feat: Add defaultFuncMap to template

provider/provider.go

@@ -58,7 +58,19 @@ func (p *BaseProvider) getConfiguration(defaultTemplateFile string, funcMap temp
 		err error
 	)
 	configuration := new(types.Configuration)
-	tmpl := template.New(p.Filename).Funcs(funcMap)
+	var defaultFuncMap = template.FuncMap{
+		"replace":   replace,
+		"tolower":   strings.ToLower,
+		"normalize": normalize,
+		"split":     split,
+		"contains":  contains,
+	}
+
+	for funcID, funcElement := range funcMap {
+		defaultFuncMap[funcID] = funcElement
+	}
+
+	tmpl := template.New(p.Filename).Funcs(defaultFuncMap)
 	if len(p.Filename) > 0 {
 		buf, err = ioutil.ReadFile(p.Filename)
 		if err != nil {
@@ -93,6 +105,14 @@ func replace(s1 string, s2 string, s3 string) string {
 	return strings.Replace(s3, s1, s2, -1)
 }
 
+func contains(substr, s string) bool {
+	return strings.Contains(s, substr)
+}
+
+func split(sep, s string) []string {
+	return strings.Split(s, sep)
+}
+
 func normalize(name string) string {
 	fargs := func(c rune) bool {
 		return !unicode.IsLetter(c) && !unicode.IsNumber(c)

provider/provider_test.go

@@ -325,3 +325,58 @@ func TestMatchingConstraints(t *testing.T) {
 		}
 	}
 }
+
+func TestDefaultFuncMap(t *testing.T) {
+	templateFile, err := ioutil.TempFile("", "provider-configuration")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(templateFile.Name())
+	data := []byte(`
+  [backends]
+  [backends.{{ "backend-1" | replace  "-" "" }}]
+    [backends.{{ "BACKEND1" | tolower }}.circuitbreaker]
+      expression = "NetworkErrorRatio() > 0.5"
+    [backends.servers.server1]
+    url = "http://172.17.0.2:80"
+    weight = 10
+    [backends.backend1.servers.server2]
+    url = "http://172.17.0.3:80"
+    weight = 1
+
+[frontends]
+  [frontends.{{normalize "frontend/1"}}]
+  {{ $backend := "backend1/test/value" | split  "/" }}
+  {{ $backendid := index $backend 1 }}
+  {{ if "backend1" | contains "backend" }}
+  backend = "backend1"
+  {{end}}
+  passHostHeader = true
+    [frontends.frontend-1.routes.test_2]
+    rule = "Path"
+    value = "/test"`)
+	err = ioutil.WriteFile(templateFile.Name(), data, 0700)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	provider := &myProvider{
+		BaseProvider{
+			Filename: templateFile.Name(),
+		},
+		nil,
+	}
+	configuration, err := provider.getConfiguration(templateFile.Name(), nil, nil)
+	if err != nil {
+		t.Fatalf("Shouldn't have error out, got %v", err)
+	}
+	if configuration == nil {
+		t.Fatalf("Configuration should not be nil, but was")
+	}
+	if _, ok := configuration.Backends["backend1"]; !ok {
+		t.Fatalf("backend1 should exists, but it not")
+	}
+	if _, ok := configuration.Frontends["frontend-1"]; !ok {
+		t.Fatalf("Frontend frontend-1 should exists, but it not")
+	}
+}