Documentation for custom KEDA scaler for Splunk Observability Cloud

content/docs/2.16/scalers/splunk_observability.md

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+title = "Splunk Observability"
+availability = "v2.15+"
+maintainer = "Community"
+category = "Data & Storage"
+description = "Scale applications based on Splunk Observability Cloud metrics."
+go_file = "splunk_observability_scaler"
++++
+
+### Trigger Specification
+
+This specification describes the `splunk-observability` trigger that scales based on the result of a metric series queried from the Splunk Observability Cloud platform with a [SignalFlow query](https://dev.splunk.com/observability/docs/signalflow/).
+
+The trigger always requires the following information:
+
+```yaml
+triggers:
+  - type: splunk-observability
+    metricType: Value
+    metadata:
+      query: "data('demo.trans.latency').max().publish()"
+      duration: "10"
+      targetValue: "400.1"
+      activationTargetValue: "1.1"
+      queryAggregator: "avg"
+```
+
+**Parameter list:**
+
+- `query` - SignalFlow query for querying the desired metrics.
+- `duration` - Duration of the stream being created to query a Metric Time Series (MTS) from Splunk Observability Cloud. The specified duration is in seconds.
+- `targetValue` - Threshold to reach to start scaling.
+- `activationTargetValue` - Target value for activating the scaler. Learn more about activation [here](./../concepts/scaling-deployments.md#activating-and-scaling-thresholds).
+- `queryAggregator` - When querying metrics from Splunk Observability Cloud, initially a Metric Time Series (MTS) is returned, a list consiting of several datapoints. The 'queryAggregator' speicifies how this series of metrics should be "rolled up". Valid values for this field are "avg", which returnes the average, "min", which returns the minimun of the metrics in the series, and "max", which returns the maximun value.
+
+### Authentication Parameters
+
+You can authenticate by using an access token and a realm for Splunk Observability Cloud. You will need to use `TriggerAuthentication` CRD to configure the authentication.
+
+> **Note:**
+>
+> `TriggerAuthentication` is required to use this scaler due to the hard requirement of providing a `accessToken` and a `realm` for Splunk Observability Cloud.
+
+**Parameter list:**
+
+- `accessToken` - Splunk Observability Cloud Access Token.
+- `realm` - Splunk Observability Cloud Realm.
+
+### Example
+
+The following example shows how to scale a simple NGINX employment with the help of KEDA and the Splunk Observability Cloud scaler:
+
+#### Simple NGINX employment
+
+```yaml
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: nginx
+spec:
+  selector:
+    matchLabels:
+      app: nginx
+  replicas: 1 
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx:1.14.2
+        ports:
+        - containerPort: 80
+```
+
+#### Authentication
+
+```yaml
+---
+apiVersion: v1
+kind: Secret
+metadata:
+  name: splunk-secrets
+data:
+  accessToken: dGVzdF9hY2Nlc3NfdG9rZW4= # base64-encrypted example access token
+  realm: dGVzdF9yZWFsbQ== # base64-encrypted example realm
+---
+apiVersion: keda.sh/v1alpha1
+kind: TriggerAuthentication
+metadata:
+  name: keda-trigger-auth-splunk-secret
+spec:
+  secretTargetRef:
+  - parameter: accessToken
+    name: splunk-secrets
+    key: accessToken
+  - parameter: realm
+    name: splunk-secrets
+    key: realm
+```
+
+#### Keda Scaler
+```yaml
+---
+apiVersion: keda.sh/v1alpha1
+kind: ScaledObject
+metadata:
+  name: keda
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: nginx
+  pollingInterval: 30
+  cooldownPeriod: 30
+  minReplicaCount: 1
+  maxReplicaCount: 10
+  triggers:
+  - type: splunk-observability
+    metricType: Value
+    metadata:
+      query: "data('demo.trans.count', filter=filter('demo_host', 'server6'), rollup='rate').sum(by=['demo_host']).publish()" 
+      duration: "10"
+      queryValue: "400.1"
+      activationQueryValue: "1.1"
+      queryAggregator: "max" # 'min', 'max', or 'avg' 
+    authenticationRef:
+      name: keda-trigger-auth-splunk-secret
+```