coder · dannykopping · May 14, 2025 · Apr 25, 2025 · Apr 25, 2025 · Apr 25, 2025
diff --git a/coderd/coderd.go b/coderd/coderd.go
@@ -1790,6 +1790,7 @@ func (api *API) CreateInMemoryTaggedProvisionerDaemon(dialCtx context.Context, n
 			Clock:               api.Clock,
 		},
 		api.NotificationsEnqueuer,
+		&api.PrebuildsReconciler,
 	)
 	if err != nil {
 		return nil, err

diff --git a/coderd/database/dbauthz/dbauthz.go b/coderd/database/dbauthz/dbauthz.go
@@ -2524,6 +2524,13 @@ func (q *querier) GetTemplateParameterInsights(ctx context.Context, arg database
 	return q.db.GetTemplateParameterInsights(ctx, arg)
 }
 
+func (q *querier) GetTemplatePresetsByID(ctx context.Context, id uuid.UUID) (database.TemplateVersionPreset, error) {
+	if err := q.authorizeContext(ctx, policy.ActionRead, rbac.ResourceTemplate.All()); err != nil {
+		return database.TemplateVersionPreset{}, err
+	}
+	return q.db.GetTemplatePresetsByID(ctx, id)
+}
+
 func (q *querier) GetTemplatePresetsWithPrebuilds(ctx context.Context, templateID uuid.NullUUID) ([]database.GetTemplatePresetsWithPrebuildsRow, error) {
 	// GetTemplatePresetsWithPrebuilds retrieves template versions with configured presets and prebuilds.
 	// Presets and prebuilds are part of the template, so if you can access templates - you can access them as well.

diff --git a/coderd/database/dbauthz/dbauthz_test.go b/coderd/database/dbauthz/dbauthz_test.go
@@ -4873,6 +4873,27 @@ func (s *MethodTestSuite) TestPrebuilds() {
 			Asserts(rbac.ResourceTemplate.All(), policy.ActionRead).
 			ErrorsWithInMemDB(dbmem.ErrUnimplemented)
 	}))
+	s.Run("GetTemplatePresetsByID", s.Subtest(func(db database.Store, check *expects) {
+		org := dbgen.Organization(s.T(), db, database.Organization{})
+		user := dbgen.User(s.T(), db, database.User{})
+		t := dbgen.Template(s.T(), db, database.Template{
+			OrganizationID: org.ID,
+			CreatedBy:      user.ID,
+		})
+		tv := dbgen.TemplateVersion(s.T(), db, database.TemplateVersion{
+			TemplateID:     uuid.NullUUID{UUID: t.ID, Valid: true},
+			OrganizationID: org.ID,
+			CreatedBy:      user.ID,
+		})
+		preset := dbgen.Preset(s.T(), db, database.InsertPresetParams{
+			TemplateVersionID: tv.ID,
+			Name:              "my-preset",
+			DesiredInstances:  sql.NullInt32{Int32: 1, Valid: true},
+		})
+		check.Args(preset.ID).
+			Asserts(rbac.ResourceTemplate.All(), policy.ActionRead).
+			ErrorsWithInMemDB(dbmem.ErrUnimplemented)
+	}))
 	s.Run("GetPresetByID", s.Subtest(func(db database.Store, check *expects) {
 		org := dbgen.Organization(s.T(), db, database.Organization{})
 		user := dbgen.User(s.T(), db, database.User{})

diff --git a/coderd/database/dbmem/dbmem.go b/coderd/database/dbmem/dbmem.go
@@ -6072,6 +6072,10 @@ func (q *FakeQuerier) GetTemplateParameterInsights(ctx context.Context, arg data
 	return rows, nil
 }
 
+func (q *FakeQuerier) GetTemplatePresetsByID(ctx context.Context, id uuid.UUID) (database.TemplateVersionPreset, error) {
+	return database.TemplateVersionPreset{}, ErrUnimplemented
+}
+
 func (*FakeQuerier) GetTemplatePresetsWithPrebuilds(_ context.Context, _ uuid.NullUUID) ([]database.GetTemplatePresetsWithPrebuildsRow, error) {
 	return nil, ErrUnimplemented
 }

diff --git a/coderd/database/dbmetrics/querymetrics.go b/coderd/database/dbmetrics/querymetrics.go
diff --git a/coderd/database/dbmock/dbmock.go b/coderd/database/dbmock/dbmock.go
diff --git a/coderd/database/migrations/000320_resource_replacements_notification.down.sql b/coderd/database/migrations/000320_resource_replacements_notification.down.sql
@@ -0,0 +1 @@
+DELETE FROM notification_templates WHERE id = '89d9745a-816e-4695-a17f-3d0a229e2b8d';
diff --git a/coderd/database/migrations/000320_resource_replacements_notification.up.sql b/coderd/database/migrations/000320_resource_replacements_notification.up.sql
@@ -0,0 +1,34 @@
+INSERT INTO notification_templates
+	(id, name, title_template, body_template, "group", actions)
+VALUES ('89d9745a-816e-4695-a17f-3d0a229e2b8d',
+		'Prebuilt Workspace Resource Replaced',
+		E'There might be a problem with a recently claimed prebuilt workspace',
+		$$
+Workspace **{{.Labels.workspace}}** was claimed from a prebuilt workspace by **{{.Labels.claimant}}**.
+
+During the claim, Terraform destroyed and recreated the following resources
+because one or more immutable attributes changed:
+
+{{range $resource, $paths := .Data.replacements -}}
+- _{{ $resource }}_  was replaced due to changes to _{{ $paths }}_
+{{end}}
+
+When Terraform must change an immutable attribute, it replaces the entire resource.
+If you’re using prebuilds to speed up provisioning, unexpected replacements will slow down
+workspace startup—even when claiming a prebuilt environment.
+
+For tips on preventing replacements and improving claim performance, see [this guide](https://coder.com/docs/admin/templates/extending-templates/prebuilt-workspaces.md#preventing-resource-replacement).
+
+NOTE: this prebuilt workspace used the **{{.Labels.preset}}** preset.
+$$,
+		'Template Events',
+		'[
+		{
+			"label": "View workspace build",
+			"url": "{{base_url}}/@{{.Labels.claimant}}/{{.Labels.workspace}}/builds/{{.Labels.workspace_build_num}}"
+		},
+		{
+			"label": "View template version",
+			"url": "{{base_url}}/templates/{{.Labels.org}}/{{.Labels.template}}/versions/{{.Labels.template_version}}"
+		}
+	]'::jsonb);
diff --git a/coderd/database/querier.go b/coderd/database/querier.go
diff --git a/coderd/database/queries.sql.go b/coderd/database/queries.sql.go
diff --git a/coderd/database/queries/prebuilds.sql b/coderd/database/queries/prebuilds.sql
@@ -42,6 +42,11 @@ FROM templates t
 WHERE tvp.desired_instances IS NOT NULL -- Consider only presets that have a prebuild configuration.
 	AND (t.id = sqlc.narg('template_id')::uuid OR sqlc.narg('template_id') IS NULL);
 
+-- name: GetTemplatePresetsByID :one
+SELECT *
+FROM template_version_presets
+WHERE id = $1;
+
 -- name: GetRunningPrebuiltWorkspaces :many
 SELECT
 		p.id,

diff --git a/coderd/notifications/enqueuer.go b/coderd/notifications/enqueuer.go
@@ -50,7 +50,7 @@ type StoreEnqueuer struct {
 }
 
 // NewStoreEnqueuer creates an Enqueuer implementation which can persist notification messages in the store.
-func NewStoreEnqueuer(cfg codersdk.NotificationsConfig, store Store, helpers template.FuncMap, log slog.Logger, clock quartz.Clock) (*StoreEnqueuer, error) {
+func NewStoreEnqueuer(cfg codersdk.NotificationsConfig, store Store, helpers template.FuncMap, log slog.Logger, clock quartz.Clock) (Enqueuer, error) {
 	var method database.NotificationMethod
 	// TODO(DanielleMaywood):
 	// Currently we do not want to allow setting `inbox` as the default notification method.
@@ -203,7 +203,7 @@ func (s *StoreEnqueuer) buildPayload(metadata database.FetchNewMessageMetadataRo
 type NoopEnqueuer struct{}
 
 // NewNoopEnqueuer builds a NoopEnqueuer which is used to fulfill the contract for enqueuing notifications, if ExperimentNotifications is not set.
-func NewNoopEnqueuer() *NoopEnqueuer {
+func NewNoopEnqueuer() Enqueuer {
 	return &NoopEnqueuer{}
 }
 

diff --git a/coderd/notifications/events.go b/coderd/notifications/events.go
@@ -39,6 +39,7 @@ var (
 	TemplateTemplateDeprecated = uuid.MustParse("f40fae84-55a2-42cd-99fa-b41c1ca64894")
 
 	TemplateWorkspaceBuildsFailedReport = uuid.MustParse("34a20db2-e9cc-4a93-b0e4-8569699d7a00")
+	TemplateWorkspaceResourceReplaced   = uuid.MustParse("89d9745a-816e-4695-a17f-3d0a229e2b8d")
 )
 
 // Notification-related events.

diff --git a/coderd/notifications/notifications_test.go b/coderd/notifications/notifications_test.go
@@ -35,6 +35,9 @@ import (
 	"golang.org/x/xerrors"
 
 	"cdr.dev/slog"
+	"github.com/coder/quartz"
+	"github.com/coder/serpent"
+
 	"github.com/coder/coder/v2/coderd/coderdtest"
 	"github.com/coder/coder/v2/coderd/database"
 	"github.com/coder/coder/v2/coderd/database/dbauthz"
@@ -48,8 +51,6 @@ import (
 	"github.com/coder/coder/v2/coderd/util/syncmap"
 	"github.com/coder/coder/v2/codersdk"
 	"github.com/coder/coder/v2/testutil"
-	"github.com/coder/quartz"
-	"github.com/coder/serpent"
 )
 
 // updateGoldenFiles is a flag that can be set to update golden files.
@@ -1226,6 +1227,29 @@ func TestNotificationTemplates_Golden(t *testing.T) {
 				Labels:       map[string]string{},
 			},
 		},
+		{
+			name: "TemplateWorkspaceResourceReplaced",
+			id:   notifications.TemplateWorkspaceResourceReplaced,
+			payload: types.MessagePayload{
+				UserName:     "Bobby",
+				UserEmail:    "bobby@coder.com",
+				UserUsername: "bobby",
+				Labels: map[string]string{
+					"org":                 "cern",
+					"workspace":           "my-workspace",
+					"workspace_build_num": "2",
+					"template":            "docker",
+					"template_version":    "angry_torvalds",
+					"preset":              "particle-accelerator",
+					"claimant":            "prebuilds-claimer",
+				},
+				Data: map[string]any{
+					"replacements": map[string]string{
+						"docker_container[0]": "env, hostname",
+					},
+				},
+			},
+		},
 	}
 
 	// We must have a test case for every notification_template. This is enforced below:

diff --git a/coderd/notifications/notificationstest/fake_enqueuer.go b/coderd/notifications/notificationstest/fake_enqueuer.go
@@ -9,6 +9,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/coder/coder/v2/coderd/database/dbauthz"
+	"github.com/coder/coder/v2/coderd/notifications"
 	"github.com/coder/coder/v2/coderd/rbac"
 	"github.com/coder/coder/v2/coderd/rbac/policy"
 )
@@ -19,6 +20,12 @@ type FakeEnqueuer struct {
 	sent       []*FakeNotification
 }
 
+var _ notifications.Enqueuer = &FakeEnqueuer{}
+
+func NewFakeEnqueuer() notifications.Enqueuer {
+	return &FakeEnqueuer{}
+}
+
 type FakeNotification struct {
 	UserID, TemplateID uuid.UUID
 	Labels             map[string]string
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		DELETE FROM notification_templates WHERE id = '89d9745a-816e-4695-a17f-3d0a229e2b8d';