Cognito on REST APIs

What is AWS Cognito?

AWS Cognito is a user authentication and management service that helps developers to add user sign-up, sign-in, and access control to their applications. It provides a secure user directory that can be used to manage users and their access to AWS resources and applications. It also supports social identity providers such as Facebook, Google, and Amazon.

Steps to Configure and Use AWS Cognito on REST APIs

In this section, we will go through the steps required to configure and use AWS Cognito on REST APIs.

Step 1: Create a User Pool

The first step is to create a user pool in AWS Cognito. A user pool is a user directory that can be used to manage users and their access to AWS resources and applications.

1. Go to the AWS Management Console and navigate to the Cognito service.
2. Click on “Manage User Pools” and then click on “Create a user pool”.
3. Enter a name for the user pool and click on “Review defaults”.
4. Review the default settings and click on “Create pool” to create the user pool.

Step 2: Configure App Clients

The next step is to configure app clients in the user pool. App clients are the applications that will be using the user pool for user authentication and management.

1. Go to the user pool that you created in step 1.
2. Click on “App clients” and then click on “Add an app client”.
3. Enter a name for the app client and select the appropriate settings.
4. Click on “Create app client” to create the app client.

Step 3: Create API Gateway

The next step is to create an API Gateway. API Gateway is a fully managed service that makes it easy for developers to create, publish, maintain, monitor, and secure APIs.

1. Go to the AWS Management Console and navigate to the API Gateway service.
2. Click on “Create API” and then select “REST API”.
3. Select “New API” and enter a name for the API.
4. Click on “Create API” to create the API.

Step 4: Create Resources and Methods

The next step is to create resources and methods in the API Gateway. Resources are the entities that represent the API endpoints, and methods are the actions that can be performed on those endpoints.

1. Click on “Create Resource” to create a new resource.
2. Enter a name for the resource and click on “Create Resource”.
3. Click on the resource that you just created and then click on “Create Method”.
4. Select the appropriate HTTP method (e.g., GET, POST, PUT, DELETE) and click on “Save”.

Step 5: Configure Authorization

The next step is to configure authorization in the API Gateway. Authorization is the process of granting access to specific users or groups to perform specific actions on the API.

1. Click on the method that you just created and then click on “Method Request”.
2. Click on the pencil icon next to “Authorization” and select “AWS_IAM”.
3. Click on “Save”.
4. Click on “Integration Request”.
5. Click on the pencil icon next to “Authorization” and select “AWS_IAM”.
6. Click on “Save”.

Step 6: Configure Cognito Authorizer

The next step is to configure the Cognito authorizer in the API Gateway. The Cognito authorizer will authenticate the user and authorize the user’s access to the API.

1. Click on the method that you just created and then click on “Integration Request”.
2. Scroll down to “Lambda Function” and click on the pencil icon.
3. Select “Use Lambda Proxy integration” and enter the name of your Lambda function.
4. Click on “Save”.
5. Click on “Method Execution” and then click on “Integration Response”.
6. Expand the “Lambda Proxy” section and click on the pencil icon next to “Authorization”.
7. Select “Cognito” and enter the details for your Cognito user pool and app client.
8. Click on “Save”.

Step 7: Test the API

The final step is to test the API to ensure that everything is working as expected.

1. Click on the method that you just created and then click on “Test”.
2. Enter the required parameters and click on “Test”.
3. Verify that the response is as expected.

Conclusion

In this blog post, we went through the steps required to configure and use AWS Cognito on REST APIs. By using AWS Cognito, developers can add user sign-up, sign-in, and access control to their applications quickly and easily. It provides a secure user directory that can be used to manage users and their access to AWS resources and applications. By following the steps outlined in this blog post, developers can easily set up AWS Cognito on REST APIs and secure their applications.