Switch to envvars from init container

Author: malcolmholmes

prometheus-ksonnet/lib/prometheus-ha-mixin.libsonnet

@@ -1,3 +1,6 @@
+local container = $.core.v1.container;
+local statefulset = $.apps.v1.statefulSet;
+
 {
   prometheus_config_0: $.prometheus_config,
   prometheus_config_1: $.prometheus_config,
@@ -30,13 +33,14 @@
 
   prometheus_config_mount:: {},
 
-  prometheus_init_container::
-    container.new('prometheus-init', 'busybox') +
-    container.withCommand(["ln", "-s", "/etc/$HOSTNAME", "/etc/prometheus"]),
+  prometheus_config_file:: '/etc/$(POD_NAME)/prometheus.yml',
+
+  prometheus_container+:: container.withEnv([
+      container.envType.fromFieldPath('POD_NAME', 'metadata.name'),
+    ]),
 
   prometheus_statefulset:
     $.util.configVolumeMount('%s-config-0' % self.name, '/etc/prometheus-0') +
     $.util.configVolumeMount('%s-config-1' % self.name, '/etc/prometheus-1') +
-    statefulset.mixin.spec.template.spec.withInitContainers(self.prometheus_init_container) +
     statefulset.mixin.spec.withReplicas(2),
 }

prometheus-ksonnet/lib/prometheus.libsonnet

@@ -30,13 +30,15 @@
 
     local container = $.core.v1.container,
 
+    prometheus_config_file:: '/etc/prometheus/prometheus.yml',
+
     prometheus_container::
       local _config = self._config;
 
       container.new('prometheus', $._images.prometheus) +
       container.withPorts($.core.v1.containerPort.new('http-metrics', _config.prometheus_port)) +
       container.withArgs([
-        '--config.file=/etc/prometheus/prometheus.yml',
+        '--config.file=' + self.prometheus_config_file,
         '--web.listen-address=:%s' % _config.prometheus_port,
         '--web.external-url=%(prometheus_external_hostname)s%(prometheus_path)s' % _config,
         '--web.enable-admin-api',