Add --no-build switch for invoke local to use already compiled output

Author: Frank Schmid

index.js

@@ -112,9 +112,14 @@ class ServerlessWebpack {
       'before:invoke:local:invoke': () => BbPromise.bind(this)
         .then(() => {
           lib.webpack.isLocal = true;
+          // --no-build override
+          if (this.options.build === false) {
+            this.skipCompile = true;
+          }
+
           return this.serverless.pluginManager.spawn('webpack:validate');
         })
-        .then(() => this.serverless.pluginManager.spawn('webpack:compile'))
+        .then(() => this.skipCompile ? BbPromise.resolve() : this.serverless.pluginManager.spawn('webpack:compile'))
         .then(this.prepareLocalInvoke),
 
       'after:invoke:local:invoke': () => BbPromise.bind(this)
@@ -181,7 +186,7 @@ class ServerlessWebpack {
           lib.webpack.isLocal = true;
         })
         .then(this.prepareStepOfflineInvoke)
-        .then(this.compile)
+        .then(() => this.serverless.pluginManager.spawn('webpack:compile')),
     };
   }
 }

lib/validate.js

@@ -143,6 +143,15 @@ module.exports = {
       this.webpackConfig.output.path = path.join(this.serverless.config.servicePath, this.options.out);
     }
 
+    if (this.skipCompile) {
+      this.serverless.cli.log('Skipping build and using existing compiled output');
+      if (!fse.pathExistsSync(this.webpackConfig.output.path)) {
+        return BbPromise.reject(new this.serverless.classes
+          .Error('No compiled output found'));
+      }
+      this.keepOutputDirectory = true;
+    }
+
     if (!this.keepOutputDirectory) {
       this.options.verbose && this.serverless.cli.log(`Removing ${this.webpackConfig.output.path}`);
       fse.removeSync(this.webpackConfig.output.path);