Split prometheus image defaults to prefix and version

To allow easier testing and deployment from different repos, image defaults were split to prefix and version that can be set externally.

bz: https://bugzilla.redhat.com/show_bug.cgi?id=1493431

roles/openshift_prometheus/README.md

@@ -19,7 +19,9 @@ For default values, see [`defaults/main.yaml`](defaults/main.yaml).
 
 - `openshift_prometheus_node_selector`: Selector for the nodes prometheus will be deployed on.
 
-- `openshift_prometheus_image_<COMPONENT>`: specify image for the component 
+- `openshift_prometheus_<COMPONENT>_image_prefix`: specify image prefix for the component 
+
+- `openshift_prometheus_<COMPONENT>_image_version`: specify image version for the component 
 
 ## PVC related variables
 Each prometheus component (prometheus, alertmanager, alertbuffer) can set pv claim by setting corresponding role variable:

roles/openshift_prometheus/defaults/main.yaml

@@ -6,11 +6,15 @@ openshift_prometheus_namespace: prometheus
 
 openshift_prometheus_node_selector: {"region":"infra"}
 
-# images
-openshift_prometheus_image_proxy: "openshift/oauth-proxy:v1.0.0"
-openshift_prometheus_image_prometheus: "openshift/prometheus:v2.0.0-dev.3"
-openshift_prometheus_image_alertmanager: "openshift/prometheus-alertmanager:v0.9.1"
-openshift_prometheus_image_alertbuffer: "openshift/prometheus-alert-buffer:v0.0.2"
+# image defaults
+openshift_prometheus_image_prefix: "openshift/"
+openshift_prometheus_image_version: "v2.0.0-dev.3"
+openshift_prometheus_proxy_image_prefix: "openshift/"
+openshift_prometheus_proxy_image_version: "v1.0.0"
+openshift_prometheus_alertmanager_image_prefix: "openshift/"
+openshift_prometheus_alertmanager_image_version: "v0.9.1"
+openshift_prometheus_alertbuffer_image_prefix: "openshift/"
+openshift_prometheus_alertbuffer_image_version: "v0.0.2"
 
 # additional prometheus rules file
 openshift_prometheus_additional_rules_file: null

roles/openshift_prometheus/templates/prometheus.j2

@@ -29,7 +29,7 @@ spec:
       containers:
       # Deploy Prometheus behind an oauth proxy
       - name: prom-proxy
-        image: "{{ openshift_prometheus_image_proxy }}"
+        image: "{{openshift_prometheus_proxy_image_prefix}}oauth-proxy:{{openshift_prometheus_proxy_image_version}}"
         imagePullPolicy: IfNotPresent
         resources:
           requests:
@@ -79,7 +79,7 @@ spec:
         - --storage.tsdb.min-block-duration=2m
         - --config.file=/etc/prometheus/prometheus.yml
         - --web.listen-address=localhost:9090
-        image: "{{ openshift_prometheus_image_prometheus }}"
+        image: "{{openshift_prometheus_image_prefix}}prometheus:{{openshift_prometheus_image_version}}"
         imagePullPolicy: IfNotPresent
         resources:
           requests:
@@ -105,7 +105,7 @@ spec:
 
       # Deploy alertmanager behind prometheus-alert-buffer behind an oauth proxy
       - name: alerts-proxy
-        image: "{{ openshift_prometheus_image_proxy }}"
+        image: "{{openshift_prometheus_proxy_image_prefix}}oauth-proxy:{{openshift_prometheus_proxy_image_version}}"
         imagePullPolicy: IfNotPresent
         resources:
           requests:
@@ -149,7 +149,7 @@ spec:
       - name: alert-buffer
         args:
         - --storage-path=/alert-buffer/messages.db
-        image: "{{ openshift_prometheus_image_alertbuffer }}"
+        image: "{{openshift_prometheus_alertbuffer_image_prefix}}prometheus-alert-buffer:{{openshift_prometheus_alertbuffer_image_version}}"
         imagePullPolicy: IfNotPresent
         resources:
           requests:
@@ -176,7 +176,7 @@ spec:
       - name: alertmanager
         args:
         - -config.file=/etc/alertmanager/alertmanager.yml
-        image: "{{ openshift_prometheus_image_alertmanager }}"
+        image: "{{openshift_prometheus_alertmanager_image_prefix}}prometheus-alertmanager:{{openshift_prometheus_alertmanager_image_version}}"
         imagePullPolicy: IfNotPresent
         resources:
           requests: