Image Shas different for consecutive builds with `docker.#Dockerfile`

[bmritz]

What is the issue?

When building a docker image from a dockerfile to push to a registry, I'd expect the image sha of the image built with each dagger pipeline execution to be the same from execution to execution if nothing changes with the context or the Dockerfile. It appears that I instead sometimes see a unique sha for each image created by each execution of the same pipeline.

Log output

This is the log from the running the same command over & over with the same inputs. You can see that sometimes it will generate an image with the same sha256 that starts with 87 but other times (the very last execution for example) it generates an image with a different sha256.

britz:~/myprojects/minimal-example$dagger-cue version
dagger 0.2.232 (cbcb5061e) darwin/amd64

britz:~/myprojects/minimal-example$dagger-cue --log-format plain do loadDocker
1:56PM INFO  actions.loadDocker._defaultImage._pull | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | computing
1:56PM INFO  actions.source | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | completed    duration=0s
1:56PM INFO  actions.source | completed    duration=0s
1:56PM INFO  actions.buildDocker._build | computing
1:56PM INFO  actions.buildDocker._build | completed    duration=200ms
1:56PM INFO  actions.loadDocker._export | computing
1:56PM INFO  actions.loadDocker._defaultImage._pull | completed    duration=300ms
1:56PM INFO  actions.loadDocker._export | completed    duration=200ms
1:56PM INFO  actions.loadDocker._exec | computing
1:56PM INFO  actions.loadDocker._exec | #10 0.315 Loaded image: myimage:latest
1:56PM INFO  actions.loadDocker._exec | completed    duration=400ms
Field    Value
imageID  "sha256:8728791cc93948f08a704d294f6879f3cbf24b5baddbf80cb4d037bc930c505a"
britz:~/myprojects/minimal-example$dagger-cue --log-format plain do loadDocker
1:56PM INFO  actions.loadDocker._defaultImage._pull | computing
1:56PM INFO  actions.source | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | completed    duration=0s
1:56PM INFO  actions.source | completed    duration=0s
1:56PM INFO  actions.buildDocker._build | computing
1:56PM INFO  actions.buildDocker._build | completed    duration=200ms
1:56PM INFO  actions.loadDocker._export | computing
1:56PM INFO  actions.loadDocker._defaultImage._pull | completed    duration=300ms
1:56PM INFO  actions.loadDocker._export | completed    duration=300ms
1:56PM INFO  actions.loadDocker._exec | computing
1:56PM INFO  actions.loadDocker._exec | completed    duration=300ms
1:56PM INFO  actions.loadDocker._exec | #10 0.276 Loaded image: myimage:latest
Field    Value
imageID  "sha256:8728791cc93948f08a704d294f6879f3cbf24b5baddbf80cb4d037bc930c505a"
britz:~/myprojects/minimal-example$dagger-cue --log-format plain do loadDocker
1:56PM INFO  actions.loadDocker._defaultImage._pull | computing
1:56PM INFO  actions.source | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | computing
1:56PM INFO  client.network."unix:///var/run/docker.sock" | completed    duration=0s
1:56PM INFO  actions.source | completed    duration=0s
1:56PM INFO  actions.buildDocker._build | computing
1:56PM INFO  actions.buildDocker._build | completed    duration=200ms
1:56PM INFO  actions.loadDocker._export | computing
1:56PM INFO  actions.loadDocker._defaultImage._pull | completed    duration=300ms
1:56PM INFO  actions.loadDocker._export | completed    duration=300ms
1:56PM INFO  actions.loadDocker._exec | computing
1:56PM INFO  actions.loadDocker._exec | completed    duration=300ms
1:56PM INFO  actions.loadDocker._exec | #10 0.268 The image myimage:latest already exists, renaming the old one with ID sha256:8728791cc93948f08a704d294f6879f3cbf24b5baddbf80cb4d037bc930c505a to empty string
1:56PM INFO  actions.loadDocker._exec | #10 0.269 Loaded image: myimage:latest
Field    Value
imageID  "sha256:aa74e70707cdbbdf90d1e860a4fbb9b8e140d2175e15390178c551891490bcfe"

Steps to reproduce

dagger.cue

package minimal

import (
	"dagger.io/dagger"
	"universe.dagger.io/docker/cli"
	"dagger.io/dagger/core"
	"universe.dagger.io/docker"
)
dagger.#Plan & {
	// client: filesystem: ".": read: contents: dagger.#FS
    client: network: "unix:///var/run/docker.sock": connect: dagger.#Socket
	actions: {
		// Load the todoapp source code 
		source: core.#Source & {
			path: "."
			exclude: [
				"build",
				"*.cue",
				"*.md",
				".git",
				"cue.mod",
			]
		}
		buildDocker: docker.#Dockerfile & {
			// https://docs.dagger.io/sdk/cue/966156/docker#dockerdockerfile
    		source: actions.source.output
		}
        loadDocker: cli.#Load & {
            image: buildDocker.output
            host:  client.network."unix:///var/run/docker.sock".connect
            tag:   "myimage"
        }
	}
}

Dockerfile

FROM busybox:latest

ENV THIS=1

Run dagger-cue --log-format plain do loadDocker

Dagger version

dagger 0.2.232 (cbcb5061e) darwin/amd64

OS version

MacOS