Create a docker compose file for demo setup

[MadsNielsen]

Should use a specific version of jenkins4casc and docker version 3.3 so we can use docker secrets.

It should reference docker secrets we create manually on the EC2 instance docker host.

It should reference a jenkins.yml in this repository, using an environment variable and point to the raw content of the jenkins.yml

[buep]

Related to https://github.com/Praqma/praqma-jenkins-casc/issues/8

[buep]

We won't need history, nor backup, as it is only a demo instance and new builds will come again when there is activity in projects. Else we simple run some.

[MadsNielsen]

Basic setup working in docker compose with secrets and master.

[buep]

You mentioned a bug in docker compose, leading to this change in CasC https://github.com/jenkinsci/configuration-as-code-plugin/commit/c83470c3b842358bbbbbb3f6af996dfa278953af

Can you please check the file outside and inside the container using cat -A https://linuxaria.com/pills/linux-terminal-seeing-the-unseen-characters-with-cat to verify it is a bug in docker-compose?

No matter what we can not commit to CASC project without an issue or PR... so please revert that commit and create a proper issues describing the problem there - if the problem really is with CasC and not docker compose.

FYI @ewelinawilkosz

[buep]

md5sum could also be used to verify the files are identical ?

[MadsNielsen]

cat with the -A switch inside container:

jenkins@5e53860188b8:/$ cat -A /run/secrets/adminpw
secr3t$

cat with the -A switch from the host system:

mads@mads-UX302LG:/var/deploy/secrets$ cat -A /var/deploy/secrets/adminpw
secr3t$

[buep]

CAT(1)                                                                                          User Commands                                                                                          CAT(1)

NAME
       cat - concatenate files and print on the standard output

SYNOPSIS
       cat [OPTION]... [FILE]...

DESCRIPTION
       Concatenate FILE(s) to standard output.

       With no FILE, or when FILE is -, read standard input.

       -A, --show-all
              equivalent to -vET

       -b, --number-nonblank
              number nonempty output lines, overrides -n

       -e     equivalent to -vE

       -E, --show-ends
              display $ at end of each line

       -n, --number
              number all output lines

       -s, --squeeze-blank
              suppress repeated empty output lines

       -t     equivalent to -vT

       -T, --show-tabs
              display TAB characters as ^I

       -u     (ignored)

       -v, --show-nonprinting
              use ^ and M- notation, except for LFD and TAB

       --help display this help and exit

       --version
              output version information and exit

[MadsNielsen]

mads@mads-UX302LG:/var/deploy/secrets$ cat /var/deploy/secrets/adminpw
secr3t
mads@mads-UX302LG:/var/deploy/secrets$

jenkins@5e53860188b8:/$ cat /run/secrets/adminpw
secr3t
jenkins@5e53860188b8:/$ 

[buep]

So with the above I would conclude docker compose work correctly and as expected - it do not change the file passed in through secrets.

The problem must be they way we read it in CasC https://github.com/jenkinsci/configuration-as-code-plugin/blob/master/src/main/java/org/jenkinsci/plugins/casc/DockerSecretSource.java#L21