+++ title = "Kubernetes Resource" availability = "v2.19+" maintainer = "Community" category = "Kubernetes" description = "Scale applications based on values in Kubernetes ConfigMaps or Secrets" go_file = "kubernetes_resource_scaler" +++ ### Trigger Specification This specification describes the `kubernetes-resource` trigger that scales based on a value found in a Kubernetes ConfigMap or Secret. This scaler allows users to scale workloads by extracting values from Kubernetes resources, supporting number, JSON, and YAML formats. Here is an example of trigger configuration using kubernetes-resource scaler: ```yaml triggers: - type: kubernetes-resource metadata: resourceKind: "Secret" resourceName: "my-secret" key: "data" format: "json" valueLocation: "count" valueType: "float64" targetValue: "10" activationTargetValue: "5" ``` **Parameter list:** - `resourceKind` - Type of Kubernetes resource to read from. Supported values: `ConfigMap`, `Secret` (Required) - `resourceName` - Name of the resource to read. (Required) - `key` - Key in the ConfigMap's `data` field or Secret's `data` field to read from. The value at this key is retrieved as a string. (Required) - `format` - Format of the string value retrieved from `key`. Supported values: `number`, `json`, `yaml`. (Default: `number`, Optional) - `number` - The string value is parsed directly as a number - `json` - The string value is a JSON document, and `valueLocation` extracts a field from it - `yaml` - The string value is a YAML document, and `valueLocation` extracts a field from it - `valueLocation` - Path to extract the metric value from the JSON or YAML content retrieved from `key`. Required for `json` and `yaml` formats. Not used for `number` format. For `json`, use [GJSON path notation](https://github.com/tidwall/gjson#path-syntax). For `yaml`, use dot-separated path (e.g., `foo.bar.count`). (Optional) - `valueType` - Type of value to extract. Supported values: `float64`, `int64`, `quantity`. (Default: `float64`, Optional) - `float64` - Floating point number. For JSON format, accepts both numbers and quantity strings. - `int64` - Integer number. For JSON format, only accepts integer numbers (decimal values are truncated). For `number` format, the string must be parseable as an integer. - `quantity` - Kubernetes quantity (e.g., "100m", "1Gi"). For JSON/YAML formats, parses string values as quantities. For JSON format, also accepts raw numbers. - `targetValue` - Target value to scale on. When the extracted value is equal or higher, KEDA will scale out. (Required) - `activationTargetValue` - Value for activating the scaler. Learn more about activation [here](./../concepts/scaling-deployments.md#activating-and-scaling-thresholds). (Default: `0`, Optional) ### Authentication Parameters No authentication parameters are required. The scaler uses the permissions of the KEDA operator to access resources in the same namespace. ### Example Here is a full example of scaled object definition using Kubernetes Resource trigger: ```yaml apiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: k8s-resource-scaledobject namespace: keda spec: maxReplicaCount: 10 scaleTargetRef: name: dummy triggers: - type: kubernetes-resource metadata: resourceKind: "ConfigMap" resourceName: "my-configmap" key: "metrics" format: "yaml" valueLocation: "count" valueType: "int64" targetValue: "10" ``` Assuming the ConfigMap contains: ```yaml apiVersion: v1 kind: ConfigMap metadata: name: my-configmap namespace: keda data: metrics: | count: 12 other: value ``` The scaler will extract the value at `count` from the YAML data in the `metrics` key and use it for scaling decisions. > 💡 **NOTE:** > - The `valueType` parameter controls how values are parsed. For `int64`, decimal values in JSON are truncated to integers. > - For `json` format, use GJSON path syntax. For `yaml` format, use dot-separated path. For `number` format, the value at the key is used directly. > - For YAML format, the `valueType` determines how the extracted value is converted, regardless of whether the value is a string or a native YAML number. For example, if `valueType` is set to `int64`, the value will be converted to an integer; if set to `quantity`, it will be parsed as a Kubernetes quantity. By default, numeric YAML values are converted to float64 unless a different `valueType` is specified. ### Additional Examples #### Example 1: Number Format (Direct Value) ```yaml apiVersion: v1 kind: ConfigMap metadata: name: task-count namespace: keda data: count: "42" --- apiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: task-scaler namespace: keda spec: scaleTargetRef: name: worker-deployment triggers: - type: kubernetes-resource metadata: resourceKind: "ConfigMap" resourceName: "task-count" key: "count" format: "number" valueType: "float64" targetValue: "50" activationTargetValue: "10" ``` In this example, the value `42` from the `count` key is used directly. #### Example 2: JSON Format ```yaml apiVersion: v1 kind: Secret metadata: name: metrics-data namespace: keda stringData: metrics: | { "queue": { "pending": 25, "processing": 5 } } --- apiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: queue-scaler namespace: keda spec: scaleTargetRef: name: processor-deployment triggers: - type: kubernetes-resource metadata: resourceKind: "Secret" resourceName: "metrics-data" key: "metrics" format: "json" valueLocation: "queue.pending" valueType: "int64" targetValue: "20" ``` In this example, the GJSON path `queue.pending` extracts the value `25` from the JSON data. #### Example 3: YAML Format with Nested Path ```yaml apiVersion: v1 kind: ConfigMap metadata: name: app-metrics namespace: keda data: stats: | application: workers: active: 15 idle: 3 --- apiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: worker-scaler namespace: keda spec: scaleTargetRef: name: worker-deployment triggers: - type: kubernetes-resource metadata: resourceKind: "ConfigMap" resourceName: "app-metrics" key: "stats" format: "yaml" valueLocation: "application.workers.active" valueType: "int64" targetValue: "10" ``` In this example, the dot-separated path `application.workers.active` extracts the value `15` from the YAML data. #### Example 4: Quantity Type ```yaml apiVersion: v1 kind: ConfigMap metadata: name: resource-limits namespace: keda data: memory: | { "available": "2Gi", "used": "512Mi" } --- apiVersion: keda.sh/v1alpha1 kind: ScaledObject metadata: name: memory-scaler namespace: keda spec: scaleTargetRef: name: worker-deployment triggers: - type: kubernetes-resource metadata: resourceKind: "ConfigMap" resourceName: "resource-limits" key: "memory" format: "json" valueLocation: "used" valueType: "quantity" targetValue: "1024000000" # 1Gi in bytes ``` In this example, the quantity string `"512Mi"` is parsed and converted to its float64 representation for scaling decisions. > ⚠️ **Important:** When using `valueType: "int64"` with JSON format, decimal values will be truncated. For example, if the JSON contains `{"count": 25.7}`, it will be treated as `25`. ### Supported Formats and Value Extraction The scaler works in two steps: 1. **Retrieve the raw string**: Read the value from `ConfigMap.data[key]` or `Secret.data[key]` 2. **Extract the metric**: Parse the raw string based on the `format`: - **number**: The raw string is parsed directly as a number. No `valueLocation` is needed. - Example: If `key="count"` and `ConfigMap.data.count = "42"`, the metric value is `42` - **json**: The raw string is parsed as JSON, then `valueLocation` (using GJSON syntax) extracts the metric value. - Example: If `key="metrics"` and `ConfigMap.data.metrics = '{"tasks": 10}'`, with `valueLocation="tasks"`, the metric value is `10` - **yaml**: The raw string is parsed as YAML, then `valueLocation` (using dot-separated path) extracts the metric value. - Example: If `key="stats"` and `ConfigMap.data.stats = 'count: 15'`, with `valueLocation="count"`, the metric value is `15` ### Limitations - Only resources in the same namespace as the ScaledObject are supported. - No cross-namespace access. - Only ConfigMaps and Secrets are supported. - The scaler uses the KEDA operator's service account permissions to access resources. ### See Also - [KEDA Concepts: Activating and Scaling Thresholds](./../concepts/scaling-deployments.md#activating-and-scaling-thresholds) - [GJSON Path Syntax](https://github.com/tidwall/gjson#path-syntax)