How does one integrate DynamoDB Local into the development process when using aws-cdk? For example, the following app (using the "sample app" template) works, but how would one run sam local invoke <id of the backendHandler lambda>
and point to a DynamoDB Local instance running on your machine (instead of having to run cdk deploy
) to see in action?
// lib/minimal-app-stack.ts
import * as apiGateway from "@aws-cdk/aws-apigateway";
import * as cdk from "@aws-cdk/core";
import {MinimalBackend} from "./minimal-backend";
export class MinimalAppStack extends cdk.Stack {
constructor(scope: cdk.App, id: string, props?: cdk.StackProps) {
super(scope, id, props);
const minimalBackend = new MinimalBackend(this, "MinimalBackend");
new apiGateway.LambdaRestApi(this, "Endpoint", {
handler: minimalBackend.handler
});
}
}
// lib/minimal-backend.ts
import * as cdk from "@aws-cdk/core";
import * as dynamodb from "@aws-cdk/aws-dynamodb";
import * as lambda from "@aws-cdk/aws-lambda";
export class MinimalBackend extends cdk.Construct {
public readonly handler: lambda.Function;
constructor(scope: cdk.Construct, id: string) {
super(scope, id);
const minimalTable = new dynamodb.Table(this, "MinimalTable", {
partitionKey: {
name: "id",
type: dynamodb.AttributeType.STRING
}
});
this.handler = new lambda.Function(this, "BackendHandler", {
code: lambda.Code.fromAsset("lambda"),
handler: "backendHandler.handler",
runtime: lambda.Runtime.NODEJS_12_X,
environment: {
TABLE_NAME: minimalTable.tableName
}
});
minimalTable.grantReadWriteData(this.handler);
}
}
// lambda/backendHandler.ts
// @ts-ignore
/// <reference types="aws-sdk" />
import AWS = require("aws-sdk");
const tableName = process.env.TABLE_NAME || "";
const dynamo = new AWS.DynamoDB.DocumentClient();
async function getAllItems() {
const scanResult = await dynamo
.scan({
TableName: tableName
})
.promise();
return scanResult;
}
exports.handler = async function (event: AWSLambda.APIGatewayEvent) {
const response = await getAllItems();
const data = response.Items || [];
const stringifiedData = JSON.stringify(data, undefined, 2);
return {
statusCode: 200,
headers: {
"Access-Control-Allow-Origin": "*",
"Access-Control-Allow-Methods": "OPTIONS,GET,POST,DELETE"
},
body: stringifiedData
}
};
If I was inside a plain node app, I could access my DynamoDB Local instance with:
const docClient = new AWS.DynamoDB.DocumentClient( {
region: "us-west-2",
endpoint: "http://localhost:8000",
convertEmptyValues: true
});
Not sure how to integrate that into aws-cdk though. Any ideas?