Data source plugin: Improve error message when plugin has connection issues (#102625)

* Improve data source error message when stackID

* Update comment

* Revert "Update comment"

This reverts commit 48922bc552.

* Revert "Improve data source error message when stackID"

This reverts commit 4bf0a2f7b7.

* Make public messagic configurable based on context

* Update, simplify

* Update

* Update getting stack

* Update pkg/plugins/errors.go

Co-authored-by: Andres Martinez Gotor <andres.martinez@grafana.com>

* Refactor test to test for when context has stack value

* Remove duplicated test

* Fix error checking logic

---------

Co-authored-by: Andres Martinez Gotor <andres.martinez@grafana.com>

pkg/plugins/backendplugin/grpcplugin/client_v2.go

@@ -173,7 +173,7 @@ func (c *ClientV2) QueryData(ctx context.Context, req *backend.QueryDataRequest)
 		}
 
 		if status.Code(err) == codes.Unavailable {
-			return nil, plugins.ErrPluginGrpcConnectionUnavailableBase.Errorf("%v", err)
+			return nil, plugins.ErrPluginGrpcConnectionUnavailableBaseFn(ctx).Errorf("%v", err)
 		}
 
 		if status.Code(err) == codes.ResourceExhausted {

pkg/plugins/errors.go

@@ -1,6 +1,12 @@
 package plugins
 
-import "github.com/grafana/grafana/pkg/apimachinery/errutil"
+import (
+	"context"
+
+	"github.com/grafana/authlib/types"
+	"github.com/grafana/grafana/pkg/apimachinery/errutil"
+	"github.com/grafana/grafana/pkg/apimachinery/identity"
+)
 
 var (
 	errPluginNotRegisteredBase = errutil.NotFound("plugin.notRegistered",
@@ -42,9 +48,13 @@ var (
 		errutil.WithPublicMessage("The response is too large. Please try to reduce the time range or narrow down your query to return fewer data points."),
 		errutil.WithDownstream())
 
-	// ErrPluginGrpcConnectionUnavailableBase error returned when a plugin connection issue occurs.
-	// Exposed as a base error to wrap it with plugin connection issue errors.
-	ErrPluginGrpcConnectionUnavailableBase = errutil.Internal("plugin.connectionUnavailable",
-		errutil.WithPublicMessage("Data source became unavailable during request. Please try again."),
-		errutil.WithDownstream())
+	ErrPluginGrpcConnectionUnavailableBaseFn = func(ctx context.Context) errutil.Base {
+		pubMsg := "Data source became unavailable during request. Please try again."
+		if requester, err := identity.GetRequester(ctx); err == nil && requester != nil {
+			if namespace, err := types.ParseNamespace(requester.GetNamespace()); err == nil && namespace.StackID != 0 {
+				pubMsg += " If the problem persists, please contact customer support."
+			}
+		}
+		return errutil.Internal("plugin.connectionUnavailable", errutil.WithPublicMessage(pubMsg))
+	}
 )

pkg/plugins/errors_test.go

@@ -0,0 +1,58 @@
+package plugins
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/grafana/grafana/pkg/apimachinery/errutil"
+	"github.com/grafana/grafana/pkg/apimachinery/identity"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestErrPluginGrpcConnectionUnavailableBase(t *testing.T) {
+	tests := []struct {
+		name           string
+		ctx            context.Context
+		err            error
+		expectedPublic string
+	}{
+		{
+			name: "without stack ID in context",
+			ctx: identity.WithRequester(context.Background(), &identity.StaticRequester{
+				Namespace: "org-123",
+			}),
+			err:            errors.New("connection failed"),
+			expectedPublic: "Data source became unavailable during request. Please try again.",
+		},
+		{
+			name: "with stack ID in context",
+			ctx: identity.WithRequester(context.Background(), &identity.StaticRequester{
+				Namespace: "stacks-123",
+			}),
+			err:            errors.New("connection failed"),
+			expectedPublic: "Data source became unavailable during request. Please try again. If the problem persists, please contact customer support.",
+		},
+		{
+			name:           "without static requester in context",
+			ctx:            context.Background(),
+			err:            errors.New("connection failed"),
+			expectedPublic: "Data source became unavailable during request. Please try again.",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ErrPluginGrpcConnectionUnavailableBaseFn(tt.ctx).Errorf("%v", tt.err)
+			assert.Error(t, err)
+
+			// Check if it's a Grafana error
+			var grafanaErr errutil.Error
+			assert.ErrorAs(t, err, &grafanaErr)
+
+			// Check the public message
+			publicErr := grafanaErr.Public()
+			assert.Equal(t, tt.expectedPublic, publicErr.Message)
+		})
+	}
+}

pkg/plugins/manager/client/client.go

@@ -35,7 +35,6 @@ var passthroughErrors = []error{
 	plugins.ErrPluginUnavailable,
 	plugins.ErrMethodNotImplemented,
 	plugins.ErrPluginGrpcResourceExhaustedBase,
-	plugins.ErrPluginGrpcConnectionUnavailableBase,
 }
 
 type Service struct {
@@ -66,6 +65,12 @@ func (s *Service) QueryData(ctx context.Context, req *backend.QueryDataRequest)
 			}
 		}
 
+		// If the error is a plugin grpc connection unavailable error, return it directly
+		// This error is created dynamically based on the context, so we need to check for it here
+		if errors.Is(err, plugins.ErrPluginGrpcConnectionUnavailableBaseFn(ctx)) {
+			return nil, err
+		}
+
 		if errors.Is(err, context.Canceled) {
 			return nil, plugins.ErrPluginRequestCanceledErrorBase.Errorf("client: query data request canceled: %w", err)
 		}

pkg/plugins/manager/client/client_test.go

@@ -50,8 +50,8 @@ func TestQueryData(t *testing.T) {
 				shouldPassThrough: false,
 			},
 			{
-				err:               plugins.ErrPluginGrpcConnectionUnavailableBase.Errorf("unavailable"),
-				expectedError:     plugins.ErrPluginGrpcConnectionUnavailableBase.Errorf("unavailable"),
+				err:               plugins.ErrPluginGrpcConnectionUnavailableBaseFn(context.Background()).Errorf("unavailable"),
+				expectedError:     plugins.ErrPluginGrpcConnectionUnavailableBaseFn(context.Background()).Errorf("unavailable"),
 				shouldPassThrough: true,
 			},
 			{