7.2",
     "untildify": "^4.0.0",
     "uuid": "^9.0.0",