markdown linter

.gitignore

@@ -24,3 +24,6 @@ Dockerfile.cross
 *.swp
 *.swo
 *~
+
+#macOS
+.DS_Store

Makefile

@@ -1,4 +1,6 @@
-
+# You can use podman or docker as a container engine. Notice that there are some options that might be only valid for one of them.
+ENGINE ?= docker
+IMAGE_NAME=kube-compare
 
 .PHONY: build
 build:
@@ -7,3 +9,22 @@ build:
 .PHONY: test
 test:
 	go test --race ./pkg/*
+
+# markdownlint rules, following: https://github.com/openshift/enhancements/blob/master/Makefile
+.PHONY: markdownlint-image
+markdownlint-image:  ## Build local container markdownlint-image
+	$(ENGINE) image build -f ./hack/markdownlint.Dockerfile --tag $(IMAGE_NAME)-markdownlint:latest ./hack
+
+.PHONY: markdownlint-image-clean
+markdownlint-image-clean:  ## Remove locally cached markdownlint-image
+	$(ENGINE) image rm $(IMAGE_NAME)-markdownlint:latest
+
+# markdownlint main
+markdownlint: markdownlint-image  ## run the markdown linter
+	$(ENGINE) run \
+		--rm=true \
+		--env RUN_LOCAL=true \
+		--env VALIDATE_MARKDOWN=true \
+		--env PULL_BASE_SHA=$(PULL_BASE_SHA) \
+		-v $$(pwd):/workdir:Z \
+		$(IMAGE_NAME)-markdownlint:latest

hack/markdownlint-install.sh

@@ -0,0 +1,19 @@
+#!/bin/bash -xe
+# Following example of: https://github.com/openshift/enhancements/blob/master/hack/install-markdownlint.sh
+
+cat /etc/redhat-release || echo "No /etc/redhat-release"
+
+if grep -q 'Red Hat Enterprise Linux' /etc/redhat-release; then
+    # install the config file for the RPM repository with node 14
+    # steps taken from https://rpm.nodesource.com/setup_14.x
+    yum module disable -y nodejs
+    curl -sL -o '/tmp/nodesource.rpm' 'https://rpm.nodesource.com/pub_14.x/el/8/x86_64/nodesource-release-el8-1.noarch.rpm'
+    rpm -i --nosignature --force /tmp/nodesource.rpm
+    yum -y install nodejs
+else
+    # Fedora has a module we can use
+    dnf -y module enable nodejs:16
+    dnf -y install nodejs
+fi
+
+npm install -g markdownlint@v0.25.1 markdownlint-cli2@v0.4.0

hack/markdownlint.Dockerfile

@@ -0,0 +1,7 @@
+# Following example of: https://github.com/openshift/enhancements/blob/master/hack/Dockerfile.markdownlint
+FROM registry.access.redhat.com/ubi9/ubi:latest
+WORKDIR /workdir
+RUN dnf install -y git golang
+COPY markdownlint-install.sh /tmp
+RUN /tmp/markdownlint-install.sh
+ENTRYPOINT /workdir/hack/markdownlint.sh

hack/markdownlint.sh

@@ -0,0 +1,20 @@
+#!/bin/bash -ex
+# Following example of: https://github.com/openshift/enhancements/blob/master/hack/markdownlint.sh
+
+# trap errors, including the exit code from the command failed
+trap 'handle_exit $?' EXIT
+
+function handle_exit {
+    # If the exit code we were given indicates an error, suggest that
+    # the author run the linter locally.
+    if [ "$1" != "0" ]; then
+    cat - <<EOF
+
+To run the linter on a Linux system with podman, run "make markdownlint"
+after committing your changes locally.
+
+EOF
+    fi
+}
+
+markdownlint-cli2 '**/*.md' !'vendor/**/*.md'