From 0a6e80c6cf1f94420031ba62ad5f309af544f46b Mon Sep 17 00:00:00 2001
From: Matthew Jacobson <matthew.jacobson@grafana.com>
Date: Fri, 2 Jun 2023 16:13:48 -0400
Subject: [PATCH] [v10.0.x] Alerting: Fix provisioned templates being ignored
 by alertmanager (#69488)

Alerting: Fix provisioned templates being ignored by alertmanager (#69485)

* Alerting: Fix provisioned templates being ignored by alertmanager

Template provisioning sets the template in cfg.TemplateFiles while a recent change
made it so that alertmanager reads cfg.AlertmanagerConfig.Templates instead.

This change fixes the issue on both ends, by having provisioning set boths fields and
reverts the change on the alertmanager side so that it uses cfg.TemplateFiles.

(cherry picked from commit c16f1f5e99def9e0136170605368ab33e31e80a1)
---
 pkg/services/ngalert/notifier/alertmanager.go  | 4 ++--
 pkg/services/ngalert/notifier/config.go        | 4 ++--
 pkg/services/ngalert/notifier/config_test.go   | 5 -----
 pkg/services/ngalert/provisioning/templates.go | 5 +++++
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/pkg/services/ngalert/notifier/alertmanager.go b/pkg/services/ngalert/notifier/alertmanager.go
index 8a3090e25e5..a1c7c8b21a6 100644
--- a/pkg/services/ngalert/notifier/alertmanager.go
+++ b/pkg/services/ngalert/notifier/alertmanager.go
@@ -260,13 +260,13 @@ func (am *Alertmanager) applyConfig(cfg *apimodels.PostableUserConfig, rawConfig
 		cfg.TemplateFiles = map[string]string{}
 	}
 	cfg.TemplateFiles["__default__.tmpl"] = alertingTemplates.DefaultTemplateString
-	cfg.AlertmanagerConfig.Templates = append(cfg.AlertmanagerConfig.Templates, "__default__.tmpl")
 
 	// next, we need to make sure we persist the templates to disk.
-	_, templatesChanged, err := PersistTemplates(cfg, am.Base.WorkingDirectory())
+	paths, templatesChanged, err := PersistTemplates(cfg, am.Base.WorkingDirectory())
 	if err != nil {
 		return false, err
 	}
+	cfg.AlertmanagerConfig.Templates = paths
 
 	// If neither the configuration nor templates have changed, we've got nothing to do.
 	if !amConfigChanged && !templatesChanged {
diff --git a/pkg/services/ngalert/notifier/config.go b/pkg/services/ngalert/notifier/config.go
index 10fb03e47ce..7a5454c3b8d 100644
--- a/pkg/services/ngalert/notifier/config.go
+++ b/pkg/services/ngalert/notifier/config.go
@@ -34,7 +34,7 @@ func PersistTemplates(cfg *api.PostableUserConfig, path string) ([]string, bool,
 		}
 
 		file := filepath.Join(path, name)
-		pathSet[file] = struct{}{}
+		pathSet[name] = struct{}{}
 
 		// Check if the template file already exists and if it has changed
 		// We can safely ignore gosec here as we've previously checked the filename is clean
@@ -62,7 +62,7 @@ func PersistTemplates(cfg *api.PostableUserConfig, path string) ([]string, bool,
 	}
 	for _, existingFile := range existingFiles {
 		p := filepath.Join(path, existingFile.Name())
-		_, ok := pathSet[p]
+		_, ok := pathSet[existingFile.Name()]
 		if !ok {
 			templatesChanged = true
 			err := os.Remove(p)
diff --git a/pkg/services/ngalert/notifier/config_test.go b/pkg/services/ngalert/notifier/config_test.go
index 5650ffb3471..6ea12e2c969 100644
--- a/pkg/services/ngalert/notifier/config_test.go
+++ b/pkg/services/ngalert/notifier/config_test.go
@@ -94,11 +94,6 @@ func TestPersistTemplates(t *testing.T) {
 				files[f.Name()] = string(content)
 			}
 
-			// Given we use a temporary directory in tests, we need to prepend the expected paths with it.
-			for i, p := range tt.expectedPaths {
-				tt.expectedPaths[i] = filepath.Join(dir, p)
-			}
-
 			require.Equal(t, tt.expectedError, persistErr)
 			require.ElementsMatch(t, tt.expectedPaths, paths)
 			require.Equal(t, tt.expectedChange, changed)
diff --git a/pkg/services/ngalert/provisioning/templates.go b/pkg/services/ngalert/provisioning/templates.go
index a05bb48105b..0e655224eb1 100644
--- a/pkg/services/ngalert/provisioning/templates.go
+++ b/pkg/services/ngalert/provisioning/templates.go
@@ -53,6 +53,11 @@ func (t *TemplateService) SetTemplate(ctx context.Context, orgID int64, tmpl def
 		revision.cfg.TemplateFiles = map[string]string{}
 	}
 	revision.cfg.TemplateFiles[tmpl.Name] = tmpl.Template
+	tmpls := make([]string, 0, len(revision.cfg.TemplateFiles))
+	for name := range revision.cfg.TemplateFiles {
+		tmpls = append(tmpls, name)
+	}
+	revision.cfg.AlertmanagerConfig.Templates = tmpls
 
 	serialized, err := serializeAlertmanagerConfig(*revision.cfg)
 	if err != nil {