AWS Lambda (sdk) InvalidAliasNameException encountered when attempting to create or update an alias in AWS Lambda.

Understanding AWS Lambda

AWS Lambda is a serverless compute service that allows you to run code without provisioning or managing servers. It automatically scales your application by running code in response to each trigger. Lambda functions can be triggered by various AWS services, making it a versatile tool for developers looking to build scalable applications.

Recognizing the Symptom

When working with AWS Lambda, you might encounter the InvalidAliasNameException. This error typically arises when you attempt to create or update an alias for a Lambda function, and the alias name does not conform to the required naming conventions.

What You See

The error message will explicitly state that the alias name is invalid, which can halt your deployment or update process.

Exploring the Issue

The InvalidAliasNameException is thrown when the alias name provided does not meet AWS Lambda's naming requirements. An alias in AWS Lambda is a pointer to a specific version of a Lambda function, and it allows you to manage different environments (like development, testing, and production) more effectively.

Alias Naming Requirements

According to AWS Lambda's documentation, alias names must:

• Be between 1 and 128 characters in length.
• Contain only alphanumeric characters, hyphens (-), and underscores (_).
• Not begin with the reserved prefix aws.

For more details, refer to the AWS Lambda Alias Configuration documentation.

Steps to Fix the Issue

To resolve the InvalidAliasNameException, follow these steps:

Step 1: Verify Alias Name

Ensure that the alias name you are using meets the naming requirements. Double-check for any illegal characters or reserved prefixes.

Step 2: Update Alias Name

If the alias name is incorrect, update it to comply with the requirements. For example, if your alias name is aws_dev, change it to dev or development.

Step 3: Use AWS CLI or SDK

Use the AWS CLI or SDK to update or create the alias with the correct name. Here is an example command using AWS CLI:

aws lambda create-alias --function-name my-function --name myAlias --function-version 1

Ensure that myAlias is a valid alias name.

Conclusion

By ensuring that your alias names meet AWS Lambda's naming conventions, you can avoid the InvalidAliasNameException and streamline your function management process. For further reading, check out the AWS Lambda Documentation.