Added Auth Lambda

bin/chat_api_app_sync.ts

@@ -1,21 +1,19 @@
 #!/usr/bin/env node
-import 'source-map-support/register';
-import * as cdk from '@aws-cdk/core';
-import { ChatApiAppSyncStack } from '../lib/chat_api_app_sync-stack';
+import "source-map-support/register";
+import * as cdk from "@aws-cdk/core";
+import { ChatApiAppSyncStack } from "../lib/chat_api_app_sync-stack";
 
 const app = new cdk.App();
-new ChatApiAppSyncStack(app, 'ChatApiAppSyncStack', {
+new ChatApiAppSyncStack(app, "ChatApiAppSyncStack", {
   /* If you don't specify 'env', this stack will be environment-agnostic.
    * Account/Region-dependent features and context lookups will not work,
    * but a single synthesized template can be deployed anywhere. */
-
   /* Uncomment the next line to specialize this stack for the AWS Account
    * and Region that are implied by the current CLI configuration. */
   // env: { account: process.env.CDK_DEFAULT_ACCOUNT, region: process.env.CDK_DEFAULT_REGION },
-
   /* Uncomment the next line if you know exactly what Account and Region you
    * want to deploy the stack to. */
   // env: { account: '123456789012', region: 'us-east-1' },
-
   /* For more information, see https://docs.aws.amazon.com/cdk/latest/guide/environments.html */
+  env: { region: "ap-south-1" },
 });

lib/auth-lambda.construct.ts

@@ -0,0 +1,20 @@
+import * as cdk from "@aws-cdk/core";
+import * as iam from "@aws-cdk/aws-iam";
+import * as nodeLambda from "@aws-cdk/aws-lambda-nodejs";
+
+export class AuthLambdaConstruct extends cdk.Stack {
+  readonly lambda: nodeLambda.NodejsFunction;
+  constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    this.lambda = new nodeLambda.NodejsFunction(this, "AppSyncAuthHandler", {
+      functionName: `custom-authoriser`,
+      description: `This Lambda is excuted fauthenticate the user.`,
+      retryAttempts: 0,
+      entry: "src/lambdas/auth.ts",
+      handler: "handler",
+    });
+
+    this.lambda.grantInvoke(new iam.ServicePrincipal("appsync.amazonaws.com"));
+  }
+}

lib/chat_api_app_sync-stack.ts

@@ -1,115 +1,65 @@
 import * as cdk from "@aws-cdk/core";
-import * as cdkCore from "@aws-cdk/core";
-import * as appsync from "@aws-cdk/aws-appsync";
-import * as dynamoDb from "@aws-cdk/aws-dynamoDb";
-import * as lambda from "@aws-cdk/aws-lambda";
-// import { Code, Function, Runtime } from '@aws-cdk/aws-lambda';
-// import * as sqs from '@aws-cdk/aws-sqs';
+import { GraphQlAPIConstruct } from "./graph-api.construct";
+import { LambdaConstruct } from "./lambda.contruct";
+import { DynamoDBConstruct } from "./dynamo-db.construct";
 
 export class ChatApiAppSyncStack extends cdk.Stack {
   constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
     super(scope, id, props);
 
-    const MessagesTable = new dynamoDb.Table(this, "MessagesTable", {
-      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
-      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
-      sortKey: { name: "conversationId", type: dynamoDb.AttributeType.STRING },
-      removalPolicy: cdkCore.RemovalPolicy.DESTROY,
-      tableName: "messages-table",
-    });
+    const dynamoDBConstruct = new DynamoDBConstruct(
+      this,
+      `${id}-dynamo-db`,
+      props
+    );
 
-    const ConversationsTable = new dynamoDb.Table(this, "ConversationsTable", {
-      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
-      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
-      removalPolicy: cdkCore.RemovalPolicy.DESTROY,
-      tableName: "conversations-table",
-    });
+    const lambdaConstruct = new LambdaConstruct(this, `${id}-lambda`, props);
 
-    const UsersTable = new dynamoDb.Table(this, "UsersTable", {
-      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
-      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
-      removalPolicy: cdkCore.RemovalPolicy.DESTROY,
-      tableName: "users-table",
-    });
+    const graphAPIContruct = new GraphQlAPIConstruct(
+      this,
+      `${id}-graph-api`,
+      props
+    );
 
-    const api = new appsync.GraphqlApi(this, "ChatsApi", {
-      name: "chat-api",
-      logConfig: {
-        fieldLogLevel: appsync.FieldLogLevel.ERROR,
-      },
-      schema: appsync.Schema.fromAsset("src/graphql/schema.graphql"),
-      authorizationConfig: {
-        defaultAuthorization: {
-          authorizationType: appsync.AuthorizationType.API_KEY,
-          apiKeyConfig: {
-            expires: cdk.Expiration.after(cdk.Duration.days(365)),
-          },
-        },
-      },
-      // xrayEnabled: true,
-    });
+    // enable the Lambda function to access the DynamoDB table (using IAM)
+    dynamoDBConstruct.messagesTable.grantFullAccess(lambdaConstruct.lambda);
+    dynamoDBConstruct.notificationTable.grantFullAccess(lambdaConstruct.lambda);
+    dynamoDBConstruct.conversationsTable.grantFullAccess(
+      lambdaConstruct.lambda
+    );
+    dynamoDBConstruct.usersTable.grantFullAccess(lambdaConstruct.lambda);
+
+    // Create an environment variable that we will use in the function code
+    lambdaConstruct.lambda.addEnvironment(
+      "MESSAGES_TABLE",
+      dynamoDBConstruct.messagesTable.tableName
+    );
+    lambdaConstruct.lambda.addEnvironment(
+      "CONVERSATIONS_TABLE",
+      dynamoDBConstruct.conversationsTable.tableName
+    );
+    lambdaConstruct.lambda.addEnvironment(
+      "USERS_TABLE",
+      dynamoDBConstruct.usersTable.tableName
+    );
+    lambdaConstruct.lambda.addEnvironment(
+      "NOTIFICATIONS_TABLE",
+      dynamoDBConstruct.notificationTable.tableName
+    );
 
     // Prints out the AppSync GraphQL endpoint to the terminal
     new cdk.CfnOutput(this, "GraphQLAPIURL", {
-      value: api.graphqlUrl,
+      value: graphAPIContruct.api.graphqlUrl,
     });
 
     // Prints out the AppSync GraphQL API key to the terminal
     new cdk.CfnOutput(this, "GraphQLAPIKey", {
-      value: api.apiKey || "",
+      value: graphAPIContruct.api.apiKey || "",
     });
 
     // Prints out the stack region to the terminal
     new cdk.CfnOutput(this, "Stack Region", {
       value: this.region,
     });
-
-    // const chatsLambda = new lambda.Function(this, "AppSyncChatRouteHandler", {
-    //   runtime: lambda.Runtime.NODEJS_12_X,
-    //   handler: "routes.handler",
-    //   code: lambda.Code.fromAsset("src"),
-    //   memorySize: 1024,
-    // });
-
-    // // Set the new Lambda function as a data source for the AppSync API
-    // const lambdaDs = api.addLambdaDataSource("lambdaDatasource", chatsLambda);
-
-    // lambdaDs.createResolver({
-    //   typeName: "Query",
-    //   fieldName: "getConversations",
-    // });
-
-    // lambdaDs.createResolver({
-    //   typeName: "Query",
-    //   fieldName: "getConversation",
-    // });
-
-    // lambdaDs.createResolver({
-    //   typeName: "Mutation",
-    //   fieldName: "addConversation",
-    // });
-
-    // lambdaDs.createResolver({
-    //   typeName: "Mutation",
-    //   fieldName: "addMessage",
-    // });
-
-    // lambdaDs.createResolver({
-    //   typeName: "Mutation",
-    //   fieldName: "addUser",
-    // });
-
-    // enable the Lambda function to access the DynamoDB table (using IAM)
-    // MessagesTable.grantFullAccess(chatsLambda);
-    // ConversationsTable.grantFullAccess(chatsLambda);
-    // UsersTable.grantFullAccess(chatsLambda);
-
-    // // Create an environment variable that we will use in the function code
-    // chatsLambda.addEnvironment("MESSAGES_TABLE", MessagesTable.tableName);
-    // chatsLambda.addEnvironment(
-    //   "CONVERSATIONS_TABLE",
-    //   ConversationsTable.tableName
-    // );
-    // chatsLambda.addEnvironment("USERS_TABLE", UsersTable.tableName);
   }
 }

lib/dynamo-db.construct.ts

@@ -0,0 +1,43 @@
+import * as cdk from "@aws-cdk/core";
+import * as dynamoDb from "@aws-cdk/aws-dynamoDb";
+
+export class DynamoDBConstruct extends cdk.Stack {
+  readonly messagesTable: dynamoDb.Table;
+  readonly conversationsTable: dynamoDb.Table;
+  readonly usersTable: dynamoDb.Table;
+  readonly notificationTable: dynamoDb.Table;
+
+  constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    this.messagesTable = new dynamoDb.Table(this, "MessagesTable", {
+      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
+      partitionKey: { name: "conversationId", type: dynamoDb.AttributeType.STRING },
+      sortKey: { name: "createdAt", type: dynamoDb.AttributeType.STRING },
+      removalPolicy: cdk.RemovalPolicy.DESTROY,
+      tableName: "messages-table",
+    });
+
+    this.conversationsTable = new dynamoDb.Table(this, "ConversationsTable", {
+      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
+      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
+      removalPolicy: cdk.RemovalPolicy.DESTROY,
+      tableName: "conversations-table",
+    });
+
+    this.usersTable = new dynamoDb.Table(this, "UsersTable", {
+      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
+      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
+      removalPolicy: cdk.RemovalPolicy.DESTROY,
+      tableName: "users-table",
+    });
+
+    this.notificationTable = new dynamoDb.Table(this, "NotificationsTable", {
+      billingMode: dynamoDb.BillingMode.PAY_PER_REQUEST,
+      partitionKey: { name: "id", type: dynamoDb.AttributeType.STRING },
+      sortKey: { name: "createdAt", type: dynamoDb.AttributeType.STRING },
+      removalPolicy: cdk.RemovalPolicy.DESTROY,
+      tableName: "notifications-table",
+    });
+  }
+}

lib/graph-api.construct.ts

@@ -0,0 +1,36 @@
+import * as cdk from "@aws-cdk/core";
+import * as appsync from "@aws-cdk/aws-appsync";
+import * as nodeLambda from "@aws-cdk/aws-lambda-nodejs";
+import * as iam from "@aws-cdk/aws-iam";
+import { AuthLambdaConstruct } from "./auth-lambda.construct";
+
+export class GraphQlAPIConstruct extends cdk.Stack {
+  readonly api: appsync.GraphqlApi;
+  constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    const athLambdaConstruct = new AuthLambdaConstruct(
+      this,
+      `${id}-auth-lambda`,
+      props
+    );
+
+    this.api = new appsync.GraphqlApi(this, "ChatsApi", {
+      name: "chat-api",
+      schema: appsync.Schema.fromAsset("src/graphql/schema.graphql"),
+      authorizationConfig: {
+        defaultAuthorization: {
+          authorizationType: appsync.AuthorizationType.LAMBDA,
+          lambdaAuthorizerConfig: {
+            handler: athLambdaConstruct.lambda,
+          },
+          // // API Key Authentication
+          // authorizationType: appsync.AuthorizationType.API_KEY,
+          // apiKeyConfig: {
+          //   expires: cdk.Expiration.after(cdk.Duration.days(365)),
+          // },
+        },
+      },
+    });
+  }
+}

lib/graphql/graphql-resolvers.ts

@@ -0,0 +1,60 @@
+import * as appsync from "@aws-cdk/aws-appsync";
+import * as nodeLambda from "@aws-cdk/aws-lambda-nodejs";
+
+export const bindResolvers = (
+  api: appsync.GraphqlApi,
+  lambda: nodeLambda.NodejsFunction
+) => {
+  // Set the new Lambda function as a data source for the AppSync API
+  const lambdaDs = api.addLambdaDataSource("lambdaDatasource", lambda);
+
+  lambdaDs.createResolver({
+    typeName: "Query",
+    fieldName: "conversations",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Query",
+    fieldName: "users",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Query",
+    fieldName: "conversation",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Query",
+    fieldName: "notifications",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Mutation",
+    fieldName: "createConversation",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Mutation",
+    fieldName: "addMessage",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Mutation",
+    fieldName: "createUser",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Mutation",
+    fieldName: "addNotification",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Subscription",
+    fieldName: "onCreateUser",
+  });
+
+  lambdaDs.createResolver({
+    typeName: "Subscription",
+    fieldName: "onCreateNotification",
+  });
+};

lib/lambda.contruct.ts

@@ -0,0 +1,21 @@
+import * as cdk from "@aws-cdk/core";
+import * as nodeLambda from "@aws-cdk/aws-lambda-nodejs";
+
+export class LambdaConstruct extends cdk.Stack {
+  readonly lambda: nodeLambda.NodejsFunction;
+  constructor(scope: cdk.Construct, id: string, props?: cdk.StackProps) {
+    super(scope, id, props);
+
+    this.lambda = new nodeLambda.NodejsFunction(
+      this,
+      "AppSyncChatRouteHandler",
+      {
+        functionName: `chat-routing`,
+        description: `This Lambda is excuted from graphql to trigger lambda.`,
+        retryAttempts: 0,
+        entry: "src/routes.ts",
+        handler: "handler",
+      }
+    );
+  }
+}