Prometheus: Fix Azure authentication support (#44407)

Re-adding back Azure authentication support to Prometheus datasource 
after the datasource query logic was rewritten from plugin.json routes to 
Go backend.

Ref #35857

pkg/tsdb/prometheus/promclient/provider.go

@@ -4,8 +4,8 @@ import (
 	"strings"
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend"
-
 	"github.com/grafana/grafana/pkg/tsdb/prometheus/middleware"
+	"github.com/grafana/grafana/pkg/util/maputil"
 
 	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
 	"github.com/grafana/grafana/pkg/infra/httpclient"
@@ -16,30 +16,28 @@ import (
 
 type Provider struct {
 	settings       backend.DataSourceInstanceSettings
-	jsonData       JsonData
+	jsonData       map[string]interface{}
+	httpMethod     string
 	clientProvider httpclient.Provider
 	log            log.Logger
 }
 
 func NewProvider(
 	settings backend.DataSourceInstanceSettings,
-	jsonData JsonData,
+	jsonData map[string]interface{},
 	clientProvider httpclient.Provider,
 	log log.Logger,
 ) *Provider {
+	httpMethod, _ := maputil.GetStringOptional(jsonData, "httpMethod")
 	return &Provider{
 		settings:       settings,
 		jsonData:       jsonData,
+		httpMethod:     httpMethod,
 		clientProvider: clientProvider,
 		log:            log,
 	}
 }
 
-type JsonData struct {
-	Method       string `json:"httpMethod"`
-	TimeInterval string `json:"timeInterval"`
-}
-
 func (p *Provider) GetClient(headers map[string]string) (apiv1.API, error) {
 	opts, err := p.settings.HTTPClientOptions()
 	if err != nil {
@@ -54,6 +52,12 @@ func (p *Provider) GetClient(headers map[string]string) (apiv1.API, error) {
 		opts.SigV4.Service = "aps"
 	}
 
+	// Azure authentication
+	err = p.configureAzureAuthentication(opts)
+	if err != nil {
+		return nil, err
+	}
+
 	roundTripper, err := p.clientProvider.GetTransport(opts)
 	if err != nil {
 		return nil, err
@@ -77,7 +81,7 @@ func (p *Provider) middlewares() []sdkhttpclient.Middleware {
 		middleware.CustomQueryParameters(p.log),
 		sdkhttpclient.CustomHeadersMiddleware(),
 	}
-	if strings.ToLower(p.jsonData.Method) == "get" {
+	if strings.ToLower(p.httpMethod) == "get" {
 		middlewares = append(middlewares, middleware.ForceHttpGet(p.log))
 	}
 

pkg/tsdb/prometheus/promclient/provider_azure.go

@@ -0,0 +1,32 @@
+package promclient
+
+import (
+	"fmt"
+
+	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
+	"github.com/grafana/grafana/pkg/tsdb/azuremonitor/azcredentials"
+	"github.com/grafana/grafana/pkg/util/maputil"
+)
+
+func (p *Provider) configureAzureAuthentication(opts sdkhttpclient.Options) error {
+	credentials, err := azcredentials.FromDatasourceData(p.jsonData, p.settings.DecryptedSecureJSONData)
+	if err != nil {
+		err = fmt.Errorf("invalid Azure credentials: %s", err)
+		return err
+	}
+
+	if credentials != nil {
+		opts.CustomOptions["_azureCredentials"] = credentials
+
+		resourceId, err := maputil.GetStringOptional(p.jsonData, "azureEndpointResourceId")
+		if err != nil {
+			return err
+		}
+
+		if resourceId != "" {
+			opts.CustomOptions["azureEndpointResourceId"] = resourceId
+		}
+	}
+
+	return nil
+}

pkg/tsdb/prometheus/promclient/provider_test.go

@@ -135,7 +135,7 @@ func setup(jsonData ...string) *testContext {
 		rawData = []byte(jsonData[0])
 	}
 
-	var jd promclient.JsonData
+	var jd map[string]interface{}
 	_ = json.Unmarshal(rawData, &jd)
 
 	settings := backend.DataSourceInstanceSettings{URL: "test-url", JSONData: rawData}

pkg/tsdb/prometheus/prometheus.go

@@ -16,6 +16,7 @@ import (
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/tracing"
 	"github.com/grafana/grafana/pkg/tsdb/intervalv2"
+	"github.com/grafana/grafana/pkg/util/maputil"
 	apiv1 "github.com/prometheus/client_golang/api/prometheus/v1"
 )
 
@@ -42,7 +43,7 @@ func ProvideService(httpClientProvider httpclient.Provider, tracer tracing.Trace
 
 func newInstanceSettings(httpClientProvider httpclient.Provider) datasource.InstanceFactoryFunc {
 	return func(settings backend.DataSourceInstanceSettings) (instancemgmt.Instance, error) {
-		var jsonData promclient.JsonData
+		var jsonData map[string]interface{}
 		err := json.Unmarshal(settings.JSONData, &jsonData)
 		if err != nil {
 			return nil, fmt.Errorf("error reading settings: %w", err)
@@ -54,10 +55,15 @@ func newInstanceSettings(httpClientProvider httpclient.Provider) datasource.Inst
 			return nil, err
 		}
 
+		timeInterval, err := maputil.GetStringOptional(jsonData, "timeInterval")
+		if err != nil {
+			return nil, err
+		}
+
 		mdl := DatasourceInfo{
 			ID:           settings.ID,
 			URL:          settings.URL,
-			TimeInterval: jsonData.TimeInterval,
+			TimeInterval: timeInterval,
 			getClient:    pc.GetClient,
 		}
 

pkg/util/maputil/maputil.go

@@ -0,0 +1,73 @@
+package maputil
+
+import "fmt"
+
+func GetMap(obj map[string]interface{}, key string) (map[string]interface{}, error) {
+	if untypedValue, ok := obj[key]; ok {
+		if value, ok := untypedValue.(map[string]interface{}); ok {
+			return value, nil
+		} else {
+			err := fmt.Errorf("the field '%s' should be an object", key)
+			return nil, err
+		}
+	} else {
+		err := fmt.Errorf("the field '%s' should be set", key)
+		return nil, err
+	}
+}
+
+func GetBool(obj map[string]interface{}, key string) (bool, error) {
+	if untypedValue, ok := obj[key]; ok {
+		if value, ok := untypedValue.(bool); ok {
+			return value, nil
+		} else {
+			err := fmt.Errorf("the field '%s' should be a bool", key)
+			return false, err
+		}
+	} else {
+		err := fmt.Errorf("the field '%s' should be set", key)
+		return false, err
+	}
+}
+
+func GetBoolOptional(obj map[string]interface{}, key string) (bool, error) {
+	if untypedValue, ok := obj[key]; ok {
+		if value, ok := untypedValue.(bool); ok {
+			return value, nil
+		} else {
+			err := fmt.Errorf("the field '%s' should be a bool", key)
+			return false, err
+		}
+	} else {
+		// Value optional, not error
+		return false, nil
+	}
+}
+
+func GetString(obj map[string]interface{}, key string) (string, error) {
+	if untypedValue, ok := obj[key]; ok {
+		if value, ok := untypedValue.(string); ok {
+			return value, nil
+		} else {
+			err := fmt.Errorf("the field '%s' should be a string", key)
+			return "", err
+		}
+	} else {
+		err := fmt.Errorf("the field '%s' should be set", key)
+		return "", err
+	}
+}
+
+func GetStringOptional(obj map[string]interface{}, key string) (string, error) {
+	if untypedValue, ok := obj[key]; ok {
+		if value, ok := untypedValue.(string); ok {
+			return value, nil
+		} else {
+			err := fmt.Errorf("the field '%s' should be a string", key)
+			return "", err
+		}
+	} else {
+		// Value optional, not error
+		return "", nil
+	}
+}