From 778dafe1b60675abedacec30bbbec1e174fec5b0 Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Sun, 24 Jan 2021 11:59:16 +0000
Subject: [PATCH] Proxy requests to the prometheus and alertmanager web UIs

---
 cookbooks/prometheus/recipes/server.rb           | 16 ++++++++++++++++
 .../prometheus/templates/default/apache.erb      |  3 +++
 .../templates/default/default.alertmanager.erb   |  3 +++
 .../templates/default/default.prometheus.erb     |  3 +++
 .../templates/default/prometheus.yml.erb         |  5 ++++-
 5 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100644 cookbooks/prometheus/templates/default/default.alertmanager.erb
 create mode 100644 cookbooks/prometheus/templates/default/default.prometheus.erb

diff --git a/cookbooks/prometheus/recipes/server.rb b/cookbooks/prometheus/recipes/server.rb
index 9acc28671..d069cd8e7 100644
--- a/cookbooks/prometheus/recipes/server.rb
+++ b/cookbooks/prometheus/recipes/server.rb
@@ -169,6 +169,13 @@ search(:node, "recipes:prometheus\\:\\:default").sort_by(&:name).each do |client
   end
 end
 
+template "/etc/default/prometheus" do
+  source "default.prometheus.erb"
+  owner "root"
+  group "root"
+  mode "644"
+end
+
 template "/etc/prometheus/prometheus.yml" do
   source "prometheus.yml.erb"
   owner "root"
@@ -179,9 +186,17 @@ end
 
 service "prometheus" do
   action [:enable, :start]
+  subscribes :restart, "template[/etc/default/prometheus]"
   subscribes :reload, "template[/etc/prometheus/prometheus.yml]"
 end
 
+template "/etc/default/prometheus-alertmanager" do
+  source "default.alertmanager.erb"
+  owner "root"
+  group "root"
+  mode "644"
+end
+
 template "/etc/prometheus/alertmanager.yml" do
   source "alertmanager.yml.erb"
   owner "root"
@@ -191,6 +206,7 @@ end
 
 service "prometheus-alertmanager" do
   action [:enable, :start]
+  subscribes :restart, "template[/etc/default/prometheus-alertmanager]"
   subscribes :reload, "template[/etc/prometheus/alertmanager.yml]"
 end
 
diff --git a/cookbooks/prometheus/templates/default/apache.erb b/cookbooks/prometheus/templates/default/apache.erb
index b4c7c55ac..00760ed43 100644
--- a/cookbooks/prometheus/templates/default/apache.erb
+++ b/cookbooks/prometheus/templates/default/apache.erb
@@ -23,6 +23,9 @@
 	SSLCertificateFile /etc/ssl/certs/prometheus.openstreetmap.org.pem
 	SSLCertificateKeyFile /etc/ssl/private/prometheus.openstreetmap.org.key
 
+	ProxyPass /prometheus http://localhost:9090/prometheus
+	Redirect 403 /alertmanager/api
+	ProxyPass /alertmanager http://localhost:9093/alertmanager
 	ProxyPass / http://localhost:3000/
 	ProxyPreserveHost on
 </VirtualHost>
diff --git a/cookbooks/prometheus/templates/default/default.alertmanager.erb b/cookbooks/prometheus/templates/default/default.alertmanager.erb
new file mode 100644
index 000000000..42d6e3a3d
--- /dev/null
+++ b/cookbooks/prometheus/templates/default/default.alertmanager.erb
@@ -0,0 +1,3 @@
+# DO NOT EDIT - This file is being maintained by Chef
+
+ARGS="--web.external-url=https://prometheus.openstreetmap.org/alertmanager"
diff --git a/cookbooks/prometheus/templates/default/default.prometheus.erb b/cookbooks/prometheus/templates/default/default.prometheus.erb
new file mode 100644
index 000000000..451faa78c
--- /dev/null
+++ b/cookbooks/prometheus/templates/default/default.prometheus.erb
@@ -0,0 +1,3 @@
+# DO NOT EDIT - This file is being maintained by Chef
+
+ARGS="--web.external-url=https://prometheus.openstreetmap.org/prometheus"
diff --git a/cookbooks/prometheus/templates/default/prometheus.yml.erb b/cookbooks/prometheus/templates/default/prometheus.yml.erb
index b44654463..b7a3cf81e 100644
--- a/cookbooks/prometheus/templates/default/prometheus.yml.erb
+++ b/cookbooks/prometheus/templates/default/prometheus.yml.erb
@@ -6,7 +6,8 @@ global:
 
 alerting:
   alertmanagers:
-    - static_configs:
+    - path_prefix: /alertmanager
+      static_configs:
         - targets:
             - localhost:9093
 
@@ -17,10 +18,12 @@ scrape_configs:
   - job_name: prometheus
     scrape_interval: 5s
     scrape_timeout: 5s
+    metrics_path: /prometheus/metrics
     static_configs:
       - targets:
           - localhost:9090
   - job_name: alertmanager
+    metrics_path: /alertmanager/metrics
     static_configs:
       - targets:
           - localhost:9093
-- 
2.45.1