Merge pull request #323 from tinchoz49/tinchoz49/add-config-hook

feat: add support for config file

README.md

@@ -133,6 +133,26 @@ _Note:_ If you are using Python functions with Serverless Offline you will need
 
 ## Advanced Configuration
 
+### Config file
+
+Esbuild configuration can be defined by a config file.
+
+```yml
+custom:
+  esbuild:
+    config: './esbuild.config.js'
+```
+
+```js
+// esbuild.config.js
+module.exports = (serverless) => ({
+  external: [
+    'lodash'
+  ],
+  plugins: []
+})
+```
+
 ### Including Extra Files
 
 [Serverless Package Configuration](https://www.serverless.com/framework/docs/providers/aws/guide/packaging#package-configuration) will behave in the same way as native packaging. You can use `patterns`, `include` and `exclude` to include extra files into your bundles.

examples/config/config.js

@@ -0,0 +1,23 @@
+module.exports = () => {
+  return {
+    packager: 'npm',
+    bundle: true,
+    minify: true,
+    sourcemap: false,
+    keepNames: true,
+    external: [
+      'lodash'
+    ],
+    plugins: [
+      {
+        name: 'log-lodash',
+        setup(build) {
+          // test interception : log all lodash imports
+          build.onResolve({ filter: /^lodash$/ }, args => {
+            console.log(args);
+          });
+        },
+      }
+    ]
+  };
+};

examples/config/hello1.ts

@@ -0,0 +1,20 @@
+import * as _ from 'lodash';
+
+// modern module syntax
+export async function handler(event, context, callback) {
+  // dependencies work as expected
+  console.log(_.VERSION);
+
+  // async/await also works out of the box
+  await new Promise((resolve) => setTimeout(resolve, 500));
+
+  const response = {
+    statusCode: 200,
+    body: JSON.stringify({
+      message: 'Go Serverless v1.0! Your function executed successfully!',
+      input: event,
+    }),
+  };
+
+  callback(null, response);
+}

examples/config/hello2.ts

@@ -0,0 +1,15 @@
+// modern module syntax
+export async function handler(event, context, callback) {
+  // async/await also works out of the box
+  await new Promise((resolve) => setTimeout(resolve, 500));
+
+  const response = {
+    statusCode: 200,
+    body: JSON.stringify({
+      message: 'Go Serverless v1.0! Your function executed successfully!',
+      input: event,
+    }),
+  };
+
+  callback(null, response);
+}