add step to verify docs on area/documentation PRs

Signed-off-by: Sebastian Malton <sebastian@malton.name>

.azure-pipelines.yml

@@ -162,3 +162,27 @@ jobs:
         condition: "and(succeeded(), startsWith(variables['Build.SourceBranch'], 'refs/tags/'))"
         env:
           NPM_TOKEN: $(NPM_TOKEN)
+---
+variables:
+  YARN_CACHE_FOLDER: $(Pipeline.Workspace)/.yarn
+pr:
+  - master
+  - releases/*
+trigger:
+  branches:
+    include:
+    - '*'
+  tags:
+    include:
+    - "area/documentation"
+jobs:
+  - job: Check-Docs
+    pool:
+      vmImage: ubuntu-16.04
+    strategy:
+      matrix:
+        node_12.x:
+          node_version: 12.x
+    steps:
+      - displayName: Verify that docs build
+        script: yarn run mkdocs-verify

.gitignore

@@ -16,3 +16,4 @@ types/extension-api.d.ts
 types/extension-renderer-api.d.ts
 extensions/*/dist
 docs/extensions/api
+site/

package.json

@@ -40,6 +40,7 @@
     "lint": "yarn run eslint $@ --ext js,ts,tsx --max-warnings=0 src/ integration/ __mocks__/ build/ extensions/",
     "lint:fix": "yarn run lint --fix",
     "mkdocs-serve-local": "docker build -t mkdocs-serve-local:latest mkdocs/ && docker run --rm -it -p 8000:8000 -v ${PWD}:/docs mkdocs-serve-local:latest",
+    "mkdocs-verify": "docker build -t mkdocs-serve-local:latest mkdocs/ && docker run --rm -it -p 8000:8000 -v ${PWD}:/docs mkdocs-serve-local:latest build --strict",
     "typedocs-extensions-api": "yarn run typedoc --ignoreCompilerErrors --readme docs/extensions/typedoc-readme.md.tpl --name @k8slens/extensions --out docs/extensions/api --mode library --excludePrivate --hideBreadcrumbs --includes src/ src/extensions/extension-api.ts"
   },
   "config": {