How bootstrap-container's user-data works?

[yaroslav-nakonechnikov]

Hello,

I'm trying to use aws-cli image. As input it waits some command for it.

and i tried to put encoded help (aGVscAo=), and expected to see message, which i can get locally by:

docker run amazon/aws-cli:latest help

config:

[settings.bootstrap-containers.aws]
              source = "amazon/aws-cli:latest"
              mode = "once"
              essential = false
              user-data = "aGVscAo="

but all i get - is the error:

Jan 24 12:47:42 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: time="2024-01-24T12:47:42Z" level=info msg="unpacking image..." img="amazon/aws-cli:latest"
Jan 24 12:47:49 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: time="2024-01-24T12:47:49Z" level=info msg="Container does not exist, proceeding to create it" ctr-id=boot.ssm
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: time="2024-01-24T12:47:50Z" level=info msg="container task does not exist, proceeding to create it" container-id=boot.ssm
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: time="2024-01-24T12:47:50Z" level=info msg="successfully started container task"
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: usage: aws [options] <command> <subcommand> [<subcommand> ...] [parameters]
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: To see help text, you can run:
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]:   aws help
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]:   aws <command> help
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]:   aws <command> <subcommand> help
Jan 24 12:47:50 ip-10-216-35-53.eu-central-1.compute.internal host-ctr[1624]: aws: error: the following arguments are required: command

so, how user-data is being passed?

[gthao313]

@yaroslav-nakonechnikov Thanks for starting this conversation.

After digging into the aws-cli image, I don't think aws-cli container has the mechanism to support you to input user-data there. More useful info here, Which means you are unable to config the user-data on aws-cli container.

If you need to use a container that knows how to read user-data, I would suggest your to use the container like AmazonLinux container : ).

Please let me know if you have more questions. thanks!

[yaroslav-nakonechnikov]

yes, i saw docker file. But it doesn't give me details.

i want to know how that user-data is being passed to container. If it should be just string as it is written, so just help should provide correct output in the logs and exit code is 0.
But it is not like that.

[yaroslav-nakonechnikov]

i found one example: https://github.com/stefansundin/bottlerocket-bootstrap-associate-eip
but it also looks like passing string. and it also have entrypoint and nothing which is called user-data

[gthao313]

I think you could do the above way. The example you linked has a rust tool reading the user-data -> https://github.com/stefansundin/bottlerocket-bootstrap-associate-eip/blob/main/src/main.rs.

FYI, we have new guides here. https://bottlerocket.dev/en/os/1.18.x/concepts/bootstrap-containers/ and https://bottlerocket.dev/en/os/1.18.x/api/settings/bootstrap-containers/.

[yaroslav-nakonechnikov]

so, that user-data is a file, which should be read additionally?
and entrypoint should look like: bash /.bottlerocket/bootstrap-containers/current/user-data (in case user data is bash script)?

[gthao313]

I think you are correct. I just tried on my end and the bash ./user-data did the right thing without setting the exec flag in the user data file.

Meanwhile, we have an opening issue that takes the user data and execute it as a shell script. Feel free to left comments there!
#2010