fix bug where prometheus environments didn't work

Author: sjpb

ansible/filter_plugins/utils.py

@@ -11,11 +11,12 @@
 import os.path
 import re
 
-def prometheus_node_exporter_targets(hosts, env):
+def prometheus_node_exporter_targets(hosts, hostvars, env_key):
     result = []
     per_env = defaultdict(list)
     for host in hosts:
-        per_env[env].append(host)
+        host_env = hostvars[host].get(env_key, 'ungrouped')
+        per_env[host_env].append(host)
     for env, hosts in per_env.items():
         target = {
             "targets": ["{target}:9100".format(target=target) for target in hosts],

environments/common/inventory/group_vars/all/prometheus.yml

@@ -22,10 +22,9 @@ prometheus_alert_rules_files: "{{ ansible_inventory_sources | product([prometheu
 
 prometheus_alert_rules: []
 
-# Can set a hostvar 'env' to an arbitrary string to group prometheus targets, e.g. rack.
-# env: location-1
+# Can set a hostvar 'prometheus_env' to an arbitrary string to group prometheus targets, e.g. by rack.
 prometheus_targets:
-  node: "{{ groups.get('node_exporter', []) | reject('equalto', 'localhost') | prometheus_node_exporter_targets(env | default('ungrouped')) }}"
+  node: "{{ groups.get('node_exporter', []) | prometheus_node_exporter_targets(hostvars, 'prometheus_env') }}"
 
 prometheus_scrape_configs_default:
 - job_name: "prometheus"
@@ -40,7 +39,7 @@ prometheus_scrape_configs_default:
 - job_name: "node"
   file_sd_configs:
   - files:
-    - "/etc/prometheus/file_sd/node.yml"
+    - /etc/prometheus/file_sd/node.yml
   relabel_configs:
   # strip off port
   - source_labels: ['__address__']