API Proxy for SQS

Integrating API Gateway with SQS (Simple Queue Service)

If you want to process API Request asynchronously or add a queue in your application architecture, you landed to the right place.

This article shows how to Integrate Amazon API Gateway as a proxy for SQS (Simple Queue Service).

1. Create SQS queue

• Open AWS console in services, navigate to Simple Queue Service.
• Click on “Create New Queue”
• Give queue a name, in our case it is “sqs-lambda-demo” and hit “Create Queue”
• Remember Queue URL (AWS-ACCT-ID/queue-name) and Queue ARN (AWS-ACCT-ID:queue-name)

Step 1. Create SQS queue

2. Create IAM Policy

We will create IAM Policy and Role for AWS API Gateway to push Request Message to Queue.

• Select IAM, Navigate to “policies” and click on “Create Policy”.
• Open JSON editor and add the following policy, click on “Review Policy”, name policy as apig-sqs-send-msg-policy and hit “Create Policy”.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": "sqs:SendMessage",
            "Resource": "arn:aws:sqs:ap-southeast-1:123456789:sqs-lambda-demo"
        }
    ]
}

3. Create IAM Role

• Select IAM, Navigate to “Roles” and click on “Create Role”. Now, select “API Gateway” and click “Next:Permissions”.

Step 3.1 : Create IAM Role

• Give a name to the role you created. In my case, it’s apig-sqs-send-msg-role , notice that only attached policy is “AmazonAPIGatewayPushToCloudWatchLogs”.

Step 3.2 : Save IAM role

• Once role is created, edit the role and attach apig-sqs-send-msg-policy .

4. Create an API Structure

• Select API Gateway, click on “Create API”, name api as SQSProxy and hit “Create”.

Create API in AWS API Gateway

• Click on “Action” and “create resource” and resource as v1.
• Click on “v1”, and hit “action > create resource” to create enquque.
• Click on “enqueue” and hit “action > create method” and from dropdown select “POST”.

API Resource Structure

5. Integrate the API with SQS

• Click on the “POST” method, in “integration type” click on “AWS service”, provide region and AWS service as “SQS”.
• Set Path override to Queue Path created in step 1.
• Set execution role to the role created in step 3. and hit “save”.

POST method for enqueue resource

6. Modify API Request

• Click on “Integrate Request”

• Set HTTP header with Name as Content-Type and Mapped from as 'application/x-www-form-urlencoded .
• In “Request body passthrough” select never and click on “add mapping template”, name it as application/json and add the following snippet Action=SendMessage&MessageBody=$input.body. This step will transform your request body to the one accepted by SQS.

7. Test And Deploy

• AWS api gateway provides functionality to test the API.
• In the request body, add the test data.

{
    "data" : "test"
}

• If you followed all the steps correctly, you should get 200 status. yey!!!
• Click on the resource “enqueue” and from “actions” select “Deploy Api”.
• Select or create new stage and deploy the Api.

That’s it! Test your API and deploy in production.