WIP: Extend GHA with a YAML/JSON linter

Signed-off-by: Jonathan Dowland <[email protected]>

.github/workflows/image-workflow-template.yml

@@ -8,6 +8,16 @@ on:
 env:
   LANG: en_US.UTF-8
 jobs:
+  validateYAML:
+    name: Validate YAML and JSON files touched by commit
+    timeout-minutes: 60
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - name: Find YAML and JSON files and verify their syntax
+        run: ./tools/lint.sh
   openjdkci:
     name: OpenJDK S2I Build and Test
     timeout-minutes: 60

tools/lint.sh

@@ -0,0 +1,23 @@
+ret=0
+
+# XXX this will only work for one commit PRs. Need to diff against the
+# merge base
+git diff-tree --no-commit-id --name-only HEAD -r |\
+while read f; do
+  case "${f##*.}" in
+    yaml)
+        # XXX we could use yamllint but it's too noisy for now
+        yq < "$f" >/dev/null || {
+            echo "$f is not valid YAML"
+            ret=1
+        }
+        ;;
+    json)
+        jq < "$f" >/dev/null || {
+            echo "$f is not valid JSON";
+            ret=1
+        }
+        ;;
+  esac
+done
+exit $ret