Add preLoadModules option to import modules on main thread

src/ServerlessOffline.js

@@ -63,6 +63,8 @@ export default class ServerlessOffline {
   async start() {
     this.#mergeOptions()
 
+    this.#preLoadModules()
+
     const {
       albEvents,
       httpEvents,
@@ -417,6 +419,18 @@ export default class ServerlessOffline {
     }
   }
 
+  #preLoadModules() {
+    const { preLoadModules } = this.#options
+    const modules = preLoadModules.split(",")
+    modules.forEach((module) => {
+      try {
+        import(module)
+      } catch (err) {
+        log.error(`Error importing module ${module}: ${err}`)
+      }
+    })
+  }
+
   // TODO FIXME
   // TEMP quick fix to expose for testing, look for better solution
   internals() {
@@ -440,6 +454,10 @@ export default class ServerlessOffline {
       mergeOptions: () => {
         this.#mergeOptions()
       },
+
+      preLoadModules: () => {
+        this.#preLoadModules()
+      },
     }
   }
 }

src/config/commandOptions.js

@@ -135,4 +135,8 @@ export default {
     type: "string",
     usage: "Websocket port to listen on. Default: 3001.",
   },
+  preLoadModules: {
+    type: "string",
+    usage: "A comma separated list of modules to preload on the main thread",
+  },
 }

src/config/defaultOptions.js

@@ -28,4 +28,5 @@ export default {
   webSocketHardTimeout: 7200,
   webSocketIdleTimeout: 600,
   websocketPort: 3001,
+  preLoadModules: '',
 }