feat: Add Lambda+ApiGateway+Codepipeline example. Fixes #267

This commit adds an example that deploys a Lambda+ApiGateway setup using CodePipeline.
Although there's plenty of examples of Lambda already, deploying them via CodePipeline had some non-trivial challenges to sort out. This could mean teams start using CDK and like it, but drop it because they can't adopt Full CI/CD easily when using it

.gitignore

@@ -233,7 +233,6 @@ dist/
 downloads/
 eggs/
 .eggs/
-lib/
 lib64/
 parts/
 sdist/

typescript/lambda-api-ci/.gitignore

@@ -0,0 +1,9 @@
+*.js
+!jest.config.js
+*.d.ts
+node_modules
+
+# CDK asset staging directory
+.cdk.staging
+cdk.out
+*.iml

typescript/lambda-api-ci/.npmignore

@@ -0,0 +1,6 @@
+*.ts
+!*.d.ts
+
+# CDK asset staging directory
+.cdk.staging
+cdk.out

typescript/lambda-api-ci/.prettierrc

@@ -0,0 +1,5 @@
+{
+  "printWidth": 100,
+  "semi": false,
+  "tabWidth": 4
+}

typescript/lambda-api-ci/README.md

@@ -0,0 +1,15 @@
+# What's this?
+This is code sample that uses CDK to:
+* Create a Lambda function that can be invoked using API Gateway
+* Create a CI using CodeSuite that deploys the Lambda+ApiGateway resources using `cdk deploy`
+
+# How do I start using it?
+* Ensure you've followed the [guide to Getting Started to AWS CDK](https://docs.aws.amazon.com/cdk/latest/guide/getting_started.html), and you have CDK installed, and the AWS SDK installed and credentials configured. 
+* [Bootstrap your AWS environment](https://docs.aws.amazon.com/cdk/latest/guide/serverless_example.html#serverless_example_deploy_and_test)
+* Create a CodeCommit repository. See [this documentation](https://docs.aws.amazon.com/codecommit/latest/userguide/how-to-create-repository.html) for help.
+* Place the contents of this folder inside it
+* Set the repository name in the `repositoryName` prop in `bin/ci.ts`.
+* Build the stack with `npm run build`
+* Deploy the CI stack with `cdk deploy`
+* `Todo` summarize permissions
+    * If you'd like to deploy just the Lambda+ApiGateway stack, you can do so with `cdk deploy -a "npx ts-node bin/lambda.ts"`

typescript/lambda-api-ci/bin/ci.ts

@@ -0,0 +1,9 @@
+#!/usr/bin/env node
+import "source-map-support/register"
+import cdk = require("@aws-cdk/core")
+import { CIStack } from "../lib/ci-stack"
+
+const app = new cdk.App()
+new CIStack(app, "CDKExampleLambdaApiCIStack", {
+    repositoryName: "lambda-api-ci",
+})

typescript/lambda-api-ci/bin/lambda.ts

@@ -0,0 +1,12 @@
+#!/usr/bin/env node
+import "source-map-support/register"
+import cdk = require("@aws-cdk/core")
+import { CDKExampleLambdaApiStack } from "../lib/lambda-api-stack"
+
+export const lambdaApiStackName = "CDKExampleLambdaApiStack"
+export const lambdaFunctionName = "CDKExampleWidgetStoreFunction"
+
+const app = new cdk.App()
+new CDKExampleLambdaApiStack(app, lambdaApiStackName, {
+    functionName: lambdaFunctionName,
+})

typescript/lambda-api-ci/buildspec.yml

@@ -0,0 +1,17 @@
+
+version: 0.2
+
+phases:
+  install:
+    runtime-versions:
+      nodejs: 12
+    commands:
+      - npm install
+
+  build:
+    commands:
+      - npm run build
+      - npm run -- cdk deploy --ci --require-approval never -a "npx ts-node bin/lambda.ts"
+artifacts:
+  files:
+    - "cdk.out/**/*"

typescript/lambda-api-ci/cdk.json

@@ -0,0 +1,3 @@
+{
+  "app": "npx ts-node bin/ci.ts"
+}

typescript/lambda-api-ci/jest.config.js

@@ -0,0 +1,9 @@
+module.exports = {
+    "roots": [
+      "<rootDir>/test"
+    ],
+    testMatch: [ '**/*.test.ts'],
+    "transform": {
+      "^.+\\.tsx?$": "ts-jest"
+    },
+  }

typescript/lambda-api-ci/lib/ci-stack.ts

@@ -0,0 +1,118 @@
+import { CodeCommitSourceAction, CodeBuildAction } from "@aws-cdk/aws-codepipeline-actions"
+import { PolicyStatement } from "@aws-cdk/aws-iam"
+import { Construct, Stack, StackProps } from "@aws-cdk/core"
+import { PipelineProject, LinuxBuildImage } from "@aws-cdk/aws-codebuild"
+import { Artifact, Pipeline } from "@aws-cdk/aws-codepipeline"
+import { Repository } from "@aws-cdk/aws-codecommit"
+import { lambdaApiStackName, lambdaFunctionName } from "../bin/lambda"
+
+interface CIStackProps extends StackProps {
+    repositoryName: string
+}
+
+export class CIStack extends Stack {
+    constructor(scope: Construct, name: string, props: CIStackProps) {
+        super(scope, name, props)
+
+        const pipeline = new Pipeline(this, "Pipeline", {})
+
+        const repo = Repository.fromRepositoryName(
+            this,
+            "WidgetsServiceRepository",
+            props.repositoryName
+        )
+        const sourceOutput = new Artifact("SourceOutput")
+        const sourceAction = new CodeCommitSourceAction({
+            actionName: "CodeCommit",
+            repository: repo,
+            output: sourceOutput,
+        })
+        pipeline.addStage({
+            stageName: "Source",
+            actions: [sourceAction],
+        })
+
+        this.createBuildStage(pipeline, sourceOutput)
+    }
+
+    private createBuildStage(pipeline: Pipeline, sourceOutput: Artifact) {
+        const project = new PipelineProject(this, `BuildProject`, {
+            environment: {
+                buildImage: LinuxBuildImage.STANDARD_3_0,
+            },
+        })
+
+        const cdkDeployPolicy = new PolicyStatement()
+        cdkDeployPolicy.addActions(
+            "cloudformation:GetTemplate",
+            "cloudformation:CreateChangeSet",
+            "cloudformation:DescribeChangeSet",
+            "cloudformation:ExecuteChangeSet",
+            "cloudformation:DescribeStackEvents",
+            "cloudformation:DeleteChangeSet",
+            "cloudformation:DescribeStacks",
+            "s3:*Object",
+            "s3:ListBucket",
+            "s3:getBucketLocation",
+            "lambda:UpdateFunctionCode",
+            "lambda:GetFunction",
+            "lambda:CreateFunction",
+            "lambda:DeleteFunction",
+            "lambda:GetFunctionConfiguration",
+            "lambda:AddPermission",
+            "lambda:RemovePermission"
+        )
+        cdkDeployPolicy.addResources(
+            this.formatArn({
+                service: "cloudformation",
+                resource: "stack",
+                resourceName: "CDKToolkit/*",
+            }),
+            this.formatArn({
+                service: "cloudformation",
+                resource: "stack",
+                resourceName: `${lambdaApiStackName}/*`,
+            }),
+            this.formatArn({
+                service: "lambda",
+                resource: "function",
+                sep: ":",
+                resourceName: lambdaFunctionName,
+            }),
+            "arn:aws:s3:::cdktoolkit-stagingbucket-*"
+        )
+        const editOrCreateLambdaDependencies = new PolicyStatement()
+        editOrCreateLambdaDependencies.addActions(
+            "iam:GetRole",
+            "iam:PassRole",
+            "iam:CreateRole",
+            "iam:AttachRolePolicy",
+            "iam:PutRolePolicy",
+            "apigateway:GET",
+            "apigateway:DELETE",
+            "apigateway:PUT",
+            "apigateway:POST",
+            "apigateway:PATCH",
+            "s3:CreateBucket",
+            "s3:PutBucketTagging"
+        )
+        editOrCreateLambdaDependencies.addResources("*")
+        project.addToRolePolicy(cdkDeployPolicy)
+        project.addToRolePolicy(editOrCreateLambdaDependencies)
+
+        const buildOutput = new Artifact(`BuildOutput`)
+        const buildAction = new CodeBuildAction({
+            actionName: `Build`,
+            project,
+            input: sourceOutput,
+            outputs: [buildOutput],
+        })
+
+        pipeline.addStage({
+            stageName: "build",
+            actions: [buildAction],
+        })
+
+        return buildOutput
+    }
+}

typescript/lambda-api-ci/lib/lambda-api-stack.ts

@@ -0,0 +1,49 @@
+import { LambdaIntegration, MethodLoggingLevel, RestApi } from "@aws-cdk/aws-apigateway"
+import { PolicyStatement } from "@aws-cdk/aws-iam"
+import { Function, Runtime, AssetCode, Code } from "@aws-cdk/aws-lambda"
+import { Construct, Duration, Stack, StackProps } from "@aws-cdk/core"
+import s3 = require("@aws-cdk/aws-s3")
+
+interface LambdaApiStackProps extends StackProps {
+    functionName: string
+}
+
+export class CDKExampleLambdaApiStack extends Stack {
+    private restApi: RestApi
+    private lambdaFunction: Function
+    private bucket: s3.Bucket
+
+    constructor(scope: Construct, id: string, props: LambdaApiStackProps) {
+        super(scope, id, props)
+
+        this.bucket = new s3.Bucket(this, "WidgetStore")
+
+        this.restApi = new RestApi(this, this.stackName + "RestApi", {
+            deployOptions: {
+                stageName: "beta",
+                metricsEnabled: true,
+                loggingLevel: MethodLoggingLevel.INFO,
+                dataTraceEnabled: true,
+            },
+        })
+
+        const lambdaPolicy = new PolicyStatement()
+        lambdaPolicy.addActions("s3:ListBucket")
+        lambdaPolicy.addResources(this.bucket.bucketArn)
+
+        this.lambdaFunction = new Function(this, props.functionName, {
+            functionName: props.functionName,
+            handler: "handler.handler",
+            runtime: Runtime.NODEJS_10_X,
+            code: new AssetCode(`./src`),
+            memorySize: 512,
+            timeout: Duration.seconds(10),
+            environment: {
+                BUCKET: this.bucket.bucketName,
+            },
+            initialPolicy: [lambdaPolicy],
+        })
+
+        this.restApi.root.addMethod("GET", new LambdaIntegration(this.lambdaFunction, {}))
+    }
+}

typescript/lambda-api-ci/package.json

@@ -0,0 +1,46 @@
+{
+    "name": "lambda-api-ci",
+    "version": "0.1.0",
+    "bin": {
+        "lambda-api-ci": "bin/lambda-api-ci.js"
+    },
+    "scripts": {
+        "build": "npm run prettier && tsc && npm run build-lambda",
+        "build-lambda": "cd src && npm run build",
+        "watch": "tsc -w",
+        "test": "jest",
+        "cdk": "cdk",
+        "prettier": "prettier --write '**/{bin,lib,src,tst}/*.ts'"
+    },
+    "devDependencies": {
+        "aws-cdk": "*",
+        "@aws-cdk/core": "*",
+        "@aws-cdk/assert": "*",
+        "@aws-cdk/aws-apigateway": "*",
+        "@aws-cdk/aws-codebuild": "*",
+        "@aws-cdk/aws-codecommit": "*",
+        "@aws-cdk/aws-codepipeline": "*",
+        "@aws-cdk/aws-codepipeline-actions": "*",
+        "@aws-cdk/aws-cloudformation": "*",
+        "@types/jest": "^24.0.18",
+        "@types/node": "^13.7.0",
+        "jest": "^24.9.0",
+        "ts-jest": "^24.0.2",
+        "ts-node": "^8.1.0",
+        "typescript": "^3.8.3",
+        "prettier": "^2.0.4"
+    },
+    "dependencies": {
+        "aws-sdk": "^2.617.0",
+        "source-map-support": "^0.5.9"
+    },
+    "description": "* `npm run build`   compile typescript to js  * `npm run watch`   watch for changes and compile  * `npm run test`    perform the jest unit tests  * `cdk deploy`      deploy this stack to your default AWS account/region  * `cdk diff`        compare deployed stack with current state  * `cdk synth`       emits the synthesized CloudFormation template",
+    "main": "jest.config.js",
+    "directories": {
+        "lib": "lib",
+        "test": "test"
+    },
+    "keywords": [],
+    "author": "",
+    "license": "ISC"
+}

typescript/lambda-api-ci/src/handler.ts

@@ -0,0 +1,44 @@
+import { S3 } from "aws-sdk"
+
+const bucketName = process.env.BUCKET!
+
+// From https://docs.aws.amazon.com/cdk/latest/guide/serverless_example.html
+const handler = async function (event: any, context: any) {
+    const S3Client = new S3()
+
+    try {
+        var method = event.httpMethod
+
+        if (method === "GET") {
+            if (event.path === "/") {
+                const data = await S3Client.listObjectsV2({ Bucket: bucketName }).promise()
+                var body = {
+                    widgets: data.Contents!.map(function (e) {
+                        return e.Key
+                    }),
+                }
+                return {
+                    statusCode: 200,
+                    headers: {},
+                    body: JSON.stringify(body),
+                }
+            }
+        }
+
+        // We only accept GET for now
+        return {
+            statusCode: 400,
+            headers: {},
+            body: "We only accept GET /",
+        }
+    } catch (error) {
+        const body = error.stack || JSON.stringify(error, null, 2)
+        return {
+            statusCode: 400,
+            headers: {},
+            body: JSON.stringify(body),
+        }
+    }
+}
+
+export { handler }

typescript/lambda-api-ci/src/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "widgets-lambda",
+  "version": "1.0.0",
+  "description": "A simple Lambda function to fetch widgets. See https://docs.aws.amazon.com/cdk/latest/guide/serverless_example.html",
+  "main": "handler.js",
+  "scripts": {
+    "build": "tsc",
+    "watch": "tsc -w",
+    "test": "jest"
+  },
+  "devDependencies": {
+    "@types/node": "^13.7.0",
+    "jest": "^24.9.0",
+    "ts-jest": "^24.0.2",
+    "ts-node": "^8.1.0",
+    "typescript": "~3.8.3"
+  },
+  "dependencies": {
+    "aws-sdk": "^2.617.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/awsdocs/aws-cdk-guide/blob/master/doc_source/serverless_example.md"
+  },
+  "author": "",
+  "license": "ISC"
+}