Json log format not working since v1.44.0 (ECS_LOG_OUTPUT_FORMAT)

[adebasi]

Summary

The output format json, configured via ECS_LOG_OUTPUT_FORMAT, doesn't have any effect from version 1.44.0 on.

Description

In version 1.36.0 the output format json was introduced. Users were able to set the format to json by setting the env var ECS_LOG_OUTPUT_FORMAT. From 1.44.0 this seems to be broken and I was not able to find something related to this in the changelog.

I verified this behaviour by running containers with different versions:

$ docker run -e ECS_LOG_OUTPUT_FORMAT=json amazon/amazon-ecs-agent:v1.43.0
{"level": "info", "time": "2020-08-27T07:33:10Z", "msg": "Loading configuration", "module": "agent.go"}

$ docker run -e ECS_LOG_OUTPUT_FORMAT=json amazon/amazon-ecs-agent:v1.44.0
1598513604929243900 [Error] node must have children
1598513604932176700 [Info] Loading configuration

I noticed this error because I updated our agents to version 1.44.1 and setting ECS_LOG_OUTPUT_FORMAT to json had no effect.

Expected Behavior

Set ECS_LOG_OUTPUT_FORMAT to json has the effect that the container logs are in json format.

Observed Behavior

see description

[ubhattacharjya]

Hi @adebasi ,

I am sorry to hear that you are facing this problem. I am investigating the issue from my end. I will update you with my findings.

Utsa

[ubhattacharjya]

Hi @adebasi ,

I could reproduce the error that you faced.

Kindly use the following workaround:

docker run -e ECS_LOG_OUTPUT_FORMAT=json -e ECS_LOGFILE=/log/ecs-agent.log amazon/amazon-ecs-agent:v1.44.0

Let me know if you are still facing the issue

Utsa

[ubhattacharjya]

The PR for fixing this issue : https://github.com/aws/amazon-ecs-agent/pull/2598/files

[adebasi]

Hi @ubhattacharjya,
Thank you for the quick response and fixing the bug.

[ellenthsu]

This fix has been released as part of ECS Agent 1.44.4: https://github.com/aws/amazon-ecs-agent/releases/tag/1.44.4

Please perform an update of the Agent: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-agent-update.html or you can find the latest ECS Optimized AMIs containing ECS Agent 1.44.4 here: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-optimized_AMI.html