AzureMonitor: Improve errorsource (#93533)

* Improve errorsource

* Fix imports

pkg/tsdb/azuremonitor/utils/utils.go

@@ -3,10 +3,12 @@ package utils
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
+	"github.com/grafana/grafana-plugin-sdk-go/experimental/errorsource"
 	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/types"
 )
 
@@ -25,7 +27,7 @@ func GetFirstSubscriptionOrDefault(ctx context.Context, dsInfo types.DatasourceI
 
 	res, err := dsInfo.Services["Azure Monitor"].HTTPClient.Do(request)
 	if err != nil {
-		return "", fmt.Errorf("failed to retrieve subscriptions: %v", err)
+		return "", errorsource.DownstreamError(fmt.Errorf("failed to retrieve subscriptions: %v", err), false)
 	}
 	defer func() {
 		if err := res.Body.Close(); err != nil {
@@ -39,7 +41,7 @@ func GetFirstSubscriptionOrDefault(ctx context.Context, dsInfo types.DatasourceI
 	}
 
 	if len(subscriptions) == 0 {
-		return "", fmt.Errorf("no subscriptions found: %v", err)
+		return "", errorsource.DownstreamError(fmt.Errorf("no subscriptions found: %v", err), false)
 	}
 
 	return subscriptions[0], nil
@@ -68,3 +70,11 @@ func ParseSubscriptions(res *http.Response, logger log.Logger) ([]string, error)
 
 	return result, nil
 }
+
+func ApplySourceFromError(errorMessage error, err error) error {
+	var sourceError errorsource.Error
+	if errors.As(err, &sourceError) {
+		return errorsource.SourceError(sourceError.Source(), errorMessage, false)
+	}
+	return errorMessage
+}