[Enhancement]: Dockerfile with inline scripts

[Steven-Harris]

Testcontainers version

3.9.0

Using the latest Testcontainers version?

Yes

Host OS

Windows 11

Host arch

x86

.NET version

8.0.108

Docker version

Client:
 Version:           27.2.0
 API version:       1.45 (downgraded from 1.47)
 Go version:        go1.21.13
 Git commit:        3ab4256
 Built:             Tue Aug 27 14:17:17 2024
 OS/Arch:           windows/amd64
 Context:           default

Server:
 Engine:
  Version:          26.1.3
  API version:      1.45 (minimum version 1.24)
  Go version:       go1.22.5
  Git commit:       8e96db1c328d0467b015768e42a62c0f834970bb
  Built:            Sun Jul  7 17:34:20 2024
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          v1.7.17
  GitCommit:        3a4de459a68952ffb703bbe7f2290861a75b6b67
 runc:
  Version:          1.1.12
  GitCommit:        51d5e94601ceffbbd85688df1c928ecccbfa4685
 docker-init:
  Version:          0.19.0
  GitCommit:

Docker info

Client:
 Version:    27.2.0
 Context:    default
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.10.4
    Path:     C:\Users\<redacted>\.docker\cli-plugins\docker-buildx.exe
  compose: Docker Compose (Docker Inc.)
    Version:  v2.29.2
    Path:     C:\Users\<redacted>\.docker\cli-plugins\docker-compose.exe

Server:
 Containers: 6
  Running: 1
  Paused: 0
  Stopped: 5
 Images: 52
 Server Version: 26.1.3
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Using metacopy: false
  Native Overlay Diff: true
  userxattr: false
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 1
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 3a4de459a68952ffb703bbe7f2290861a75b6b67
 runc version: 51d5e94601ceffbbd85688df1c928ecccbfa4685
 init version:
 Security Options:
  seccomp
   Profile: builtin
 Kernel Version: 5.10.102.1-microsoft-standard-WSL2
 Operating System: Rancher Desktop WSL Distribution
 OSType: linux
 Architecture: x86_64
 CPUs: 24
 Total Memory: 15.47GiB
 Name: G9WG5S3
 ID: aa23d5ea-e978-4661-a673-02dd7790e5e8
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false

What happened?

Dockerfiles with inline bash scripts don't build properly. I'll be changing line 7 of the Dockerfile for these examples in the repo listed below. For all these instances, I verified that docker-compose could spin up the Dockerfile before trying it with TestContainers.

If the docker file contains COPY <<-"EOF" start.sh, testcontainers is throwing COPY failed: no source files were specified.

I've tried converting the COPY command into a run command, which gets me a bit further. The image builds, but it never starts. Using RUN cat <<"EOF" > start.sh yields, System.TimeoutException: The operation has timed out.

I can work around the issue by moving the inline script into its own bash file and pulling it into the Dockerfile instead.

Relevant log output

COPY failed: no source files were specified

OR 

System.TimeoutException: The operation has timed out

Additional information

https://github.com/Steven-Harris/testcontainers-inline-script-issue

[HofmeisterAn]

I don't think we can support this. AFAIK Heredoc is a BuildKit feature that is not available (or only partially available) via the Docker Engine API - sorry. Instead, you can use Testcontainer's WithResourceMapping or WithStartupCallback feature (or build it with the CLI and pass the image name to your test). Does this issue belong to: #1244 too?

[Steven-Harris]

Ok, thanks @HofmeisterAn. Although, shouldn't it be working when using a simple cat command? e.g. RUN cat <<"EOF" > start.sh?

I've been monitoring #1244 and looked in the Wiremock.net repo. Their dockerfile doesn't look anything like mine. Although maybe there is a modification being made that I can't see. It's hard to tell, since they didn't provide the Dockerfile in the issue.

[HofmeisterAn]

I am not sure, but I do not think it will work. If you disable BuildKit using $env:DOCKER_BUILDKIT=0, it will not work with the CLI either. You can find more information about the Heredoc syntax and its support here. If you would like to use Testcontainers' build capabilities, I believe the only options available are the two approaches mentioned above.