Introducing the new Amazon Q Developer experience in AWS Lambda

AWS Lambda recently announced a new code editor based on Code-OSS. Like the previous version, the new editor includes Amazon Q Developer. Amazon Q Developer is a generative AI-powered assistant for software development that can help you build and debug Lambda functions more quickly. In this post, I provide an overview of Amazon Q Developer’s integration into the new built-in code editor.

Introduction

AWS Lambda first supported Amazon Q Developer in 2022 (previously known as Amazon CodeWhisperer). While Q Developer has added many features since 2022, the experience in the Lambda editor has remained mostly unchanged until recently. For example, the quality and length of recommendations has increased significantly over the past two years. The original blog post announcing support for Q Developer in the Lambda editor (then called CodeWhisperer) used a series of prompts such as “upload a file to an S3 bucket” or “send a notification using SNS” to incrementally build a Lambda function. While that was impressive at the time, Q Developer can now accept much longer and more complex prompts. For example, I asked Q Developer to create an image moderation function with the following comment. This comment will result in about seventy lines of Python code, including whitespace.

This function moderates images uploaded to S3. It is invoked by an S3 event notification when a new image is uploaded. First, it calls Rekognition image moderation. It also uses Rekognition to extract text from the image, and uses Comprehend to check for toxic content. Finally, it sends a message to the SQS queue identified in the env var QUEUE_URL if the image was moderated or if it contained toxic content. The env var MIN_SCORE allows configuration of the confidence score used as the threshold for both moderation and toxicity.

While I can use this comment in both the old and new editor, the experience in the new editor has significantly improved. Note that in the following image of the old editor, I can only see the first eight lines of the suggestion in a popup. I have to scroll to review the remaining 62 lines of code. The old editor experience did not anticipate that Q Developer would someday return 70 lines, or more, in a single response.

The experience in the new editor is much improved as shown in the following image. I can preview the entire suggestion in-line with my code, up to the size of my screen. This makes it much easier to evaluate the suggestion before deciding to accept or decline it.

Now that you have seen the new editor in action, let’s discuss how to configure and use it.

Inline completions in Lambda

Q Developer can provide you with code recommendations in real time. As you write code, Q Developer automatically generates suggestions based on your existing code and comments. Before I can use Q Developer in the Lambda console, I must first configure it as described in Using Amazon Q Developer with AWS Lambda. With that done, I am ready to start with a simple example.

While I love Python, I often find myself working with a dictionary object without knowledge of its structure. As a result, I waste time reading the documentation searching for the names of various keys. In Lambda, the event object is passed as a dictionary. In addition, each event type has a different structure. Q Developer can save me countless hours of reading documentation to find the structure of each event.

As an example, imagine that I have created a function that can be triggered by Amazon API Gateway, Application Load Balancer, and AWS AppSync. I need to get the IP address of the client that invoked my function. While this is available in the X-Forwarded-For header, the location and format of the header in the dictionary is subtly different in each event type. Q Developer can save me a trip to the documentation.

In the example below, Q Developer is making the correct suggestion for API Gateway based on the contextual clues in my file. Specifically, the comments on lines one and three. When I hit enter at the end of line three, Q Developer uses the context to recommend the code on line four. Note that it correctly recommends X-Forwarded-For with capitals for an API Gateway event.

However, in the next example, the comment on line one now mentions an Application Load Balancer. Note that Q Developer correctly recommends x-forwarded-for in lower-case for an Application Load Balancer event.

That trivial example just saved me a trip to the documentation that would have taken three to five minutes. If I can do that a few times every hour, it has a huge impact on my productivity and focus due to less context switching.

While the in-line completion experience is greatly improved in the new editor, Q Developer supports other capabilities in the Lambda console that I do not want to overlook. Let’s take a moment to review chat and troubleshooting, which are unchanged with the release of the new editor.

Chat in the Lambda console

Q Developer supports chat in the Lambda console. I can use this to ask questions rather than reading through the documentation. Returning to my original example, the image moderation function, remember that my function expects two environment variables, QUEUE_URL andMIN_SCORE.Imagine that I do not know how to configure an environment variable in the Lambda console. In the following example, I chat with Q Developer to ask for help.

Note that the response is aware of my position in the console. Q Developer says “It looks like you’re already in the function design.” Q Developer not only saves me a trip to the documentation, but it tailors the suggestion to my current position so I do not have to read unnecessary instructions. I will follow Q Developer’s instructions to configure the two required environment variables as shown below.

You can see how chat is able to help keep me on task and in a state of flow. Next, I will show you how Q Developer can help you troubleshoot issues in the console.

Troubleshooting in the Lambda console

With the environment variables configured, I am ready to test my function. However, when I run a test, I get an error message as shown in the following image. Note the “Diagnose with Amazon Q” button. Q Developer noticed that I am having issues, and is offering to help.

If I select the “Diagnose with Amazon Q” button, Q Developer will analyze the error. In the example below, you can see that it has identified that “the Lambda function is unable to access an object in S3.” Of course! I never granted the Lambda function permission to access the Amazon Simple Storage Service (Amazon S3) bucket.

I could go back to the chat pane I used earlier and ask Q Developer how to add permissions. However, notice that it already provides set-by-step instructions to fix the issue. So, I don’t even need to use the chat. Once I fix the permissions, my function is working as expected. Q Developer has saved me time and made me much more productive.

Cleanup

If you have been following along and deployed a Lambda function, please remember to delete it.

Conclusion

The new AWS Lambda built-in editor experience greatly improves the Q Developer inline suggestion experience for Lamba. This new editor, combined with the existing chat and troubleshooting capabilities can significantly improve your productivity. To learn more read Getting started with Amazon Q Developer and Using Amazon Q Developer with AWS Lambda.