Chore: Code cleaning with unit tests in promlib (#99542)

* update request tests

* remove unused functions

* add unit tests

* remove commented code

* fix unit tests

pkg/promlib/resource/resource.go

@@ -83,15 +83,6 @@ func (r *Resource) Execute(ctx context.Context, req *backend.CallResourceRequest
 	return callResponse, err
 }
 
-func (r *Resource) DetectVersion(ctx context.Context, req *backend.CallResourceRequest) (*backend.CallResourceResponse, error) {
-	newReq := &backend.CallResourceRequest{
-		PluginContext: req.PluginContext,
-		Path:          "/api/v1/status/buildinfo",
-	}
-
-	return r.Execute(ctx, newReq)
-}
-
 func getSelectors(expr string) ([]string, error) {
 	parsed, err := parser.ParseExpr(expr)
 	if err != nil {

pkg/promlib/resource/resource_test.go

@@ -0,0 +1,109 @@
+package resource_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"testing"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/grafana/grafana/pkg/promlib/resource"
+)
+
+type mockRoundTripper struct {
+	Response *http.Response
+	Err      error
+}
+
+func (m *mockRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
+	return m.Response, m.Err
+}
+
+func setup() (*http.Client, backend.DataSourceInstanceSettings, log.Logger) {
+	// Mock HTTP Response
+	mockResponse := &http.Response{
+		StatusCode: 200,
+		Body:       io.NopCloser(bytes.NewReader([]byte(`{"message": "success"}`))),
+		Header:     make(http.Header),
+	}
+
+	// Create a mock RoundTripper
+	mockTransport := &mockRoundTripper{
+		Response: mockResponse,
+	}
+
+	// Create a mock HTTP client using the mock RoundTripper
+	mockClient := &http.Client{
+		Transport: mockTransport,
+	}
+
+	settings := backend.DataSourceInstanceSettings{
+		ID:       1,
+		URL:      "http://mock-server",
+		JSONData: []byte(`{}`),
+	}
+
+	logger := log.DefaultLogger
+
+	return mockClient, settings, logger
+}
+
+func TestNewResource(t *testing.T) {
+	mockClient, settings, logger := setup()
+	res, err := resource.New(mockClient, settings, logger)
+	require.NoError(t, err)
+	assert.NotNil(t, res)
+}
+
+func TestResource_Execute(t *testing.T) {
+	mockClient, settings, logger := setup()
+	res, err := resource.New(mockClient, settings, logger)
+	require.NoError(t, err)
+
+	req := &backend.CallResourceRequest{
+		URL: "/test",
+	}
+	ctx := context.Background()
+
+	resp, err := res.Execute(ctx, req)
+	require.NoError(t, err)
+	assert.NotNil(t, resp)
+}
+
+func TestResource_GetSuggestions(t *testing.T) {
+	mockClient, _, logger := setup()
+	settings := backend.DataSourceInstanceSettings{
+		ID:       1,
+		URL:      "http://localhost:9090",
+		JSONData: []byte(`{"httpMethod": "GET"}`),
+	}
+
+	res, err := resource.New(mockClient, settings, logger)
+	require.NoError(t, err)
+
+	suggestionReq := resource.SuggestionRequest{
+		LabelName: "instance",
+		Queries:   []string{"up"},
+		Start:     "1609459200",
+		End:       "1609462800",
+		Limit:     10,
+	}
+
+	body, err := json.Marshal(suggestionReq)
+	require.NoError(t, err)
+
+	req := &backend.CallResourceRequest{
+		Body: body,
+	}
+	ctx := context.Background()
+
+	resp, err := res.GetSuggestions(ctx, req)
+	require.NoError(t, err)
+	assert.NotNil(t, resp)
+}