Check upstream image every 6h.

It gets pushed last and shows up as the first item in docker hub.

.dockerignore

@@ -0,0 +1,2 @@
+ci/
+README.md

Dockerfile

@@ -1,6 +1,7 @@
 FROM moby/buildkit
 
 COPY entrypoint.sh /usr/local/bin/entrypoint.sh
+COPY entrypoint.sh /usr/local/bin/build
 ENTRYPOINT [ "entrypoint.sh" ]
 
 

README.md

@@ -0,0 +1,14 @@
+# concourse-buildkit
+
+A docker image to build multiarch images on [concourse](https://concourse-ci.org).
+
+## parameters
+
+- dest: Required. The output path for the oci image.
+- platform: Optional. A comma seperated list of target platforms, default: current platform
+- context: The context with which to build.
+- manual: Optional. Don't use params and instead supply all arguments via the command line, default: `false`
+
+## Example
+
+To view a simple invocation just look at [pipeline.yml](ci/pipeline.yml).

ci/pipeline.yml

@@ -0,0 +1,68 @@
+---
+resources:
+- name: source
+  type: git
+  source:
+    uri: https://gitea.redxef.at/redxef/concourse-buildkit
+    branch: master
+    fetch_tags: true
+- name: upstream-image
+  type: registry-image
+  check_every: 6h
+  source:
+    repository: moby/buildkit
+
+jobs:
+- name: build-push
+  plan:
+  - get: source
+    trigger: true
+  - get: upstream-image
+    trigger: true
+  - task: compute-docker-tags
+    config:
+      platform: linux
+      image_resource:
+        type: registry-image
+        source:
+          repository: alpine/git
+      inputs:
+      - name: source
+        path: .
+      outputs:
+      - name: docker-tags
+      run:
+        path: sh
+        args:
+        - -c
+        - |
+          #!/usr/bin/env sh
+          git rev-parse --short HEAD > docker-tags/tags.txt
+          git show-ref --tags | \
+              sed -n "/$(git rev-parse HEAD)/ s|$(git rev-parse HEAD).refs/tags/||gp" \
+              >> docker-tags/tags.txt
+  - task: build
+    privileged: true
+    config:
+      platform: linux
+      image_resource:
+        type: registry-image
+        source:
+          repository: redxef/concourse-buildkit
+          tag: v0.2.1
+      inputs:
+      - name: source
+        path: .
+      - name: docker-tags
+      params:
+        username: ((docker.username))
+        password: ((docker.password))
+        repository: docker.io/redxef/concourse-buildkit
+        tag: latest
+        additional_tags: docker-tags/tags.txt
+        push: true
+        platform: aarch64,arm,ppc64le,s390x,x86_64
+        context: .
+        manual: false
+      run:
+        path: build

entrypoint.sh

@@ -1,24 +1,47 @@
 #!/usr/bin/env sh
 
-DOCKER_LOGIN_FILE_TMPL='{
+fail() {
-    "auths": {
+    echo "Error:" "$@" 1>&2
-        "{{REGISTRY_URL}}": {
+    exit 1
-            "auth": "{{BASE64_UNAME_PW}}"
-        }
-    }
-}'
-
-docker_login() {
-    # TODO: detect registry url
-    mkdir -p "$HOME/.docker"
-    echo "$DOCKER_LOGIN_FILE_TMPL" | \
-        sed -e "s|{{BASE64_UNAME_PW}}|$(printf '%s:%s' "$username" "$password" | base64)|g" \
-            -e "s|{{REGISTRY_URL}}|https://index.docker.io/v1/|g" \
-        > "$HOME/.docker/config.json"
 }
 
-if [ -n "$username" ]; then
+echo_and_run() {
-    docker_login
+    echo "$@"
+    "$@"
+}
+
+plain() {
+    buildctl-daemonless.sh "$@"
+}
+
+build() {
+    if [ -z "$dest" ]; then
+        fail "missing argument: dest"
+    fi
+    if [ -z "$context" ]; then
+        context=.
+    fi
+    if [ -z "$platform" ]; then
+        platform=""
+    else
+        platform="--opt platform=$platform"
+    fi
+
+    echo_and_run buildctl-daemonless.sh \
+        build \
+        --frontend dockerfile.v0 \
+        --local context="$context" \
+        --local dockerfile="$context" \
+        $platform \
+        --output type=oci,dest="$dest"
+}
+
+if [ -z "$manual" ]; then
+    manual=false
 fi
 
-buildctl-daemonless.sh "$@"
+if "$manual"; then
+    plain "$@"
+else
+    build
+fi