add linkcheck

TEMPLATE_CHANGES.md

@@ -18,6 +18,8 @@ be copied over manually if desired.
 - Refactored the template to follow the recommendations in APE 17:
   https://github.com/astropy/astropy-APEs/blob/master/APE17.rst [#438]
 
+- Added cron job for RST link checking [#482]
+
 2.1 (unreleased)
 ----------------
 

{{ cookiecutter.package_name }}/.travis.yml

@@ -127,6 +127,17 @@ matrix:
           stage: Initial tests
           env: TOXENV=codestyle
 
+        # Run documentation link check in a cron job.
+        - language: python
+          python: 3.8
+          name: Documentation link check
+          stage: Cron tests
+          env: TOXENV=linkcheck
+          addons:
+              apt:
+                  packages:
+                      - graphviz
+
     allow_failures:
         # Do a PEP8 test with flake8
         # (do allow to fail unless your code completely compliant)
@@ -136,6 +147,7 @@ matrix:
         #   stage: Initial tests
         #   env: TOXENV=codestyle
 
+
 before_install:
     # Create a coverage.xml for use by coveralls or codecov
     - if [[ $TOXENV == *-cov ]]; then

{{ cookiecutter.package_name }}/docs/conf.py

@@ -169,6 +169,15 @@
 # -- Resolving issue number to links in changelog -----------------------------
 github_issues_url = 'https://github.com/{0}/issues/'.format(setup_cfg['github_project'])
 
+
+# -- Options for linkcheck output -------------------------------------------
+linkcheck_retry = 5
+linkcheck_ignore = [
+    r'https://github\.com/{{ cookiecutter.github_project }}/(?:issues|pull)/\d+',
+]
+linkcheck_timeout = 180
+linkcheck_anchors = False
+
 # -- Turn on nitpicky mode for sphinx (to warn about references not found) ----
 #
 # nitpicky = True