AppConfig local development improvement

When running the AWS AppConfig Agent, you need to specify the AWS Region where your AppConfig resources are located. The error you encountered is likely due to the missing SERVICE_REGION environment variable, which is required for the agent to know which AWS Region to connect to.

To resolve this issue, you should set the SERVICE_REGION environment variable to the appropriate AWS Region code (e.g., us-east-1, us-west-2) where your AppConfig resources are deployed. This can be done in different ways depending on your deployment method:

1. For the AWS AppConfig Agent running as a system service (as in your case), you can modify the service configuration to include the environment variable. You might need to edit the service file at /etc/systemd/system/aws-appconfig-agent.service to add:

Environment="SERVICE_REGION=us-west-2"

(Replace us-west-2 with your actual AWS Region)

2. For Lambda functions using the AWS AppConfig Agent extension, you would set the AWS_APPCONFIG_EXTENSION_SERVICE_REGION environment variable.

3. For container deployments like Amazon EKS DaemonSets, you would include the SERVICE_REGION in your manifest file.

After setting the environment variable, restart the service with:

sudo systemctl daemon-reload
sudo systemctl restart aws-appconfig-agent

Explicitly setting the AWS Region is a best practice when working with AWS services as it improves performance by avoiding the need for the SDK to consult the default Region provider chain, which can cause delays.
Sources
Configuring the AWS AppConfig Agent Lambda extension - AWS AppConfig
(Optional) Running AWS AppConfig as a DaemonSet in Amazon EKS - AWS AppConfig
Region specification missing from AWS client initialization | Amazon Q, Detector Library
Region specification missing from AWS client initialization | Amazon Q, Detector Library