AzureMonitor: Refactor Log Analytics backend (#87429)

* Remove unneeded error check

* Refactor to reduce cyclomatic complexity

* Add util function for parsing resultformat

* Make use of util

* Remove unneeded types

* Move types to their own file

* Move getApiUrl to utils

* Move traces functions to separate file

- Add separate helper for building trace string queries

* Add helper for determining resources

* Add test for RetrieveResources

* Don't append twice

* Refactor tests

pkg/tsdb/azuremonitor/loganalytics/utils.go

@@ -1,7 +1,12 @@
 package loganalytics
 
 import (
+	"fmt"
+	"regexp"
+	"strings"
+
 	"github.com/grafana/grafana-plugin-sdk-go/data"
+	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/kinds/dataquery"
 )
 
 func AddCustomDataLink(frame data.Frame, dataLink data.DataLink) data.Frame {
@@ -31,3 +36,55 @@ func AddConfigLinks(frame data.Frame, dl string, title *string) data.Frame {
 
 	return frame
 }
+
+func ParseResultFormat(queryResultFormat *dataquery.ResultFormat, queryType dataquery.AzureQueryType) dataquery.ResultFormat {
+	var resultFormat dataquery.ResultFormat
+	if queryResultFormat != nil {
+		resultFormat = *queryResultFormat
+	}
+	if resultFormat == "" {
+		if queryType == dataquery.AzureQueryTypeAzureLogAnalytics {
+			// Default to logs format for logs queries
+			resultFormat = dataquery.ResultFormatLogs
+		}
+		if queryType == dataquery.AzureQueryTypeAzureTraces {
+			// Default to table format for traces queries as many traces may be returned
+			resultFormat = dataquery.ResultFormatTable
+		}
+	}
+	return resultFormat
+}
+
+func getApiURL(resourceOrWorkspace string, isAppInsightsQuery bool) string {
+	matchesResourceURI, _ := regexp.MatchString("^/subscriptions/", resourceOrWorkspace)
+
+	if matchesResourceURI {
+		if isAppInsightsQuery {
+			componentName := resourceOrWorkspace[strings.LastIndex(resourceOrWorkspace, "/")+1:]
+			return fmt.Sprintf("v1/apps/%s/query", componentName)
+		}
+		return fmt.Sprintf("v1%s/query", resourceOrWorkspace)
+	} else {
+		return fmt.Sprintf("v1/workspaces/%s/query", resourceOrWorkspace)
+	}
+}
+
+// Legacy queries only specify a Workspace GUID, which we need to use the old workspace-centric
+// API URL for, and newer queries specifying a resource URI should use resource-centric API.
+// However, legacy workspace queries using a `workspaces()` template variable will be resolved
+// to a resource URI, so they should use the new resource-centric.
+func retrieveResources(query dataquery.AzureLogsQuery) ([]string, string) {
+	resources := []string{}
+	var resourceOrWorkspace string
+	if len(query.Resources) > 0 {
+		resources = query.Resources
+		resourceOrWorkspace = query.Resources[0]
+	} else if query.Resource != nil && *query.Resource != "" {
+		resources = []string{*query.Resource}
+		resourceOrWorkspace = *query.Resource
+	} else if query.Workspace != nil {
+		resourceOrWorkspace = *query.Workspace
+	}
+
+	return resources, resourceOrWorkspace
+}