salt: add CSC mechanism to Loki

Refs: #2682

buildchain/buildchain/salt_tree.py

@@ -271,8 +271,11 @@ def _get_parts(self) -> Iterator[str]:
 
     Path('salt/metalk8s/addons/logging/deployed/init.sls'),
     Path('salt/metalk8s/addons/logging/deployed/namespace.sls'),
+    Path('salt/metalk8s/addons/logging/loki/config/loki.yaml'),
     Path('salt/metalk8s/addons/logging/loki/deployed/chart.sls'),
     Path('salt/metalk8s/addons/logging/loki/deployed/init.sls'),
+    Path('salt/metalk8s/addons/logging/loki/deployed/loki-configuration-secret.sls'),
+    Path('salt/metalk8s/addons/logging/loki/deployed/service-configuration.sls'),
 
     Path('salt/metalk8s/addons/prometheus-adapter/deployed/chart.sls'),
     Path('salt/metalk8s/addons/prometheus-adapter/deployed/init.sls'),

salt/metalk8s/addons/logging/loki/config/loki.yaml

@@ -0,0 +1,44 @@
+---
+# Configuration of the Loki service
+apiVersion: addons.metalk8s.scality.com
+kind: LokiConfig
+spec:
+  deployment:
+    replicas: 1
+  config:
+    auth_enabled: false
+    chunk_store_config:
+      max_look_back_period: 0s
+    ingester:
+      chunk_block_size: 262144
+      chunk_idle_period: 3m
+      chunk_retain_period: 1m
+      lifecycler:
+        ring:
+          kvstore:
+            store: inmemory
+          replication_factor: 1
+      max_transfer_retries: 0
+    limits_config:
+      enforce_metric_name: false
+      reject_old_samples: true
+      reject_old_samples_max_age: 168h
+    schema_config:
+      configs:
+      - from: 2018-04-15
+        index:
+          period: 168h
+          prefix: index_
+        object_store: filesystem
+        schema: v9
+        store: boltdb
+    server:
+      http_listen_port: 3100
+    storage_config:
+      boltdb:
+        directory: /data/loki/index
+      filesystem:
+        directory: /data/loki/chunks
+    table_manager:
+      retention_deletes_enabled: false
+      retention_period: 0s

salt/metalk8s/addons/logging/loki/deployed/init.sls

@@ -1,2 +1,4 @@
 include:
+  - .service-configuration
+  - .loki-configuration-secret
   - .chart

salt/metalk8s/addons/logging/loki/deployed/loki-configuration-secret.sls

@@ -0,0 +1,26 @@
+{% import_yaml 'metalk8s/addons/logging/loki/config/loki.yaml' as loki_defaults with context %}
+
+{%- set loki = salt.metalk8s_service_configuration.get_service_conf(
+        'metalk8s-logging', 'metalk8s-loki-config', loki_defaults
+    )
+%}
+
+Create Loki Configuration Secret:
+  metalk8s_kubernetes.object_present:
+    - manifest:
+        apiVersion: v1
+        kind: Secret
+        metadata:
+          labels:
+            app: loki
+            app.kubernetes.io/managed-by: salt
+            app.kubernetes.io/name: loki
+            app.kubernetes.io/part-of: metalk8s
+            chart: loki-0.30.2
+            heritage: metalk8s
+            release: loki
+          name: loki
+          namespace: metalk8s-logging
+        stringData:
+          loki.yaml: |-
+            {{ loki.spec.config | tojson }}

salt/metalk8s/addons/logging/loki/deployed/service-configuration.sls

@@ -0,0 +1,30 @@
+{%- set loki_config = salt.metalk8s_kubernetes.get_object(
+        kind='ConfigMap',
+        apiVersion='v1',
+        namespace='metalk8s-logging',
+        name='metalk8s-loki-config',
+    )
+%}
+
+{%- if loki_config is none %}
+
+Create metalk8s-loki-config ConfigMap:
+  metalk8s_kubernetes.object_present:
+    - manifest:
+        apiVersion: v1
+        kind: ConfigMap
+        metadata:
+          name: metalk8s-loki-config
+          namespace: metalk8s-logging
+        data:
+          config.yaml: |-
+            apiVersion: addons.metalk8s.scality.com
+            kind: LokiConfig
+            spec: {}
+
+{%- else %}
+
+metalk8s-loki-config ConfigMap already exist:
+  test.succeed_without_changes: []
+
+{%- endif %}