serverless-nextjs · dphang · Oct 20, 2020 · Oct 5, 2020 · Oct 5, 2020 · Oct 5, 2020
diff --git a/documentation/docs/inputs.md b/documentation/docs/inputs.md
@@ -2,20 +2,21 @@
 id: inputs
 title: Inputs
 sidebar_label: Inputs
----     
+---
 
 | Name                     | Type              | Default Value                                                      | Description                                                                                                                                                                                                                                                          |
 | ------------------------ | ----------------- | ------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
 | domain                   | `Array`           | `null`                                                             | For example `['admin', 'portal.com']`                                                                                                                                                                                                                                |
 | bucketName               | `string`          | `null`                                                             | Custom bucket name where static assets are stored. By default is autogenerated.                                            
10000
                                                                                                                                          |
 | bucketRegion             | `string`          | `us-east-1`                                                        | Region where you want to host your s3 bucket. Make sure this is geographically closer to the majority of your end users to reduce latency when CloudFront proxies a request to S3.                                                                                   |
-| nextConfigDir            | `string`          | `./`                                                               | Directory where your application `next.config.js` file is. This input is useful when the `serverless.yml` is not in the same directory as the next app. **Note:** `nextConfigDir` should be set if `next.config.js` `distDir` is used                            |
+| nextConfigDir            | `string`          | `./`                                                               | Directory where your application `next.config.js` file is. This input is useful when the `serverless.yml` is not in the same directory as the next app. **Note:** `nextConfigDir` should be set if `next.config.js` `distDir` is used                                |
 | nextStaticDir            | `string`          | `./`                                                               | If your `static` or `public` directory is not a direct child of `nextConfigDir` this is needed                                                                                                                                                                       |
 | description              | `string`          | `*lambda-type*@Edge for Next CloudFront distribution`              | The description that will be used for both lambdas. Note that "(API)" will be appended to the API lambda description.                                                                                                                                                |
 | policy                   | `string`          | `arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole` | The arn policy that will be assigned to both lambdas.                                                                                                                                                                                                                |
 | runtime                  | `string\|object`  | `nodejs12.x`                                                       | When assigned a value, both the default and api lambdas will be assigned the runtime defined in the value. When assigned to an object, values for the default and api lambdas can be separately defined                                                              |  |
 | memory                   | `number\|object`  | `512`                                                              | When assigned a number, both the default and api lambdas will be assigned memory of that value. When assigned to an object, values for the default and api lambdas can be separately defined                                                                         |  |
 | timeout                  | `number\|object`  | `10`                                                               | Same as above                                                                                                                                                                                                                                                        |
+| handler                  | `string`          | `index.handler`                                                    | When assigned a value, overrides the default function handler to allow for configuration. Copies `handler.js` in route into the Lambda folders. Your handler MUST still call the `default-handler` afterwards or your function won't work with Next.JS               |
 | name                     | `string\|object`  | /                                                                  | When assigned a string, both the default and api lambdas will assigned name of that value. When assigned to an object, values for the default and api lambdas can be separately defined                                                                              |
 | build                    | `boolean\|object` | `true`                                                             | When true builds and deploys app, when false assume the app has been built and uses the `.next` `.serverless_nextjs` directories in `nextConfigDir` to deploy. If an object is passed `build` allows for overriding what script gets called and with what arguments. |
 | build.cmd                | `string`          | `node_modules/.bin/next`                                           | Build command                                                                                                                                                                                                                                                        |
@@ -36,4 +37,4 @@ myNextApp:
   component: serverless-next.js
   inputs:
     bucketName: my-bucket
-```
+```
diff --git a/packages/libs/lambda-at-edge/src/build.ts b/packages/libs/lambda-at-edge/src/build.ts
@@ -35,6 +35,7 @@ type BuildOptions = {
   logLambdaExecutionTimes?: boolean;
   domainRedirects?: { [key: string]: string };
   minifyHandlers?: boolean;
+  handler?: string;
 };
 
 const defaultBuildOptions = {
@@ -258,6 +259,16 @@ class Builder {
         join(this.outputDir, DEFAULT_LAMBDA_CODE_DIR, "index.js"),
         !!this.buildOptions.minifyHandlers
       ),
+      this.buildOptions?.handler
+        ? fse.copy(
+            join(this.nextConfigDir, this.buildOptions.handler),
+            join(
+              this.outputDir,
+              DEFAULT_LAMBDA_CODE_DIR,
+              this.buildOptions.handler
+            )
+          )
+        : Promise.resolve(),
       fse.writeJson(
         join(this.outputDir, DEFAULT_LAMBDA_CODE_DIR, "manifest.json"),
         buildManifest
@@ -338,6 +349,12 @@ class Builder {
         join(this.outputDir, API_LAMBDA_CODE_DIR, "index.js"),
         !!this.buildOptions.minifyHandlers
       ),
+      this.buildOptions?.handler
+        ? fse.copy(
+            join(this.nextConfigDir, this.buildOptions.handler),
+            join(this.outputDir, API_LAMBDA_CODE_DIR, this.buildOptions.handler)
+          )
+        : Promise.resolve(),
       fse.copy(
         join(this.serverlessDir, "pages/api"),
         join(this.outputDir, API_LAMBDA_CODE_DIR, "pages/api")

diff --git a/packages/libs/lambda-at-edge/tests/build/build.test.ts b/packages/libs/lambda-at-edge/tests/build/build.test.ts
@@ -340,4 +340,71 @@ describe("Builder Tests", () => {
       expect(countLines(apiHandler.toString())).toEqual(2);
     });
   });
+
+  describe("Custom handler", () => {
+    let fseRemoveSpy: jest.SpyInstance;
+    let fseEmptyDirSpy: jest.SpyInstance;
+    let defaultBuildManifest: OriginRequestDefaultHandlerManifest;
+    let apiBuildManifest: OriginRequestApiHandlerManifest;
+
+    const fixturePath = join(__dirname, "./simple-app-fixture");
+    const outputDir = join(fixturePath, ".test_sls_next_output");
+
+    beforeEach(async () => {
+      const mockExeca = execa as jest.Mock;
+      mockExeca.mockResolvedValueOnce();
+
+      fseRemoveSpy = jest
+        .spyOn(fse, "remove")
+        .mockImplementation(() => undefined);
+      fseEmptyDirSpy = jest.spyOn(fse, "emptyDir");
+      const builder = new Builder(fixturePath, outputDir, {
+        handler: "testFile.js"
+      });
+      await builder.build();
+
+      defaultBuildManifest = await fse.readJSON(
+        join(outputDir, `${DEFAULT_LAMBDA_CODE_DIR}/manifest.json`)
+      );
+
+      apiBuildManifest = await fse.readJSON(
+        join(outputDir, `${API_LAMBDA_CODE_DIR}/manifest.json`)
+      );
+    });
+
+    afterEach(() => {
+      fseEmptyDirSpy.mockRestore();
+      fseRemoveSpy.mockRestore();
+      return cleanupDir(outputDir);
+    });
+
+    it("copies build files", async () => {
+      expect.assertions(2);
+
+      const defaultFiles = await fse.readdir(
+        join(outputDir, `${DEFAULT_LAMBDA_CODE_DIR}`)
+      );
+
+      expect(defaultFiles).toEqual([
+        "index.js",
+        "manifest.json",
+        "pages",
+        "prerender-manifest.json",
+        "routes-manifest.json",
+        "testFile.js"
+      ]);
+
+      const apiFiles = await fse.readdir(
+        join(outputDir, `${API_LAMBDA_CODE_DIR}`)
+      );
+
+      expect(apiFiles).toEqual([
+        "index.js",
+        "manifest.json",
+        "pages",
+        "routes-manifest.json",
+        "testFile.js"
+      ]);
+    });
+  });
 });
diff --git a/packages/libs/lambda-at-edge/tests/build/simple-app-fixture/testFile.js b/packages/libs/lambda-at-edge/tests/build/simple-app-fixture/testFile.js
@@ -0,0 +1 @@
+// Test handler file to check if copied
diff --git a/packages/serverless-components/nextjs-component/__tests__/custom-inputs.test.ts b/packages/serverless-components/nextjs-component/__tests__/custom-inputs.test.ts
@@ -1011,4 +1011,43 @@ describe("Custom inputs", () => {
       });
     });
   });
+
+  describe.each([
+    [undefined, "index.handler"],
+    ["customHandler.handler", "customHandler.handler"]
+  ])("Lambda handler input", (inputHandler, expectedHandler) => {
+    const fixturePath = path.join(__dirname, "./fixtures/generic-fixture");
+    let tmpCwd;
+
+    beforeEach(async () => {
+      tmpCwd = process.cwd();
+      process.chdir(fixturePath);
+      mockServerlessComponentDependencies({});
+      const component = createNextComponent({ handler: inputHandler });
+      componentOutputs = await component({ handler: inputHandler });
+    });
+
+    afterEach(() => {
+      process.chdir(tmpCwd);
+      return cleanupFixtureDirectory(fixturePath);
+    });
+
+    it(`sets handler to ${expectedHandler} and api lambda handler to ${expectedHandler}`, () => {
+      // default Lambda
+      expect(mockLambda).toBeCalledWith(
+        expect.objectContaining({
+          code: path.join(fixturePath, DEFAULT_LAMBDA_CODE_DIR),
+          handler: expectedHandler
+        })
+      );
+
+      // api Lambda
      expect(mockLambda).toBeCalledWith(
+        expect.objectContaining({
+          code: path.join(fixturePath, API_LAMBDA_CODE_DIR),
+          handler: expectedHandler
+        })
+      );
+    });
+  });
 });
diff --git a/...erverless-components/nextjs-component/__tests__/fixtures/generic-fixture/customHandler.js b/...erverless-components/nextjs-component/__tests__/fixtures/generic-fixture/customHandler.js
@@ -0,0 +1 @@
+// Test custom handler to be copied
diff --git a/packages/serverless-components/nextjs-component/src/component.ts b/packages/serverless-components/nextjs-component/src/component.ts
@@ -197,7 +197,10 @@ class NextjsComponent extends Component {
           useServerlessTraceTarget: inputs.useServerlessTraceTarget || false,
           logLambdaExecutionTimes: inputs.logLambdaExecutionTimes || false,
           domainRedirects: inputs.domainRedirects || {},
-          minifyHandlers: inputs.minifyHandlers || false
+          minifyHandlers: inputs.minifyHandlers || false,
+          handler: inputs.handler
+            ? `${inputs.handler.split(".")[0]}.js`
+            : undefined
         },
         nextStaticPath
       );
@@ -408,7 +411,7 @@ class NextjsComponent extends Component {
         description: inputs.description
           ? `${inputs.description} (API)`
           : "API Lambda@Edge for Next CloudFront distribution",
-        handler: "index.handler",
+        handler: inputs.handler || "index.handler",
         code: join(nextConfigPath, API_LAMBDA_CODE_DIR),
         role: {
           service: ["lambda.amazonaws.com", "edgelambda.amazonaws.com"],
@@ -456,7 +459,7 @@ class NextjsComponent extends Component {
       description:
         inputs.description ||
         "Default Lambda@Edge for Next CloudFront distribution",
-      handler: "index.handler",
+      handler: inputs.handler || "index.handler",
       code: join(nextConfigPath, DEFAULT_LAMBDA_CODE_DIR),
       role: {
         service: ["lambda.amazonaws.com", "edgelambda.amazonaws.com"],

diff --git a/packages/serverless-components/nextjs-component/types.d.ts b/packages/serverless-components/nextjs-component/types.d.ts
@@ -13,6 +13,7 @@ export type ServerlessComponentInputs = {
   timeout?: number | { defaultLambda?: number; apiLambda?: number };
   name?: string | { defaultLambda?: string; apiLambda?: string };
   runtime?: string | { defaultLambda?: string; apiLambda?: string };
+  handler?: string;
   description?: string;
   policy?: string;
   domain?: string | string[];