yamllint: Lint all the YAML files

For now, a list of YAML files' paths is hardcoded (even after
globbing) into Makefile.am. Moreover, Azure templates are not
checked at all until Azure triggered.

With this change, the list of YAMLs is populated automatically
on yamllinting.

Jinja templates are not parseable by a regular yaml module, to
skip such the YAML_TEMPLATE_FILES is utilized.

Fixes: https://pagure.io/freeipa/issue/8202
Signed-off-by: Stanislav Levin <slev@altlinux.org>
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>

Makefile.am

@@ -275,16 +275,33 @@ polint:
 rpmlint: freeipa.spec
 	rpmlint ./$<
 
-YAML_FILES = \
-	$(top_srcdir)/.lgtm.yml \
-	$(wildcard $(top_srcdir)/.*.yaml) \
-	$(wildcard $(top_srcdir)/ipatests/prci_definitions/*.yaml)
-
+# Try to load yml/yaml files via safe_load, which recognizes only standard
+# YAML tags and cannot construct an arbitrary Python object.
+# There are Jinja yaml templates, which differ from reqular ones. These
+# files should be placed on skip list (YAML_TEMPLATE_FILES), otherwise
+# safe_load fails.
 .PHONY: yamllint
-yamllint: $(YAML_FILES)
-	@for YAML in $^; do \
-		$(PYTHON) -c "import yaml; f = open('$${YAML}'); yaml.safe_load(f); f.close()" || exit 1; \
-	done
+yamllint:
+	YAML_TEMPLATE_FILES="\
+		$(top_srcdir)/ipatests/azure/templates/ipa-test-config-template.yaml \
+	"; \
+	echo "jinja template files:"; \
+	for YAML in $${YAML_TEMPLATE_FILES}; do \
+		echo $${YAML}; \
+		$(PYTHON) -c "import yaml; f = open('$${YAML}'); yaml.safe_load(f); f.close()" >/dev/null 2>&1 \
+		&& { echo Unexpected PASS of parsing yaml: $${YAML}. This file is a regular yaml.; exit 1; }; \
+	done; \
+	YAML_FILES=`find $(top_srcdir) \
+		\( -name '*.yaml' -o \
+		-name '*.yml' \) \
+		$$(printf '! -path %s ' $${YAML_TEMPLATE_FILES})`; \
+	echo -e "\nlint yaml files"; \
+	echo "-----------"; \
+	for YAML in $${YAML_FILES}; do \
+		echo $${YAML}; \
+		$(PYTHON) -c "import yaml; f = open('$${YAML}'); yaml.safe_load(f); f.close()" || { echo Your YAML file: $${YAML} has a wrong syntax or this is a Jinja template. In the latter clause, consider to add your YAML file to the YAML_TEMPLATE_FILES list in Makefile.am.; exit 1; } \
+	done; \
+	echo "-----------"
 
 # Run pylint for all python files. Finds all python files/packages, skips
 # folders rpmbuild, freeipa-* and dist. Skip (match, but don't print) .*,