Support poolName or poolID validation in Azure Pipelines Scaler

CHANGELOG.md

@@ -23,24 +23,19 @@
 
 ### New
 
-
 - Add New Relic Scaler ([#2387](https://github.com/kedacore/keda/pull/2387))
-
 - Add ActiveMQ Scaler ([#2305](https://github.com/kedacore/keda/pull/2305))
 
-- TODO ([#XXX](https://github.com/kedacore/keda/pull/XXX))
-
 ### Improvements
 
+- Azure Pipelines Scaler: support `poolName` or `poolID` validation ([#2370](https://github.com/kedacore/keda/pull/2370))
 - Graphite Scaler: use the latest datapoint returned, not the earliest ([#2365](https://github.com/kedacore/keda/pull/2365))
 - Kubernetes Workload Scaler: ignore terminated pods ([#2384](https://github.com/kedacore/keda/pull/2384))
 - Azure EventHub Scaler: don't expose connection string in metricName ([#2404](https://github.com/kedacore/keda/pull/2404))
 - `keda-operator` Cluster Role: add `list` and `watch` access to service accounts ([#2406](https://github.com/kedacore/keda/pull/2406))|([#2410](https://github.com/kedacore/keda/pull/2410))
 - Kafka Scaler: concurrently query brokers for consumer and producer offsets ([#2405](https://github.com/kedacore/keda/pull/2405))
 - Delete the cache entry when a ScaledObject is deleted ([#2408](https://github.com/kedacore/keda/pull/2408))
 
-- TODO ([#XXX](https://github.com/kedacore/keda/pull/XXX))
-
 ### Breaking Changes
 
 - TODO ([#XXX](https://github.com/kedacore/keda/pull/XXX))

pkg/scalers/azure_pipelines_scaler.go

@@ -22,6 +22,16 @@ const (
 	defaultTargetPipelinesQueueLength = 1
 )
 
+type azurePipelinesPoolNameResponse struct {
+	Value []struct {
+		ID int `json:"id"`
+	} `json:"value"`
+}
+
+type azurePipelinesPoolIDResponse struct {
+	ID int `json:"id"`
+}
+
 type azurePipelinesScaler struct {
 	metadata   *azurePipelinesMetadata
 	httpClient *http.Client
@@ -31,29 +41,29 @@ type azurePipelinesMetadata struct {
 	organizationURL            string
 	organizationName           string
 	personalAccessToken        string
-	poolID                     string
+	poolID                     int
 	targetPipelinesQueueLength int
 	scalerIndex                int
 }
 
 var azurePipelinesLog = logf.Log.WithName("azure_pipelines_scaler")
 
 // NewAzurePipelinesScaler creates a new AzurePipelinesScaler
-func NewAzurePipelinesScaler(config *ScalerConfig) (Scaler, error) {
-	meta, err := parseAzurePipelinesMetadata(config)
+func NewAzurePipelinesScaler(ctx context.Context, config *ScalerConfig) (Scaler, error) {
+	httpClient := kedautil.CreateHTTPClient(config.GlobalHTTPTimeout, false)
+
+	meta, err := parseAzurePipelinesMetadata(ctx, config, httpClient)
 	if err != nil {
 		return nil, fmt.Errorf("error parsing azure Pipelines metadata: %s", err)
 	}
 
-	httpClient := kedautil.CreateHTTPClient(config.GlobalHTTPTimeout, false)
-
 	return &azurePipelinesScaler{
 		metadata:   meta,
 		httpClient: httpClient,
 	}, nil
 }
 
-func parseAzurePipelinesMetadata(config *ScalerConfig) (*azurePipelinesMetadata, error) {
+func parseAzurePipelinesMetadata(ctx context.Context, config *ScalerConfig, httpClient *http.Client) (*azurePipelinesMetadata, error) {
 	meta := azurePipelinesMetadata{}
 	meta.targetPipelinesQueueLength = defaultTargetPipelinesQueueLength
 
@@ -90,60 +100,122 @@ func parseAzurePipelinesMetadata(config *ScalerConfig) (*azurePipelinesMetadata,
 		return nil, fmt.Errorf("no personalAccessToken given")
 	}
 
-	if val, ok := config.TriggerMetadata["poolID"]; ok && val != "" {
-		meta.poolID = val
+	if val, ok := config.TriggerMetadata["poolName"]; ok && val != "" {
+		var err error
+		meta.poolID, err = getPoolIDFromName(ctx, val, &meta, httpClient)
+		if err != nil {
+			return nil, err
+		}
 	} else {
-		return nil, fmt.Errorf("no poolID given")
+		if val, ok := config.TriggerMetadata["poolID"]; ok && val != "" {
+			var err error
+			meta.poolID, err = validatePoolID(ctx, val, &meta, httpClient)
+			if err != nil {
+				return nil, err
+			}
+		} else {
+			return nil, fmt.Errorf("no poolName or poolID given")
+		}
 	}
 
 	meta.scalerIndex = config.ScalerIndex
 
 	return &meta, nil
 }
 
-func (s *azurePipelinesScaler) GetMetrics(ctx context.Context, metricName string, metricSelector labels.Selector) ([]external_metrics.ExternalMetricValue, error) {
-	queuelen, err := s.GetAzurePipelinesQueueLength(ctx)
+func getPoolIDFromName(ctx context.Context, poolName string, metadata *azurePipelinesMetadata, httpClient *http.Client) (int, error) {
+	url := fmt.Sprintf("%s/_apis/distributedtask/pools?poolName=%s", metadata.organizationURL, poolName)
+	body, err := getAzurePipelineRequest(ctx, url, metadata, httpClient)
+	if err != nil {
+		return -1, err
+	}
 
+	var result azurePipelinesPoolNameResponse
+	err = json.Unmarshal(body, &result)
 	if err != nil {
-		azurePipelinesLog.Error(err, "error getting pipelines queue length")
-		return []external_metrics.ExternalMetricValue{}, err
+		return -1, err
 	}
 
-	metric := external_metrics.ExternalMetricValue{
-		MetricName: metricName,
-		Value:      *resource.NewQuantity(int64(queuelen), resource.DecimalSI),
-		Timestamp:  metav1.Now(),
+	count := len(result.Value)
+	if count == 0 {
+		return -1, fmt.Errorf("agent pool with name `%s` not found", poolName)
 	}
 
-	return append([]external_metrics.ExternalMetricValue{}, metric), nil
+	if count != 1 {
+		return -1, fmt.Errorf("found %d agent pool with name `%s`", count, poolName)
+	}
+
+	return result.Value[0].ID, nil
 }
 
-func (s *azurePipelinesScaler) GetAzurePipelinesQueueLength(ctx context.Context) (int, error) {
-	url := fmt.Sprintf("%s/_apis/distributedtask/pools/%s/jobrequests", s.metadata.organizationURL, s.metadata.poolID)
-	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+func validatePoolID(ctx context.Context, poolID string, metadata *azurePipelinesMetadata, httpClient *http.Client) (int, error) {
+	url := fmt.Sprintf("%s/_apis/distributedtask/pools?poolID=%s", metadata.organizationURL, poolID)
+	body, err := getAzurePipelineRequest(ctx, url, metadata, httpClient)
+	if err != nil {
+		return -1, fmt.Errorf("agent pool with id `%s` not found", poolID)
+	}
+
+	var result azurePipelinesPoolIDResponse
+	err = json.Unmarshal(body, &result)
 	if err != nil {
 		return -1, err
 	}
 
-	req.SetBasicAuth("PAT", s.metadata.personalAccessToken)
+	return result.ID, nil
+}
 
-	r, err := s.httpClient.Do(req)
+func getAzurePipelineRequest(ctx context.Context, url string, metadata *azurePipelinesMetadata, httpClient *http.Client) ([]byte, error) {
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
 	if err != nil {
-		return -1, err
+		return []byte{}, err
+	}
+
+	req.SetBasicAuth("PAT", metadata.personalAccessToken)
+
+	r, err := httpClient.Do(req)
+	if err != nil {
+		return []byte{}, err
 	}
 
 	b, err := ioutil.ReadAll(r.Body)
 	if err != nil {
-		return -1, err
+		return []byte{}, err
 	}
 	r.Body.Close()
 
 	if !(r.StatusCode >= 200 && r.StatusCode <= 299) {
-		return -1, fmt.Errorf("the Azure DevOps REST API returned error. url: %s status: %d response: %s", url, r.StatusCode, string(b))
+		return []byte{}, fmt.Errorf("the Azure DevOps REST API returned error. url: %s status: %d response: %s", url, r.StatusCode, string(b))
+	}
+
+	return b, nil
+}
+
+func (s *azurePipelinesScaler) GetMetrics(ctx context.Context, metricName string, metricSelector labels.Selector) ([]external_metrics.ExternalMetricValue, error) {
+	queuelen, err := s.GetAzurePipelinesQueueLength(ctx)
+
+	if err != nil {
+		azurePipelinesLog.Error(err, "error getting pipelines queue length")
+		return []external_metrics.ExternalMetricValue{}, err
+	}
+
+	metric := external_metrics.ExternalMetricValue{
+		MetricName: metricName,
+		Value:      *resource.NewQuantity(int64(queuelen), resource.DecimalSI),
+		Timestamp:  metav1.Now(),
+	}
+
+	return append([]external_metrics.ExternalMetricValue{}, metric), nil
+}
+
+func (s *azurePipelinesScaler) GetAzurePipelinesQueueLength(ctx context.Context) (int, error) {
+	url := fmt.Sprintf("%s/_apis/distributedtask/pools/%d/jobrequests", s.metadata.organizationURL, s.metadata.poolID)
+	body, err := getAzurePipelineRequest(ctx, url, s.metadata, s.httpClient)
+	if err != nil {
+		return -1, err
 	}
 
 	var result map[string]interface{}
-	err = json.Unmarshal(b, &result)
+	err = json.Unmarshal(body, &result)
 	if err != nil {
 		return -1, err
 	}
@@ -152,7 +224,7 @@ func (s *azurePipelinesScaler) GetAzurePipelinesQueueLength(ctx context.Context)
 	jobs, ok := result["value"].([]interface{})
 
 	if !ok {
-		return -1, fmt.Errorf("the Azure DevOps REST API result returned no value data. url: %s status: %d", url, r.StatusCode)
+		return -1, fmt.Errorf("the Azure DevOps REST API result returned no value data despite successful code. url: %s", url)
 	}
 
 	for _, value := range jobs {
@@ -169,7 +241,7 @@ func (s *azurePipelinesScaler) GetMetricSpecForScaling(context.Context) []v2beta
 	targetPipelinesQueueLengthQty := resource.NewQuantity(int64(s.metadata.targetPipelinesQueueLength), resource.DecimalSI)
 	externalMetric := &v2beta2.ExternalMetricSource{
 		Metric: v2beta2.MetricIdentifier{
-			Name: GenerateMetricNameWithIndex(s.metadata.scalerIndex, kedautil.NormalizeString(fmt.Sprintf("azure-pipelines-%s", s.metadata.poolID))),
+			Name: GenerateMetricNameWithIndex(s.metadata.scalerIndex, kedautil.NormalizeString(fmt.Sprintf("azure-pipelines-%d", s.metadata.poolID))),
 		},
 		Target: v2beta2.MetricTarget{
 			Type:         v2beta2.AverageValueMetricType,