add timeout parameter for HTTP client in Azure Log Analytics and Prometheus scalers (#1548)

Signed-off-by: Zbynek Roubalik <zroubalik@gmail.com>

Author: zroubalik

content/docs/2.17/operate/cluster.md

@@ -70,7 +70,7 @@ Some scalers issue HTTP requests to external servers (i.e. cloud services). Each
 
 You can override this default by setting the `KEDA_HTTP_DEFAULT_TIMEOUT` environment variable on the KEDA operator deployment to your desired timeout in milliseconds.
 
-> ⚠️ All applicable scalers will use this timeout and setting this on a per-scaler is currently not supported.
+> ⚠️ All applicable scalers will use this timeout, although some scalers allow you to override this global setting via the `timeout` parameter in the trigger metadata.
 
 ## HTTP Connection: Disable Keep Alive
 

content/docs/2.17/scalers/azure-log-analytics.md

@@ -57,6 +57,8 @@ triggers:
       activeDirectoryEndpoint: https://login.airgap.example/
       # Optional (Default: false)
       unsafeSsl: "false"
+      # Optional. Custom timeout for the HTTP client used in this scaler
+      timeout: 1000
 ```
 
 **Parameter list:**
@@ -72,6 +74,7 @@ triggers:
 - `logAnalyticsResourceURL` - Log Analytics REST API URL of the cloud environment. (Required when `cloud` is set to `Private`, e.g. `https://api.loganalytics.azure.cn/` for `AzureChinaCloud`).
 - `activeDirectoryEndpoint` - Active Directory endpoint of the cloud environment. (Required when `cloud` is set to `Private`, e.g. `https://login.chinacloudapi.cn/` for `AzureChinaCloud`).
 - `unsafeSsl` - Determines whether or not KEDA will verify the server certificate's chain and host name. (Default: `false`, Optional, This value can be a bool)
+- `timeout` - Timeout in milliseconds **for this specific trigger**. This value will override the value defined in `KEDA_HTTP_DEFAULT_TIMEOUT`. (Optional)
 
 
 The authentication parameters could be provided using environmental variables, instead of setting them directly in metadata. Here is a list of parameters you can use to retrieve values from environment variables:

content/docs/2.17/scalers/prometheus.md

@@ -26,7 +26,7 @@ triggers:
     ignoreNullValues: false # Default is `true`, which means ignoring the empty value list from Prometheus. Set to `false` the scaler will return error when Prometheus target is lost
     queryParameters: key-1=value-1,key-2=value-2
     unsafeSsl: "false" #  Default is `false`, Used for skipping certificate check when having self-signed certs for Prometheus endpoint    
-
+    timeout: 1000 # Optional. Custom timeout for the HTTP client used in this scaler
 ```
 
 **Parameter list:**
@@ -40,6 +40,7 @@ triggers:
 - `ignoreNullValues` - Value to reporting error when Prometheus target is lost (Values: `true`,`false`, Default: `true`, Optional)
 - `queryParameters` - A comma-separated list of query Parameters to include while querying the Prometheus endpoint. (Optional)
 - `unsafeSsl` - Used for skipping certificate check e.g: using self-signed certs  (Values: `true`,`false`, Default: `false`, Optional)
+- `timeout` - Timeout in milliseconds **for this specific trigger**. This value will override the value defined in `KEDA_HTTP_DEFAULT_TIMEOUT`. (Optional)
 
 ### Authentication Parameters
 

content/docs/2.17/scalers/rabbitmq-queue.md

@@ -28,6 +28,7 @@ triggers:
     usernameFromEnv: RABBITMQ_USERNAME # Optional. You can use this instead of TriggerAuthentication
     passwordFromEnv: RABBITMQ_PASSWORD # Optional. You can use this instead of TriggerAuthentication
     unsafeSsl: true
+    timeout: 1000 # Optional. Custom timeout for the HTTP client used in this scaler
 ```
 
 **Parameter list:**
@@ -43,7 +44,7 @@ triggers:
 - `useRegex` - This parameter allows to use regex (in `queueName` parameter) to select queue instead of full name. (Values: `true`, `false`, Default: `false`, Optional, Only applies to hosts that use the `http` protocol)
 - `pageSize` - This parameter allows setting page size. (Default: `100`, Optional, Only applies when `useRegex` is `true`)
 - `operation` - Operation that will be applied to compute the number of messages in case of `useRegex` enabled. Either `sum` (default),`max`, or `avg`. (Optional)
-- `timeout` - Timeout **for this specific trigger**. This value will override the value defined in `KEDA_HTTP_DEFAULT_TIMEOUT`. (Optional, Only applies to hosts that use the `http` protocol)
+- `timeout` - Timeout in milliseconds **for this specific trigger**. This value will override the value defined in `KEDA_HTTP_DEFAULT_TIMEOUT`. (Optional, Only applies to hosts that use the `http` protocol)
 - `excludeUnacknowledged` - Set to `true` to specify that the `QueueLength` value should exclude unacknowledged messages (Ready messages only). (Values: `true`, `false`, Default: `false`, Optional, Only applies to hosts that use the `http` protocol)
 - `unsafeSsl` - Whether to allow unsafe SSL (Values: `true`, `false`, Default: `false` )