refactor promethueus package into sub packages (#43634)

pkg/tsdb/prometheus/client/provider.go

@@ -0,0 +1,53 @@
+package client
+
+import (
+	"strings"
+
+	"github.com/grafana/grafana/pkg/tsdb/prometheus/middleware"
+
+	sdkhttpclient "github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
+	"github.com/grafana/grafana/pkg/infra/httpclient"
+	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/prometheus/client_golang/api"
+	apiv1 "github.com/prometheus/client_golang/api/prometheus/v1"
+)
+
+func Create(url string, httpOpts sdkhttpclient.Options, clientProvider httpclient.Provider, jsonData map[string]interface{}, plog log.Logger) (apiv1.API, error) {
+	customParamsMiddleware := middleware.CustomQueryParameters(plog)
+	middlewares := []sdkhttpclient.Middleware{customParamsMiddleware}
+	if shouldForceGet(jsonData) {
+		middlewares = append(middlewares, middleware.ForceHttpGet(plog))
+	}
+	httpOpts.Middlewares = middlewares
+
+	roundTripper, err := clientProvider.GetTransport(httpOpts)
+	if err != nil {
+		return nil, err
+	}
+
+	cfg := api.Config{
+		Address:      url,
+		RoundTripper: roundTripper,
+	}
+
+	client, err := api.NewClient(cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	return apiv1.NewAPI(client), nil
+}
+
+func shouldForceGet(settingsJson map[string]interface{}) bool {
+	methodInterface, exists := settingsJson["httpMethod"]
+	if !exists {
+		return false
+	}
+
+	method, ok := methodInterface.(string)
+	if !ok {
+		return false
+	}
+
+	return strings.ToLower(method) == "get"
+}

pkg/tsdb/prometheus/client/provider_test.go

@@ -0,0 +1,47 @@
+package client
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestForceGet(t *testing.T) {
+	t.Run("With nil jsonOpts, should not force get-method", func(t *testing.T) {
+		var jsonOpts map[string]interface{}
+		require.False(t, shouldForceGet(jsonOpts))
+	})
+
+	t.Run("With empty jsonOpts, should not force get-method", func(t *testing.T) {
+		jsonOpts := make(map[string]interface{})
+		require.False(t, shouldForceGet(jsonOpts))
+	})
+
+	t.Run("With httpMethod=nil, should not not force get-method", func(t *testing.T) {
+		jsonOpts := map[string]interface{}{
+			"httpMethod": nil,
+		}
+		require.False(t, shouldForceGet(jsonOpts))
+	})
+
+	t.Run("With httpMethod=post, should not force get-method", func(t *testing.T) {
+		jsonOpts := map[string]interface{}{
+			"httpMethod": "POST",
+		}
+		require.False(t, shouldForceGet(jsonOpts))
+	})
+
+	t.Run("With httpMethod=get, should force get-method", func(t *testing.T) {
+		jsonOpts := map[string]interface{}{
+			"httpMethod": "get",
+		}
+		require.True(t, shouldForceGet(jsonOpts))
+	})
+
+	t.Run("With httpMethod=GET, should force get-method", func(t *testing.T) {
+		jsonOpts := map[string]interface{}{
+			"httpMethod": "GET",
+		}
+		require.True(t, shouldForceGet(jsonOpts))
+	})
+}