Add development environment using dev container

[R-HNF]

Description

Changes

• Add Dockerfile.dev and devcontainer.json to use dev container on Visual Studio Code.
• Modified the Dockerfile to not be fixed to amd64.
  • I have verified the test in the arm environment using the development container on my M2 Mac and Intel Windows.
• There are some small changes.

Future plans

• Prepare the document that describes how to develop GatlingOperator using a dev container.
• Utilize utilize buildx for creating builds that support multiple platforms.

References

• Dockerfile reference | Docker Documentation

Notes

• I'm using keychain to forward the ssh-agent from my Mac to a dev container.
  • Funtoo Keychain Project - Funtoo
• Using Rosetta for amd emulation can result in slower processing, causing kube-apiserver to fail to start, and tests may not pass.
  • kube-apiserver failing to start on slow hardware kubernetes/kubernetes#72163
• You can use dev container without VSCode.

  # 1. Build the container image.
  $ docker build -f Dockerfile.dev -t gatling-operator-dev-container .
  # 2. Create and login an dev container
  $ docker run \
      --name=gatling-operator-dev-container  \
      --hostname=gatling-operator-dev-container \
      --network=host \
      --mount type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock \
      --mount type=bind,src=.,dst=/workspace \
      --env IN_DEV_CONTAINER="true" \
      -ti gatling-operator-dev-container
  # 3. If you exited, login to dev container again.
  $ docker exec -ti gatling-operator-dev-container bash
  

Checklist

• Tests have been added (if applicable, ie. when operator codes are added or modified)
• Relevant docs have been added or modified (if applicable, ie. when new features are added or current features are modified)

Relevant issue #88

[gold-kou]

I checked that some make commands work correctly.

LGTM

[itiB]

There is no problem with cp command running in the dev container, but I'm not happy if it runs locally.
Can you make if depending on whether it's in the dev container?

i think, dev container can set some environment variables from devcontainer.json.
ex. Create some check variable like IN_DEV_CONTAINER and check it.
https://code.visualstudio.com/remote/advancedcontainers/environment-variables

[R-HNF]

@itiB
I added IN_DEV_CONTAINER to check whether it's in the dev container.
Thank you!

[R-HNF]

cp command creates a .kube directory under the existing .kube directory, so I changed it to use kind get kubeconfig.

[itiB]

Looks well:+1:
I make some suggestion comment.

[R-HNF]

It's necessary to control kind clusters on the host.

[R-HNF]

restoring the backed-up kubeconfig.

[R-HNF]

make it available for use in other architectures as well.

[R-HNF]

@itiB
Please confirm that I have added how to use the dev container without using VSCode. Thanks:+1: