templates/swh-pipeline: Add stage to build sphinx documentation

If it exists a sphinx tox environment in the built project, it will
be executed to build sphinx documentation and check for errors.

Related to T3258

jobs/templates/includes/agent-docker-sphinx.groovy.j2

+agent {
+  docker {
+    reuseNode true
+    image 'swh-jenkins/{{sphinx_docker_image}}'
+    args '--mount type=volume,src=shared-jenkins-cachedir,dst=/home/jenkins/.cache'
+  }
+}

jobs/templates/swh-pipeline-diff.yaml

@@ -4,6 +4,7 @@
     project-type: pipeline
     docker_image: tox
     cypress_docker_image: cypress
+    sphinx_docker_image: sphinx
     default-tox-environment: py3
     sandbox: true
     auth-token: 'ph4br1cat0r'

jobs/templates/swh-pipeline.groovy.j2

@@ -98,6 +98,23 @@ pipeline {
         {%- endif %}
       }
     }
+
+    stage('Sphinx documentation') {
+      {% filter indent(width=6) %}
+        {%- include 'includes/agent-docker-sphinx.groovy.j2' -%}
+      {% endfilter %}
+
+      steps {
+        sh '''
+        if tox -a | grep -qx sphinx
+        then
+          tox -e sphinx
+        else
+          echo WARNING: no sphinx environment in tox.ini
+        fi
+        '''
+      }
+    } // sphinx doc
   } // stages
 
   post {

jobs/templates/swh-pipeline.yaml

@@ -4,6 +4,7 @@
     project-type: pipeline
     docker_image: tox
     cypress_docker_image: cypress
+    sphinx_docker_image: sphinx
     default-tox-environment: py3
     triggers:
       - timed: '@daily'

[Phabricator Migration user]

Some references in the commit message have been migrated:

• T3258 is now swh/meta#3258