nginx load-balances a dummy http server

hammerhead/README.md

@@ -9,7 +9,9 @@
 
 1. Base components: things that need to be installed before services
 
-	* Reverse-proxy/load-balancer: `nginx` is a good match for a one-node deployment. Installing it with Nomad/Consul will make me practice Consul Template etc. 
+	* [x] Dummy HTTP server to have something to work with.
+	* [x] Reverse-proxy/load-balancer: `nginx` is a good match for a one-node deployment. Installing it with Nomad/Consul will make me practice Consul Template etc. 
+	* Generate services configuration outside the `nginx` service definition.
 	* TLS: Let's Encrypt will probably be part of the same job definition as `nginx`.
 
 2. Gitea migration

hammerhead/app/dummy-http-server/deploy/dummy-http-server.hcl

@@ -0,0 +1,38 @@
+job "dummy-http-server" {
+  datacenters = ["dc1"]
+  group "server-group" {
+    count = 5
+    
+    # update {
+    #   canary       = 1
+    #   max_parallel = 5
+    # }
+
+    network {
+      port "http" {}
+    }
+
+    service {
+      name = "dummy-http-server"
+      port = "http"
+      check {
+        type     = "http"
+        path     = "/health"
+        interval = "2s"
+        timeout  = "2s"
+      }
+    }
+
+    task "server" {
+      driver = "docker"
+      
+      config {
+        image = "hashicorp/http-echo:latest"
+        args  = [
+          "-listen", ":${NOMAD_PORT_http}",
+          "-text", "Hello and welcome to ${NOMAD_IP_http}:${NOMAD_PORT_http}",
+        ]
+      }
+    }
+  }
+}

hammerhead/app/nginx/deploy/nginx.hcl

@@ -0,0 +1,55 @@
+job "nginx" {
+  datacenters = ["dc1"]
+
+  group "nginx" {
+    count = 1
+
+    network {
+      port "http" {
+        static = 8080
+      }
+    }
+
+    service {
+      name = "nginx"
+      port = "http"
+    }
+
+    task "nginx" {
+      driver = "docker"
+
+      config {
+        image = "nginx"
+
+        ports = ["http"]
+
+        volumes = [
+          "local:/etc/nginx/conf.d",
+        ]
+      }
+
+      template {
+        data = <<EOF
+upstream dummy-http-server-backend {
+{{ range service "dummy-http-server" }}
+  server {{ .Address }}:{{ .Port }};
+{{ else }}server 127.0.0.1:65535; # force a 502
+{{ end }}
+}
+
+server {
+   listen 8080;
+
+   location / {
+      proxy_pass http://dummy-http-server-backend;
+   }
+}
+EOF
+
+        destination   = "local/dummy-http-server-load-balancer.conf"
+        change_mode   = "signal"
+        change_signal = "SIGHUP"
+      }
+    }
+  }
+}