makefiles/
----------
  o Adding more lint target logic.
  o Copy in virtualenv.mk from voltha-docs to support dependency
    based virtualenv installations.

*/*.yaml
--------
  o Misc yamllint cleanups.

Makefile
--------
  o Prune inlined logic since replaced by library makefile logic.
  o Replaced explicit pyenv installation with dependency driven
    so venv will only require installation once per target run.
  o Library make clean/sterile targets handle cleanup.

Change-Id: Ie2ce0ebc01b07c0004a5904c2641c394e46d5044
diff --git a/makefiles/lint/yaml/.yamllint b/makefiles/lint/yaml/.yamllint
new file mode 100644
index 0000000..6a4fc1e
--- /dev/null
+++ b/makefiles/lint/yaml/.yamllint
@@ -0,0 +1,45 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022 Open Networking Foundation (ONF) and the ONF Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-FileCopyrightText: 2022 Open Networking Foundation (ONF) and the ONF Contributors
+# SPDX-License-Identifier: Apache-2.0
+# -----------------------------------------------------------------------
+---
+
+yaml-files:
+  - '*.yaml'
+  - '*.yml'
+  - '.yamllint'
+
+rules:
+  document-start: disable
+  line-length:
+    max: 160
+
+# -----------------------------------------------------------------------
+# .. seealso: https://gerrit.opencord.org/plugins/gitiles/helm-repo-tools/+/refs/heads/master/yamllint.conf
+# -----------------------------------------------------------------------
+#
+# extends: default
+#
+#rules:
+#  empty-lines:
+#    max-end: 1
+#  line-length:
+#    max: 120
+#  braces:
+#    min-spaces-inside: 0
+#    max-spaces-inside: 1
diff --git a/makefiles/lint/yaml/python.mk b/makefiles/lint/yaml/python.mk
new file mode 100644
index 0000000..868d9b7
--- /dev/null
+++ b/makefiles/lint/yaml/python.mk
@@ -0,0 +1,41 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022 Open Networking Foundation (ONF) and the ONF Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-FileCopyrightText: 2022 Open Networking Foundation (ONF) and the ONF Contributors
+# SPDX-License-Identifier: Apache-2.0
+# -----------------------------------------------------------------------
+
+YAML_FILES ?= $(error YAML_FILES= is required)
+
+lint-yaml-dep = $(addsuffix ^lint-yaml,$(YAML_FILES))
+lint-yaml-src = $(firstword $(subst ^,$(space),$(1)))
+
+##-------------------##
+##---]  TARGETS  [---##
+##-------------------##
+.PHONY : lint-yaml
+lint   : lint-yaml
+
+lint-yaml: $(venv-activate)
+lint-yaml: $(lint-yaml-dep)
+
+$(lint-yaml-dep):
+	$(vst-env) && yamllint -s $(call lint-yaml-src,$@)
+
+help::
+	@echo "  lint-yaml            Syntax check yaml sources"
+
+# [EOF]
diff --git a/makefiles/lint/yaml/todo b/makefiles/lint/yaml/todo
new file mode 100644
index 0000000..8a9367b
--- /dev/null
+++ b/makefiles/lint/yaml/todo
@@ -0,0 +1,39 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022 Open Networking Foundation (ONF) and the ONF Contributors
+# -----------------------------------------------------------------------
+
+##-------------------##
+##---]  GLOBALS  [---##
+##-------------------##
+env-clean = /usr/bin/env --ignore-environment
+xargs-n1      := xargs -0 -t -n1 --no-run-if-empty
+
+yamllint      := $(env-clean) $(YAMLLINT)
+yamllint-args := -c .yamllint
+
+##-------------------##
+##---]  TARGETS  [---##
+##-------------------##
+lint : lint-yaml
+
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+lint-yaml:
+	$(HIDE)$(env-clean) find . -name '*.yaml' -type f -print0 \
+	    | $(xargs-n1) $(yamllint) $(yamllint-args)
+
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+help:
+	@echo
+	@echo "USAGE: $(MAKE)"
+	@echo "  lint        perform syntax checks on source"
+	@echo "  test        perform syntax checks on source"
+	@echo "  pre-check   Verify tools and deps are available for testing"
+	@echo
+	@echo "[LINT]"
+	@echo "  lint-json   Syntax check .json sources"
+	@echo "  lint-yaml   Syntax check .yaml sources"
+	@echo
+# [EOF]
diff --git a/makefiles/lint/yaml/urls b/makefiles/lint/yaml/urls
new file mode 100644
index 0000000..8747658
--- /dev/null
+++ b/makefiles/lint/yaml/urls
@@ -0,0 +1,5 @@
+# -*- makefile -*-
+
+https://yamllint.readthedocs.io/en/stable/configuration.html
+
+# [EOF]
\ No newline at end of file
diff --git a/makefiles/lint/yaml/yamllint.helm b/makefiles/lint/yaml/yamllint.helm
new file mode 100644
index 0000000..6c7787b
--- /dev/null
+++ b/makefiles/lint/yaml/yamllint.helm
@@ -0,0 +1,32 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022 Open Networking Foundation (ONF) and the ONF Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-FileCopyrightText: 2022 Open Networking Foundation (ONF) and the ONF Contributors
+# SPDX-License-Identifier: Apache-2.0
+# -----------------------------------------------------------------------
+---
+# yamllint.conf
+
+extends: default
+
+rules:
+  empty-lines:
+    max-end: 1
+  line-length:
+    max: 120
+  braces:
+    min-spaces-inside: 0
+    max-spaces-inside: 1
diff --git a/makefiles/lint/yaml/yamllint.mk b/makefiles/lint/yaml/yamllint.mk
new file mode 100644
index 0000000..6782c74
--- /dev/null
+++ b/makefiles/lint/yaml/yamllint.mk
@@ -0,0 +1,56 @@
+# -*- makefile -*-
+# -----------------------------------------------------------------------
+# Copyright 2022 Open Networking Foundation (ONF) and the ONF Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-FileCopyrightText: 2022 Open Networking Foundation (ONF) and the ONF Contributors
+# SPDX-License-Identifier: Apache-2.0
+# -----------------------------------------------------------------------
+
+$(if $(DEBUG),$(warning ENTER))
+
+yamllint      := $(env-clean) yamllint
+
+## -------------------------------
+## Add requirement(s) for checking
+## -------------------------------
+# yamllint-cfg := .yamllint
+yamllint-cfg := yamllint.helm
+yamllint-conf = $(wildcard $(yamllint-cfg) $(MAKEDIR)/lint/yaml/$(yamllint-cfg))
+yamllint-args += $(addprefix --config-file$(space),$(yamllint-conf))
+
+# yamllint-args := --no-warnings
+# yamllint-args := --strict
+
+yamllint-find := find .
+yamllint-find += -name 'vendor' -prune
+yamllint-find += -o -name '*.yaml'
+yamllint-find += ! -name '\.\#*.yaml'
+yamllint-find += -type f
+yamllint-find += -print0
+
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+lint lint-yaml:
+	$(HIDE)$(env-clean) $(yamllint-find) \
+	    | xargs -0 --no-run-if-empty -t -n1 $(yamllint) $(yamllint-args)
+
+## -----------------------------------------------------------------------
+## -----------------------------------------------------------------------
+help::
+	@echo "  lint-yaml                     Syntax check yaml sources"
+
+$(if $(DEBUG),$(warning ENTER))
+
+# [EOF]