roles/dch-proxy: Add backend for Jenkins

This commit configures HAProxy to proxy *jenkins.pyrocufflink.net* and
*jenkins.pyrocufflink.blue* to the Jenkins master.

roles/dch-proxy/tasks/main.yml

@@ -18,3 +18,10 @@
     dest=/etc/haproxy/70-backend-gitea.cfg
     mode=0644
   notify: reload haproxy
+
+- name: ensure jenkins haproxy backend is configured
+  template:
+    src=backend-jenkins.haproxy.cfg.j2
+    dest=/etc/haproxy/70-backend-jenkins.cfg
+    mode=0644
+  notify: reload haproxy

roles/dch-proxy/templates/backend-jenkins.haproxy.cfg.j2

@@ -0,0 +1,7 @@
+backend jenkins
+	server jenkins jenkins.pyrocufflink.blue:80 check
+
+
+backend jenkins-tls
+	mode tcp
+	server jenkins jenkins.pyrocufflink.blue:443 check

roles/dch-proxy/templates/frontend-main.haproxy.cfg.j2

@@ -3,6 +3,8 @@ frontend main
 
     use_backend gitea if { hdr(host) -i git.pyrocufflink.blue }
     use_backend gitea if { hdr(host) -i git.pyrocufflink.net }
+    use_backend jenkins if { hdr(host) -i jenkins.pyrocufflink.blue }
+    use_backend jenkins if { hdr(host) -i jenkins.pyrocufflink.net }
     default_backend myala
 
 
@@ -16,4 +18,6 @@ frontend main-tls
 
     use_backend gitea-tls if { req_ssl_sni -i git.pyrocufflink.blue }
     use_backend gitea-tls if { req_ssl_sni -i git.pyrocufflink.net }
+    use_backend jenkins-tls if { req_ssl_sni -i jenkins.pyrocufflink.blue }
+    use_backend jenkins-tls if { req_ssl_sni -i jenkins.pyrocufflink.net }
     default_backend myala-tls