reachlin · April 19, 2017 07:06 · Apr 19, 2017
diff --git a/prometheus.yml b/prometheus.yml
@@ -0,0 +1,61 @@
+  // For all the confusing Prometheus configuration and
+  // regular expressions,
+  // explained in examples.
+
+
+  // Remember, there are default values for each item if it's missing.
+  // regex is (.*),
+  // replacement is $1,
+  // separator is ;
+  // ,and action is replace 
+
+  relabel_configs:
+  - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
+    action: keep
+    regex: true
+    // keep targets with label __meta_kubernetes_service_annotation_prometheus_io_scrape equals 'true',
+    // which means the user added prometheus.io/scrape: true in the service's annotation.
+
+  - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scheme]
+    action: replace
+    target_label: __scheme__
+    regex: (https?)
+    // if __meta_kubernetes_service_annotation_prometheus_io_scheme is http or https, replace __scheme__ with its value that is the default replacement: $1.
+    // this means the user added prometheus.io/scheme in the service's annotation.
+
+  - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
+    action: replace
+    target_label: __metrics_path__
+    regex: (.+)
+    // this is also for service annotation of prometheus, if the user overrides the scrape path,
+    // its value will be put in __metrics_path__
+
+  - source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
+    action: replace
+    target_label: __address__
+    regex: (.+)(?::\d+);(\d+)
+    replacement: $1:$2
+    // if the user added prometheus.io/port in the service annotation,
+    // use this port to replace the port in __address__
+
+    // all above rules are for handling prometheus annotation: https://github.com/prometheus/prometheus/blob/master/documentation/examples/prometheus-kubernetes.yml
+
+  - action: labelmap
+    regex: __meta_kubernetes_service_label_(.+)
+    // all __meta_kubernetes_service_label_(.+) will be changed to the (.+)
+    // e.g. __meta_kubernetes_service_label_app='armada-api' to app='armada-api'
+
+  - source_labels: [__meta_kubernetes_namespace]
+    action: replace
+    target_label: kubernetes_namespace
+    // if __meta_kubernetes_namespace matches .*, put its value in label kubernetes_namespace
+
+  - source_labels: [__meta_kubernetes_service_name]
+    action: replace
+    target_label: service_name
+    // if __meta_kubernetes_service_name matches .*, put its value in label service_name
+
+  - source_labels: [__meta_kubernetes_pod_node_name]
+    action: replace
+    target_label: hostname
+    // if __meta_kubernetes_pod_node_name matches .*, put its value in label hostname