docker_image build image even if file context and dockerfile doesn't change about terraform-provider-docker

[samuelcortinhas]

I've also come across this bug. Our use case was to build an image from a dockerfile in a folder src/example and push it to an AWS ECR repository. We wanted to only rebuild/push image when there were changes to the code in src/example. However, even with the triggers hash is the same, the docker_image is being rebuilt every time.

resource "docker_registry_image" "registry_image" {
  name = docker_image.image.name
}

resource "docker_image" "image" {
  name = "${aws_ecr_repository.repository.repository_url}:latest"

  build {
    context = "${path.module}/src/example"
  }
  triggers = {
    dir_sha1 = sha1(join("", [for f in fileset(path.module, "src/example/**") : filesha1(f)]))
  }
}

Our solution was to rollback to version 2.25.0 of kreuzwerker/docker. (note the above configuration needs changing for this version).

[asmisha]

In my case the build is triggered even if the content has not changed. I suspect that it's auth_config that causes the rebuild due to changing credentials.

[vnghia]

I found that the build will be retriggered if the content of (file, subfolder, etc) your context folder change, which makes sense because the provider does not know which file in the context folder will be used (e.g COPY or ADD could copy them into the image) while building the Dockerfile.

[pspot2]

I guess quite a few of us are currently sitting on 2.25.0 because of this.

See also #555