refactor: build images from heroku/heroku:STACK-build images

Rather than try and emulate the work heroku is doing, use their upstream images as is. This simplifies the build process signficantly, and allows us to only layer the necessary on top of their images.

This was not previously possible due to missing arm64 support, which is introduced in the heroku-24 stack. Thus, this will fail for all other stacks.

.github/workflows/main.yml

@@ -25,8 +25,6 @@ jobs:
           - "true"
           - "false"
         heroku:
-          - 20
-          - 22
           - 24
 
     steps:
@@ -112,8 +110,6 @@ jobs:
           - buildpack-scala
           - buildpack-static
         heroku:
-          - 20
-          - 22
           - 24
 
     steps:

.github/workflows/release.yml

@@ -15,8 +15,6 @@ jobs:
       fail-fast: false
       matrix:
         heroku:
-          - 20
-          - 22
           - 24
 
     steps:

Dockerfile

@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:1
-ARG STACK_VERSION=20
+ARG STACK_VERSION=24
 
 FROM golang:1.23 AS builder
 RUN mkdir /src
@@ -9,35 +9,22 @@ WORKDIR /src
 ARG VERSION
 RUN go build -a -ldflags "-X main.Version=$VERSION" -o herokuish .
 
-FROM ubuntu:${STACK_VERSION}.04 AS base
-ARG STACK_VERSION=20
+FROM heroku/heroku:${STACK_VERSION}-build AS base
+ARG STACK_VERSION=24
 ARG TARGETARCH
 
-ADD https://raw.githubusercontent.com/heroku/stack-images/main/heroku-${STACK_VERSION}/setup.sh /tmp/setup-01.sh
-ADD https://raw.githubusercontent.com/heroku/stack-images/main/heroku-${STACK_VERSION}-build/setup.sh /tmp/setup-02.sh
-COPY bin/setup.sh /tmp/setup.sh
-RUN --mount=source=build-deps/${STACK_VERSION},target=/build  STACK_VERSION=${STACK_VERSION} TARGETARCH=${TARGETARCH} /tmp/setup.sh && \
-    rm -rf /tmp/setup.sh
-
 ENV STACK=heroku-$STACK_VERSION
 ENV DEBIAN_FRONTEND noninteractive
 LABEL com.gliderlabs.herokuish/stack=$STACK
 
-RUN apt-get update -qq \
-    && apt-get install --no-install-recommends -qq -y daemontools \
-    && cp /etc/ImageMagick-6/policy.xml /etc/ImageMagick-6/policy.xml.custom \
-    && apt-get  -y -o Dpkg::Options::=--force-confdef -o Dpkg::Options::=--force-confnew \
-    --allow-downgrades \
-    --allow-remove-essential \
-    --allow-change-held-packages \
-    dist-upgrade \
-    && mv /etc/ImageMagick-6/policy.xml.custom /etc/ImageMagick-6/policy.xml \
-    && apt-get clean \
-    && rm -rf /var/cache/apt/archives/* /var/lib/apt/lists/* /var/tmp/*
-
+USER root
+# for setuidgid
+COPY bin/apt-install /usr/local/bin/apt-install
+RUN apt-install daemontools
 COPY --from=builder /src/herokuish /bin/
 
-RUN /bin/herokuish buildpack install \
+RUN apt-install daemontools && \
+    /bin/herokuish buildpack install \
     && ln -s /bin/herokuish /build \
     && ln -s /bin/herokuish /start \
     && ln -s /bin/herokuish /exec \
@@ -54,3 +41,4 @@ RUN /bin/herokuish buildpack install \
 COPY include/default_user.bash /tmp/default_user.bash
 RUN bash /tmp/default_user.bash && rm -f /tmp/default_user.bash
 ENV BASH_BIN /usr/bin/bash
+USER herokuishuser

Makefile

@@ -14,7 +14,7 @@ SHELL := /bin/bash
 SYSTEM := $(shell sh -c 'uname -s 2>/dev/null')
 DOCKER_ARGS ?= "--pull"
 BUILDX ?= true
-STACK_VERSION ?= 20
+STACK_VERSION ?= 24
 
 shellcheck:
 ifneq ($(shell shellcheck --version > /dev/null 2>&1 ; echo $$?),0)
@@ -55,13 +55,11 @@ build: bindata.go
 	$(MAKE) build/deb/$(NAME)_$(VERSION)_all.deb
 
 build/docker:
-	$(MAKE) build/docker/20 STACK_VERSION=20
-	$(MAKE) build/docker/22 STACK_VERSION=22
 	$(MAKE) build/docker/24 STACK_VERSION=24
 
 build/docker/$(STACK_VERSION): bindata.go
 ifeq ($(BUILDX),true)
-ifeq ($(STACK_VERSION),20)
+ifeq ($(STACK_VERSION),24)
 	docker buildx build --no-cache ${DOCKER_ARGS} --pull --progress plain --platform linux/arm64/v8,linux/amd64 --build-arg STACK_VERSION=$(STACK_VERSION) --build-arg VERSION=$(VERSION) -t $(IMAGE_NAME):$(BUILD_TAG)-$(STACK_VERSION) -t $(IMAGE_NAME):latest-$(STACK_VERSION) -t $(IMAGE_NAME):$(BUILD_TAG) -t $(IMAGE_NAME):latest .
 else
 	docker buildx build --no-cache ${DOCKER_ARGS} --pull --progress plain --platform linux/arm64/v8,linux/amd64 --build-arg STACK_VERSION=$(STACK_VERSION) --build-arg VERSION=$(VERSION) -t $(IMAGE_NAME):$(BUILD_TAG)-$(STACK_VERSION) -t $(IMAGE_NAME):latest-$(STACK_VERSION) .
@@ -127,8 +125,6 @@ clean:
 	docker rmi herokuish:dev || true
 
 deps: bindata.go
-	docker pull heroku/heroku:20-build
-	docker pull heroku/heroku:22-build
 	docker pull heroku/heroku:24-build
 	cd / && go get -u github.com/progrium/basht/...
 	$(MAKE) bindata.go

README.md

@@ -8,7 +8,7 @@ A command line tool for emulating Heroku build and runtime tasks in containers.
 
 Herokuish is made for platform authors. The project consolidates and decouples Heroku compatibility logic (running buildpacks, parsing Procfile) and supporting workflow (importing/exporting slugs) from specific platform images like those in Dokku/Buildstep, Deis, Flynn, etc.
 
-The goal is to be the definitive, well maintained and heavily tested Heroku emulation utility shared by all. It is based on the [Heroku:20, Heroku:22, and Heroku:24 system images](https://github.com/heroku/stack-images). Together they form a toolkit for achieving Heroku compatibility.
+The goal is to be the definitive, well maintained and heavily tested Heroku emulation utility shared by all. It is based on the [Heroku:24 system image](https://github.com/heroku/stack-images). Together they form a toolkit for achieving Heroku compatibility.
 
 Herokuish is a community project and is in no way affiliated with Heroku.
 
@@ -208,7 +208,7 @@ $ docker run --rm -e TRACE=true -v /abs/app/path:/tmp/app gliderlabs/herokuish /
 You can also set a custom buildpack:
 
 ```shell
-docker run -e BUILDPACK_URL="https://github.com/custom/buildpack.git#with-a-branch" -e STACK=heroku-20 -e TRACE=true --rm -v ./:/tmp/app -it gliderlabs/herokuish /bin/herokuish test
+docker run -e BUILDPACK_URL="https://github.com/custom/buildpack.git#with-a-branch" -e STACK=heroku-24 -e TRACE=true --rm -v ./:/tmp/app -it gliderlabs/herokuish /bin/herokuish test
 ```
 
 Note that the underlying buildpacks will not trace their commands with `TRACE=true` is enabled. They need to independently set `set -x` in order to trace execution.

bin/apt-install

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+# apt-install - install packages using apt-get
+# Usage: apt-install package1 package2 package3 ...
+
+main() {
+    declare PACKAGES=("$@")
+
+    if [[ ${#PACKAGES[@]} -eq 0 ]]; then
+        echo "Usage: apt-install package1 package2 package3 ..."
+        exit 1
+    fi
+
+    DEBIAN_FRONTEND=noninteractive
+    apt-get update
+    apt-get -o Dpkg::Use-Pty=0 --no-install-recommends -y install "${PACKAGES[@]}"
+    apt-get clean
+    rm -rf /var/cache/apt/archives/* /var/lib/apt/lists/* /var/tmp/*
+}
+
+main "$@"