adds testing images for dual-stream image-mode

These images will be built by the CI system and injected into the e2e
tests so that we can test image-mode on dual-stream.

Author: cheesesashimi

Containerfile.helpers-ci

@@ -1,4 +1,4 @@
-FROM registry.ci.openshift.org/ocp/builder:rhel-9-golang-1.22-builder-multi-openshift-4.18 AS builder
+FROM registry.ci.openshift.org/ocp/builder:rhel-9-golang-1.24-openshift-4.21 AS builder
 ENV GOCACHE="/go/.cache" \
     GOMODCACHE="/go/pkg/mod"
 WORKDIR /go/src/github.com/openshift/machine-config-operator
@@ -7,5 +7,5 @@ RUN --mount=type=cache,target=/go/.cache,z \
     --mount=type=cache,target=/go/pkg/mod,z \
     make install-helpers DESTDIR=/helpers
 
-FROM registry.ci.openshift.org/ocp/builder:rhel-9-enterprise-base-multi-openshift-4.18 AS final
+FROM registry.ci.openshift.org/ocp/4.21:base-rhel9 AS final
 COPY --from=builder /helpers/usr/bin /usr/bin

Dockerfile.rhel7

@@ -45,7 +45,8 @@ RUN --mount=type=cache,target=/var/cache/dnf,z \
     # Create the build user which will be used for doing OS image builds. We
     # use the username "build" and the uid 1000 since this matches what is in
     # the official Buildah image.
-    useradd --uid 1000 build
+    # Conditional checks if "build" user does not exist before adding user.
+    if ! id -u "build" >/dev/null 2>&1; then useradd --uid 1000 build; fi
 # Copy the binaries *after* we install nmstate so we don't invalidate our cache for local builds.
 COPY --from=rhel9-builder /go/src/github.com/openshift/machine-config-operator/instroot-rhel9.tar /tmp/instroot-rhel9.tar
 RUN cd / && tar xf /tmp/instroot-rhel9.tar && rm -f /tmp/instroot-rhel9.tar

Makefile

@@ -10,6 +10,11 @@ PREFIX ?= /usr
 GO111MODULE?=on
 PROJECT_DIR := $(shell dirname $(abspath $(lastword $(MAKEFILE_LIST))))
 
+# Find all of the test OS image Containerfiles so they can be built.
+CUSTOM_OS_TEST_IMAGE_DIR := $(E2E_ROOT_DIR)/custom-os-images
+CUSTOM_OS_TEST_CONTAINERFILES := $(wildcard $(CUSTOM_OS_TEST_IMAGE_DIR)/Containerfile.*)
+CUSTOM_OS_TEST_IMAGE_NAMES := $(patsubst $(CUSTOM_OS_TEST_IMAGE_DIR)/Containerfile.%,%,$(CUSTOM_OS_TEST_CONTAINERFILES))
+
 # Copied from coreos-assembler
 GOARCH := $(shell uname -m)
 ifeq ($(GOARCH),x86_64)
@@ -30,7 +35,7 @@ GOTAGS = "containers_image_openpgp exclude_graphdriver_devicemapper exclude_grap
 
 all: binaries
 
-.PHONY: clean test test-unit test-e2e verify update update-amis install-tools
+.PHONY: clean test test-unit test-e2e verify update install-tools custom-os-images
 
 # Remove build artifaces
 # Example:
@@ -57,6 +62,28 @@ _verify-e2e-%:
 image:
 	hack/build-image
 
+# Define a template rule to build a specific test image.
+# Accepts the image name suffix (e.g., "rhel-coreos-9") as the
+# sole argument.
+#
+# The images will be produced with the names like localhost/custom-os-image:rhel-coreos-9.
+define custom_os_image_build_template =
+.PHONY: custom-os-image-$(1)
+custom-os-image-$(1):
+	podman build \
+		-f $(CUSTOM_OS_TEST_IMAGE_DIR)/Containerfile.$(1) \
+		-t localhost/custom-os-image:$(1) \
+		$(CUSTOM_OS_TEST_IMAGE_DIR)
+endef
+
+# Create a target for each detected test image (e.g., rhel-coreos-9).
+$(foreach C, $(CUSTOM_OS_TEST_IMAGE_NAMES), $(eval $(call custom_os_image_build_template,$(C))))
+
+# Target to build all detected custom OS test images. This is mostly for use by
+# developers on their workstations since they must be explicitly declared in
+# OpenShift CI.
+custom-os-images: $(patsubst %,custom-os-image-%,$(CUSTOM_OS_TEST_IMAGE_NAMES))
+
 # Run tests
 test: test-unit test-e2e
 

test/custom-os-images/Containerfile.rhel-coreos-10

@@ -0,0 +1,15 @@
+FROM registry.ci.openshift.org/ocp/4.21:rhel-coreos-10 AS base
+
+FROM quay.io/centos/centos:stream10 AS epel
+WORKDIR /etc/yum.repos.d
+RUN dnf install -y --setopt=keepcache=True epel-release && \
+    curl -LO https://pkgs.tailscale.com/stable/rhel/10/tailscale.repo && \
+    sed -i 's/\$stream/10-stream/g' /etc/yum.repos.d/centos*.repo && \
+    sed -i 's/EPEL\-\$releasever_major/EPEL-10/g' /etc/yum.repos.d/epel*.repo && \
+    sed -i -E 's/\$\{releasever_minor\:\+\-z\}//g' /etc/yum.repos.d/epel*.repo
+
+FROM base AS final
+COPY --from=epel /etc/yum.repos.d /etc/yum.repos.d
+COPY --from=epel /etc/pki/rpm-gpg/RPM-GPG-KEY-* /etc/pki/rpm-gpg/
+RUN rpm-ostree install ripgrep yq tailscale && \
+    ostree container commit

test/custom-os-images/Containerfile.rhel-coreos-9

@@ -0,0 +1,13 @@
+FROM registry.ci.openshift.org/ocp/4.21:rhel-coreos AS base
+
+FROM quay.io/centos/centos:stream9 AS epel
+WORKDIR /etc/yum.repos.d
+RUN dnf install -y epel-release && \
+    curl -LO https://pkgs.tailscale.com/stable/rhel/9/tailscale.repo && \
+    sed -i 's/\$stream/9-stream/g' /etc/yum.repos.d/centos*.repo
+
+FROM base AS final
+COPY --from=epel /etc/yum.repos.d /etc/yum.repos.d
+COPY --from=epel /etc/pki/rpm-gpg/RPM-GPG-KEY-* /etc/pki/rpm-gpg/
+RUN rpm-ostree install ripgrep yq tailscale && \
+    ostree container commit

test/custom-os-images/README.md

@@ -0,0 +1,9 @@
+# custom-os-images
+
+This directory contains two Containerfiles,
+`Containerfile.rhel-coreos-9` and
+`Containerfile.rhel-coreos-10`, respectively. These images are
+intended for testing Image Mode OpenShift and are built / managed by the CI
+system.
+
+That said, there is a Makefile target, `make custom-os-test-images` that can be used locally by developers to validate that the images build without issue.