Add updated custom CloudWatch logs integration guide

I followed the Elastic Beanstalk custom CloudWatch logs documentation, but stumbled into permissions errors. I've laid the issues out in great detail in my Stack Overflow question.

The problem is that the Elastic Beanstalk docs encourage the usage of the CloudWatch Logs agent, but it states the following:

This reference is for the older deprecated CloudWatch Logs agent. If you use Instance Metadata Service Version 2 (IMDSv2), you must use the new unified CloudWatch agent. Even if you are not using IMDSv2, we strongly recommend that you use the newer unified CloudWatch agent instead of the older logs agent.

I was able to create a new configuration file that sets up Elastic Beanstalk to use the new CloudWatch agent. You can check my Stack Overflow answer, but here's the gist of it:

.ebextensions/custom-cloudwatch-logs.config

container_commands:
  01_append_logs_config:
    command: |
      amazon-cloudwatch-agent-ctl -a append-config -m ec2 -c file:/tmp/custom-cloudwatch-config.json -s

files:
  "/tmp/custom-cloudwatch-config.json":
    mode: "000600"
    owner: root
    group: root
    content: |
      {
        "logs": {
          "logs_collected": {
            "files": {
              "collect_list": [
                {
                  "file_path": "/var/log/php-fpm/www-error.log",
                  "log_group_name": "/aws/elasticbeanstalk/Project-env/var/log/php-fpm/www-error.log",
                  "log_stream_name": "{instance_id}"
                }
              ]
            }
          }
        }
      }

The official Elastic Beanstalk docs should provide a solution that revolves around this new approach, rather than the outdated CloudWatch Logs agent.

awsdocs / aws-elastic-beanstalk-developer-guide

Add updated custom CloudWatch logs integration guide #150