Added support for templates to file provider

configuration/configuration.go

@@ -239,8 +239,8 @@ func (gc *GlobalConfiguration) SetEffectiveConfiguration(configFile string) {
 	}
 
 	// Try to fallback to traefik config file in case the file provider is enabled
-	// but has no file name configured.
-	if gc.File != nil && len(gc.File.Filename) == 0 {
+	// but has no file name configured and is not in a directory mode.
+	if gc.File != nil && len(gc.File.Filename) == 0 && len(gc.File.Directory) == 0 {
 		if len(configFile) > 0 {
 			gc.File.Filename = configFile
 		} else {

configuration/configuration_test.go

@@ -77,6 +77,11 @@ func TestSetEffectiveConfigurationFileProviderFilename(t *testing.T) {
 			fileProvider:             &file.Provider{BaseProvider: provider.BaseProvider{Filename: "other.toml"}},
 			wantFileProviderFilename: "other.toml",
 		},
+		{
+			desc:                     "directory for file provider given",
+			fileProvider:             &file.Provider{Directory: "/"},
+			wantFileProviderFilename: "",
+		},
 	}
 
 	for _, test := range tests {

provider/file/file.go

@@ -7,8 +7,8 @@ import (
 	"path"
 	"path/filepath"
 	"strings"
+	"text/template"
 
-	"github.com/BurntSushi/toml"
 	"github.com/containous/traefik/log"
 	"github.com/containous/traefik/provider"
 	"github.com/containous/traefik/safe"
@@ -56,9 +56,9 @@ func (p *Provider) Provide(configurationChan chan<- types.ConfigMessage, pool *s
 // and returns a 'Configuration' object
 func (p *Provider) BuildConfiguration() (*types.Configuration, error) {
 	if p.Directory != "" {
-		return loadFileConfigFromDirectory(p.Directory, nil)
+		return p.loadFileConfigFromDirectory(p.Directory, nil)
 	}
-	return loadFileConfig(p.Filename)
+	return p.loadFileConfig(p.Filename)
 }
 
 func (p *Provider) addWatcher(pool *safe.Pool, directory string, configurationChan chan<- types.ConfigMessage, callback func(chan<- types.ConfigMessage, fsnotify.Event)) error {
@@ -125,18 +125,36 @@ func sendConfigToChannel(configurationChan chan<- types.ConfigMessage, configura
 	}
 }
 
-func loadFileConfig(filename string) (*types.Configuration, error) {
-	configuration := &types.Configuration{
-		Frontends: make(map[string]*types.Frontend),
-		Backends:  make(map[string]*types.Backend),
+func readFile(filename string) (string, error) {
+	if len(filename) > 0 {
+		buf, err := ioutil.ReadFile(filename)
+		if err != nil {
+			return "", err
+		}
+		return string(buf), nil
 	}
-	if _, err := toml.DecodeFile(filename, configuration); err != nil {
-		return nil, fmt.Errorf("error reading configuration file: %s", err)
-	}
-	return configuration, nil
+	return "", fmt.Errorf("invalid filename: %s", filename)
 }
 
-func loadFileConfigFromDirectory(directory string, configuration *types.Configuration) (*types.Configuration, error) {
+func (p *Provider) loadFileConfig(filename string) (*types.Configuration, error) {
+	fileContent, err := readFile(filename)
+	if err != nil {
+		return nil, fmt.Errorf("error reading configuration file: %s - %s", filename, err)
+	}
+	configuration, err := p.CreateConfiguration(fileContent, template.FuncMap{}, false)
+	if err != nil {
+		return nil, err
+	}
+	if configuration == nil || configuration.Backends == nil && configuration.Frontends == nil && configuration.TLS == nil {
+		configuration = &types.Configuration{
+			Frontends: make(map[string]*types.Frontend),
+			Backends:  make(map[string]*types.Backend),
+		}
+	}
+	return configuration, err
+}
+
+func (p *Provider) loadFileConfigFromDirectory(directory string, configuration *types.Configuration) (*types.Configuration, error) {
 	fileList, err := ioutil.ReadDir(directory)
 
 	if err != nil {
@@ -154,17 +172,17 @@ func loadFileConfigFromDirectory(directory string, configuration *types.Configur
 	for _, item := range fileList {
 
 		if item.IsDir() {
-			configuration, err = loadFileConfigFromDirectory(filepath.Join(directory, item.Name()), configuration)
+			configuration, err = p.loadFileConfigFromDirectory(filepath.Join(directory, item.Name()), configuration)
 			if err != nil {
 				return configuration, fmt.Errorf("unable to load content configuration from subdirectory %s: %v", item, err)
 			}
 			continue
-		} else if !strings.HasSuffix(item.Name(), ".toml") {
+		} else if !strings.HasSuffix(item.Name(), ".toml") && !strings.HasSuffix(item.Name(), ".tmpl") {
 			continue
 		}
 
 		var c *types.Configuration
-		c, err = loadFileConfig(path.Join(directory, item.Name()))
+		c, err = p.loadFileConfig(path.Join(directory, item.Name()))
 
 		if err != nil {
 			return configuration, err

provider/file/file_test.go

@@ -276,10 +276,13 @@ func createSubDir(t *testing.T, rootDir, dir string) string {
 
 // createFrontendConfiguration Helper
 func createFrontendConfiguration(n int) string {
-	conf := "[frontends]\n"
+	conf := "{{$home := env \"HOME\"}}\n[frontends]\n"
 	for i := 1; i <= n; i++ {
-		conf += fmt.Sprintf(`  [frontends.frontend%[1]d]
+		conf += fmt.Sprintf(`  [frontends."frontend%[1]d"]
   backend = "backend%[1]d"
+`, i)
+		conf += fmt.Sprintf(`    [frontends."frontend%[1]d".headers]
+    "PublicKey" = "{{$home}}/pub.key"
 `, i)
 	}
 	return conf

provider/provider.go

@@ -50,8 +50,17 @@ func (p *BaseProvider) MatchConstraints(tags []string) (bool, *types.Constraint)
 	return true, nil
 }
 
-// GetConfiguration return the provider configuration using templating
-func (p *BaseProvider) GetConfiguration(defaultTemplateFile string, funcMap template.FuncMap, templateObjects interface{}) (*types.Configuration, error) {
+// GetConfiguration return the provider configuration from default template (file or content) or overrode template file
+func (p *BaseProvider) GetConfiguration(defaultTemplate string, funcMap template.FuncMap, templateObjects interface{}) (*types.Configuration, error) {
+	tmplContent, err := p.getTemplateContent(defaultTemplate)
+	if err != nil {
+		return nil, err
+	}
+	return p.CreateConfiguration(tmplContent, funcMap, templateObjects)
+}
+
+// CreateConfiguration create a provider configuration from content using templating
+func (p *BaseProvider) CreateConfiguration(tmplContent string, funcMap template.FuncMap, templateObjects interface{}) (*types.Configuration, error) {
 	configuration := new(types.Configuration)
 
 	var defaultFuncMap = sprig.TxtFuncMap()
@@ -65,12 +74,7 @@ func (p *BaseProvider) GetConfiguration(defaultTemplateFile string, funcMap temp
 
 	tmpl := template.New(p.Filename).Funcs(defaultFuncMap)
 
-	tmplContent, err := p.getTemplateContent(defaultTemplateFile)
-	if err != nil {
-		return nil, err
-	}
-
-	_, err = tmpl.Parse(tmplContent)
+	_, err := tmpl.Parse(tmplContent)
 	if err != nil {
 		return nil, err
 	}
@@ -83,7 +87,8 @@ func (p *BaseProvider) GetConfiguration(defaultTemplateFile string, funcMap temp
 
 	var renderedTemplate = buffer.String()
 	if p.DebugLogGeneratedTemplate {
-		log.Debugf("Rendering results of %s:\n%s", defaultTemplateFile, renderedTemplate)
+		log.Debugf("Template content: %s", tmplContent)
+		log.Debugf("Rendering results: %s", renderedTemplate)
 	}
 	if _, err := toml.Decode(renderedTemplate, configuration); err != nil {
 		return nil, err