feat(infra/k8s): Rewrite cgit URLs by routing them through nginx r/229

Configures nginx to rewrite all requests to cgit, except for those
retrieving static files, to `/depot/`.

In combination with the previous commits that apply patches to cgit
itself, this effectively means that the depot is rendered on the site
root.

This is pretty cool: It lets people do stuff like `git clone
https://git.tazj.in` and get the depot!

3 files changed, 27 insertions, 10 deletions

diff --git a/infra/kubernetes/cgit/config.yaml b/infra/kubernetes/cgit/config.yaml
index 577a56650a..e48544d507 100644
--- a/infra/kubernetes/cgit/config.yaml
+++ b/infra/kubernetes/cgit/config.yaml
@@ -65,10 +65,9 @@ kind: Service
 metadata:
   name: cgit
 spec:
-  type: NodePort
   selector:
     app: cgit
   ports:
     - protocol: TCP
-      port: 2448 # cgit
+      port: 80
       targetPort: 8080
diff --git a/infra/kubernetes/https-lb/ingress.yaml b/infra/kubernetes/https-lb/ingress.yaml
index 0a3092da20..069771a421 100644
--- a/infra/kubernetes/https-lb/ingress.yaml
+++ b/infra/kubernetes/https-lb/ingress.yaml
@@ -8,20 +8,23 @@ metadata:
   annotations:
     networking.gke.io/managed-certificates: tazj-in, git-tazj-in, www-tazj-in, oslo-pub
 spec:
-  # Default traffic is routed to the blog, in case people go to
-  # peculiar hostnames.
-  backend:
-    serviceName: tazblog
-    servicePort: 8000
   rules:
+    # Route blog to the blog ...
+    - host: tazj.in
+      http:
+        paths:
+          - path: /*
+            backend:
+              serviceName: tazblog
+              servicePort: 8000
     # Route git.tazj.in to the cgit pods
     - host: git.tazj.in
       http:
         paths:
-          - path: /
+          - path: /*
             backend:
-              serviceName: cgit
-              servicePort: 2448
+              serviceName: nginx
+              servicePort: 6756
     # Route oslo.pub to the nginx instance which serves redirects
     - host: oslo.pub
       http:
diff --git a/infra/kubernetes/nginx/nginx.conf b/infra/kubernetes/nginx/nginx.conf
index ead5c40617..918aa60678 100644
--- a/infra/kubernetes/nginx/nginx.conf
+++ b/infra/kubernetes/nginx/nginx.conf
@@ -41,4 +41,19 @@ http {
             return 302 https://www.google.com/maps/d/viewer?mid=1pJIYY9cuEdt9DuMTbb4etBVq7hs;
         }
     }
+
+    server {
+        listen       80;
+        server_name  git.tazj.in;
+
+        # Static assets must always hit the root.
+        location ~ ^/(favicon\.ico|cgit\.(css|png))$ {
+           proxy_pass http://cgit;
+        }
+
+        # Everything else hits the depot directly.
+        location / {
+            proxy_pass http://cgit/cgit.cgi/depot/;
+        }
+    }
 }