From 8a9ab11908b9878347e4c4e0582bc159fc80fc2b Mon Sep 17 00:00:00 2001
From: Matthew Thompson <matthew.thompson@nasa.gov>
Date: Thu, 23 Jun 2022 15:49:11 -0400
Subject: [PATCH] Add YAML Linter

---
 .github/workflows/changelog-enforcer.yml      |  2 +-
 .github/workflows/validate_yaml_files.yml     | 24 +++++++++++++++
 .yamllint.yml                                 | 29 +++++++++++++++++++
 CHANGELOG.md                                  |  2 ++
 .../test_cases/case11/extdata.yaml            |  2 +-
 .../test_cases/case23/extdata.yaml            |  2 +-
 6 files changed, 58 insertions(+), 3 deletions(-)
 create mode 100644 .github/workflows/validate_yaml_files.yml
 create mode 100644 .yamllint.yml

diff --git a/.github/workflows/changelog-enforcer.yml b/.github/workflows/changelog-enforcer.yml
index 1e9cb2979097..cd31258b2684 100644
--- a/.github/workflows/changelog-enforcer.yml
+++ b/.github/workflows/changelog-enforcer.yml
@@ -4,7 +4,7 @@ on:
       types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
 
 jobs:
-  # Enforces the update of a changelog file on every pull request 
+  # Enforces the update of a changelog file on every pull request
   changelog:
     runs-on: ubuntu-latest
     steps:
diff --git a/.github/workflows/validate_yaml_files.yml b/.github/workflows/validate_yaml_files.yml
new file mode 100644
index 000000000000..b87f59d99d05
--- /dev/null
+++ b/.github/workflows/validate_yaml_files.yml
@@ -0,0 +1,24 @@
+---
+name: Yaml Lint
+
+on:
+  pull_request:
+      types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
+jobs:
+  validate-YAML:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - id: yaml-lint
+        name: yaml-lint
+        uses: ibiqlik/action-yamllint@v3
+        with:
+          no_warnings: true
+          format: colored
+          config_file: .yamllint.yml
+
+      - uses: actions/upload-artifact@v2
+        if: always()
+        with:
+          name: yamllint-logfile
+          path: ${{ steps.yaml-lint.outputs.logfile }}
diff --git a/.yamllint.yml b/.yamllint.yml
new file mode 100644
index 000000000000..83f5340c7fdf
--- /dev/null
+++ b/.yamllint.yml
@@ -0,0 +1,29 @@
+---
+
+extends: default
+
+rules:
+  braces:
+    level: warning
+    max-spaces-inside: 1
+  brackets:
+    level: warning
+    max-spaces-inside: 1
+  colons:
+    level: warning
+  commas:
+    level: warning
+  comments: disable
+  comments-indentation: disable
+  document-start: disable
+  empty-lines:
+    level: warning
+  hyphens:
+    level: warning
+  indentation:
+    level: warning
+    indent-sequences: consistent
+  line-length:
+    level: warning
+    allow-non-breakable-inline-mappings: true
+  truthy: disable
diff --git a/CHANGELOG.md b/CHANGELOG.md
index f06bf2c7c10a..ebf770d624c5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,6 +28,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added monotonic regridding option
 - Make availalbe to History and ExtData2G all supported regridding methods
 - Add test cases for ExtData
+- Add YAML validator GitHub Action
+  - This action makes sure all YAML files are valid (to a relaxed standard)
 
 ### Changed
 
diff --git a/Tests/ExtData_Testing_Framework/test_cases/case11/extdata.yaml b/Tests/ExtData_Testing_Framework/test_cases/case11/extdata.yaml
index f5641f693d84..6738280d70a4 100644
--- a/Tests/ExtData_Testing_Framework/test_cases/case11/extdata.yaml
+++ b/Tests/ExtData_Testing_Framework/test_cases/case11/extdata.yaml
@@ -1,4 +1,4 @@
 Collections:
    fstream1: {template: "case1.%y4%m2.nc4", valid_range: "2006-01-01/2007-12-31" }
 Exports:
-   VAR2D: {variable: VAR2D, collection: fstream1, sample: {extrapolation: clim}} 
+   VAR2D: {variable: VAR2D, collection: fstream1, sample: {extrapolation: clim}}
diff --git a/Tests/ExtData_Testing_Framework/test_cases/case23/extdata.yaml b/Tests/ExtData_Testing_Framework/test_cases/case23/extdata.yaml
index 62007858b755..49fa281346d1 100644
--- a/Tests/ExtData_Testing_Framework/test_cases/case23/extdata.yaml
+++ b/Tests/ExtData_Testing_Framework/test_cases/case23/extdata.yaml
@@ -6,6 +6,6 @@ Samplings:
    extrapolation: clim
    source_time: "2016-01-01/2016-12-31"
 Exports:
-   VAR2D: 
+   VAR2D:
        - {starting: 1970-01-01, variable: VAR2D, collection: fstream1, sample: S1}
        - {starting: 2020-01-01, variable: VAR2D, collection: fstream2}