add support for multiple templates in config

examples/jiralert.yml

@@ -72,4 +72,6 @@ receivers:
 
 
 # File containing template definitions. Required.
-template: jiralert.tmpl
+template:
+- jiralert.tmpl
+- other.tmpl

pkg/config/config.go

@@ -112,7 +112,9 @@ func resolveFilepaths(baseDir string, cfg *Config, logger log.Logger) {
 		return absFp
 	}
 
-	cfg.Template = join(cfg.Template)
+	for i, v := range cfg.Template {
+		cfg.Template[i] = join(v)
+	}
 }
 
 // AutoResolve is the struct used for defining jira resolution state when alert is resolved.
@@ -180,7 +182,7 @@ func (rc *ReceiverConfig) UnmarshalYAML(unmarshal func(interface{}) error) error
 type Config struct {
 	Defaults  *ReceiverConfig   `yaml:"defaults,omitempty" json:"defaults,omitempty"`
 	Receivers []*ReceiverConfig `yaml:"receivers,omitempty" json:"receivers,omitempty"`
-	Template  string            `yaml:"template" json:"template"`
+	Template  []string          `yaml:"template" json:"template"`
 
 	// Catches all undefined fields and must be empty after parsing.
 	XXX map[string]interface{} `yaml:",inline" json:"-"`
@@ -330,7 +332,7 @@ func (c *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {
 		return fmt.Errorf("no receivers defined")
 	}
 
-	if c.Template == "" {
+	if len(c.Template) == 0 {
 		return fmt.Errorf("missing template file")
 	}
 

pkg/config/config_test.go

@@ -78,7 +78,7 @@ receivers:
       customfield_10003: [{"value": "red" }, {"value": "blue" }, {"value": "green" }]
 
 # File containing template definitions. Required.
-template: jiralert.tmpl
+template: ["jiralert.tmpl"]
 `
 
 // Generic test that loads the testConf with no errors.
@@ -144,7 +144,7 @@ type receiverTestConfig struct {
 type testConfig struct {
 	Defaults  *receiverTestConfig   `yaml:"defaults,omitempty"`
 	Receivers []*receiverTestConfig `yaml:"receivers,omitempty"`
-	Template  string                `yaml:"template,omitempty"`
+	Template  []string              `yaml:"template,omitempty"`
 }
 
 // Required Config keys tests.
@@ -155,7 +155,7 @@ func TestMissingConfigKeys(t *testing.T) {
 	var config testConfig
 
 	// No receivers.
-	config = testConfig{Defaults: defaultsConfig, Receivers: []*receiverTestConfig{}, Template: "jiralert.tmpl"}
+	config = testConfig{Defaults: defaultsConfig, Receivers: []*receiverTestConfig{}, Template: []string{"jiralert.tmpl"}}
 	configErrorTestRunner(t, config, "no receivers defined")
 
 	// No template.
@@ -188,7 +188,7 @@ func TestRequiredReceiverConfigKeys(t *testing.T) {
 		config := testConfig{
 			Defaults:  defaultsConfig,
 			Receivers: []*receiverTestConfig{receiverConfig},
-			Template:  "jiratemplate.tmpl",
+			Template:  []string{"jiralert.tmpl"},
 		}
 		configErrorTestRunner(t, config, test.errorMessage)
 	}
@@ -237,7 +237,7 @@ func TestAuthKeysErrors(t *testing.T) {
 		config := testConfig{
 			Defaults:  defaultsConfig,
 			Receivers: []*receiverTestConfig{minimalReceiverTestConfig},
-			Template:  "jiralert.tmpl",
+			Template:  []string{"jiralert.tmpl"},
 		}
 
 		configErrorTestRunner(t, config, test.errorMessage)
@@ -294,7 +294,7 @@ func TestAuthKeysOverrides(t *testing.T) {
 		config := testConfig{
 			Defaults:  defaultsConfig,
 			Receivers: []*receiverTestConfig{receiverConfig},
-			Template:  "jiralert.tmpl",
+			Template:  []string{"jiralert.tmpl"},
 		}
 
 		yamlConfig, err := yaml.Marshal(&config)
@@ -353,7 +353,7 @@ func TestReceiverOverrides(t *testing.T) {
 		config := testConfig{
 			Defaults:  defaultsConfig,
 			Receivers: []*receiverTestConfig{receiverConfig},
-			Template:  "jiralert.tmpl",
+			Template:  []string{"jiralert.tmpl"},
 		}
 
 		yamlConfig, err := yaml.Marshal(&config)
@@ -455,7 +455,7 @@ func TestAutoResolveConfigReceiver(t *testing.T) {
 	config := testConfig{
 		Defaults:  defaultsConfig,
 		Receivers: []*receiverTestConfig{minimalReceiverTestConfig},
-		Template:  "jiralert.tmpl",
+		Template:  []string{"jiralert.tmpl"},
 	}
 
 	configErrorTestRunner(t, config, "bad config in receiver \"test\", 'auto_resolve' was defined with empty 'state' field")
@@ -473,7 +473,7 @@ func TestAutoResolveConfigDefault(t *testing.T) {
 	config := testConfig{
 		Defaults:  defaultsConfig,
 		Receivers: []*receiverTestConfig{minimalReceiverTestConfig},
-		Template:  "jiralert.tmpl",
+		Template:  []string{"jiralert.tmpl"},
 	}
 
 	configErrorTestRunner(t, config, "bad config in defaults section: state cannot be empty")
@@ -503,7 +503,7 @@ func TestStaticLabelsConfigMerge(t *testing.T) {
 		config := testConfig{
 			Defaults:  defaultsConfig,
 			Receivers: []*receiverTestConfig{receiverConfig},
-			Template:  "jiralert.tmpl",
+			Template:  []string{"jiralert.tmpl"},
 		}
 
 		yamlConfig, err := yaml.Marshal(&config)

pkg/template/template.go

@@ -41,6 +41,7 @@ var funcs = template.FuncMap{
 		return strings.Join(s, sep)
 	},
 	"match": regexp.MatchString,
+	"split": strings.Split,
 	"reReplaceAll": func(pattern, repl, text string) string {
 		re := regexp.MustCompile(pattern)
 		return re.ReplaceAllString(text, repl)
@@ -54,9 +55,9 @@ var funcs = template.FuncMap{
 }
 
 // LoadTemplate reads and parses all templates defined in the given file and constructs a jiralert.Template.
-func LoadTemplate(path string, logger log.Logger) (*Template, error) {
+func LoadTemplate(path []string, logger log.Logger) (*Template, error) {
 	level.Debug(logger).Log("msg", "loading templates", "path", path)
-	tmpl, err := template.New("").Option("missingkey=zero").Funcs(funcs).ParseFiles(path)
+	tmpl, err := template.New("").Option("missingkey=zero").Funcs(funcs).ParseFiles(path...)
 	if err != nil {
 		return nil, err
 	}