feat(packager): ability to run custom scripts after packager install

README.md

@@ -64,6 +64,10 @@ custom:
   esbuild:
     packager: yarn # optional - npm or yarn, default is npm
     packagePath: absolute/path/to/package.json # optional - by default it looks for a package.json in the working directory
+    packagerOptions: # optional - packager related options, currently supports only 'scripts' for both npm and yarn
+      scripts: # scripts to be executed, can be a string or array of strings
+        - echo 'Hello World!'
+        - rm -rf node_modules
 ```
 
 To easily mark all the `dependencies` in `package.json` as `external`, you can utilize `esbuild-node-externals` [plugin](https://www.npmjs.com/package/esbuild-node-externals).

src/index.ts

@@ -27,13 +27,18 @@ export interface WatchConfiguration {
   ignore?: string[] | string;
 }
 
+export interface PackagerOptions {
+  scripts?: string[] | string;
+}
+
 export interface Configuration extends Omit<BuildOptions, 'watch' | 'plugins'> {
   packager: 'npm' | 'yarn';
   packagePath: string;
   exclude: string[];
   watch: WatchConfiguration;
   plugins?: string;
   keepOutputDirectory?: boolean;
+  packagerOptions?: PackagerOptions;
 }
 
 const DEFAULT_BUILD_OPTIONS: Partial<Configuration> = {
@@ -46,7 +51,8 @@ const DEFAULT_BUILD_OPTIONS: Partial<Configuration> = {
     pattern: './**/*.(js|ts)',
     ignore: [WORK_FOLDER, 'dist', 'node_modules', SERVERLESS_FOLDER],
   },
-  keepOutputDirectory: false
+  keepOutputDirectory: false,
+  packagerOptions: {},
 };
 
 export class EsbuildPlugin implements Plugin {
@@ -238,6 +244,7 @@ export class EsbuildPlugin implements Plugin {
         delete config['packagePath'];
         delete config['watch'];
         delete config['keepOutputDirectory'];
+        delete config['packagerOptions'];
 
         const bundlePath = entry.substr(0, entry.lastIndexOf('.')) + '.js';
 

src/pack-externals.ts

@@ -224,6 +224,15 @@ export async function packExternalModules(this: EsbuildPlugin) {
   // Fetch needed original package.json sections
   const sectionNames = packager.copyPackageSectionNames;
 
+  // Get scripts from packager options
+  const packagerScripts = this.buildOptions.packagerOptions
+    ? ([].concat(this.buildOptions.packagerOptions.scripts || []))
+      .reduce((scripts, script, index) => {
+        scripts[`script${index}`] = script;
+        return scripts;
+      }, {})
+    : {};
+
   const rootPackageJson: Record<string, any> = this.serverless.utils.readFileSync(
     rootPackageJsonPath
   );
@@ -267,6 +276,7 @@ export async function packExternalModules(this: EsbuildPlugin) {
       version: '1.0.0',
       description: `Packaged externals for ${this.serverless.service.service}`,
       private: true,
+      scripts: packagerScripts,
     },
     packageSections
   );
@@ -314,4 +324,12 @@ export async function packExternalModules(this: EsbuildPlugin) {
   await packager.prune(compositeModulePath);
   this.options.verbose &&
     this.serverless.cli.log(`Prune: ${compositeModulePath} [${Date.now() - startPrune} ms]`);
+
+  // Run packager scripts
+  if (Object.keys(packagerScripts).length > 0) {
+    const startScripts = Date.now();
+    await packager.runScripts(this.buildDirPath, Object.keys(packagerScripts));
+    this.options.verbose &&
+          this.serverless.cli.log(`Packager scripts took [${Date.now() - startScripts} ms].\nExecuted scripts: ${Object.values(packagerScripts).map(script => `\n  ${script}`)}`);  
+  } 
 }