Dynamic Configuration Refactoring

provider/provider.go

@@ -1,16 +1,7 @@
 package provider
 
 import (
-	"bytes"
-	"io/ioutil"
-	"strings"
-	"text/template"
-	"unicode"
-
-	"github.com/BurntSushi/toml"
-	"github.com/Masterminds/sprig"
-	"github.com/containous/traefik/autogen/gentemplates"
-	"github.com/containous/traefik/log"
+	"github.com/containous/traefik/config"
 	"github.com/containous/traefik/safe"
 	"github.com/containous/traefik/types"
 )
@@ -19,131 +10,6 @@ import (
 type Provider interface {
 	// Provide allows the provider to provide configurations to traefik
 	// using the given configuration channel.
-	Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool) error
+	Provide(configurationChan chan<- config.Message, pool *safe.Pool) error
 	Init(constraints types.Constraints) error
 }
-
-// BaseProvider should be inherited by providers
-type BaseProvider struct {
-	Watch                     bool              `description:"Watch provider" export:"true"`
-	Filename                  string            `description:"Override default configuration template. For advanced users :)" export:"true"`
-	Constraints               types.Constraints `description:"Filter services by constraint, matching with Traefik tags." export:"true"`
-	Trace                     bool              `description:"Display additional provider logs (if available)." export:"true"`
-	DebugLogGeneratedTemplate bool              `description:"Enable debug logging of generated configuration template." export:"true"`
-}
-
-// Init for compatibility reason the BaseProvider implements an empty Init
-func (p *BaseProvider) Init(constraints types.Constraints) error {
-	p.Constraints = append(p.Constraints, constraints...)
-	return nil
-}
-
-// MatchConstraints must match with EVERY single constraint
-// returns first constraint that do not match or nil
-func (p *BaseProvider) MatchConstraints(tags []string) (bool, *types.Constraint) {
-	// if there is no tags and no constraints, filtering is disabled
-	if len(tags) == 0 && len(p.Constraints) == 0 {
-		return true, nil
-	}
-
-	for _, constraint := range p.Constraints {
-		// xor: if ok and constraint.MustMatch are equal, then no tag is currently matching with the constraint
-		if ok := constraint.MatchConstraintWithAtLeastOneTag(tags); ok != constraint.MustMatch {
-			return false, constraint
-		}
-	}
-
-	// If no constraint or every constraints matching
-	return true, nil
-}
-
-// 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) {
-	var defaultFuncMap = sprig.TxtFuncMap()
-	// tolower is deprecated in favor of sprig's lower function
-	defaultFuncMap["tolower"] = strings.ToLower
-	defaultFuncMap["normalize"] = Normalize
-	defaultFuncMap["split"] = split
-	for funcID, funcElement := range funcMap {
-		defaultFuncMap[funcID] = funcElement
-	}
-
-	tmpl := template.New(p.Filename).Funcs(defaultFuncMap)
-
-	_, err := tmpl.Parse(tmplContent)
-	if err != nil {
-		return nil, err
-	}
-
-	var buffer bytes.Buffer
-	err = tmpl.Execute(&buffer, templateObjects)
-	if err != nil {
-		return nil, err
-	}
-
-	var renderedTemplate = buffer.String()
-	if p.DebugLogGeneratedTemplate {
-		log.Debugf("Template content: %s", tmplContent)
-		log.Debugf("Rendering results: %s", renderedTemplate)
-	}
-	return p.DecodeConfiguration(renderedTemplate)
-}
-
-// DecodeConfiguration Decode a *types.Configuration from a content
-func (p *BaseProvider) DecodeConfiguration(content string) (*types.Configuration, error) {
-	configuration := new(types.Configuration)
-	if _, err := toml.Decode(content, configuration); err != nil {
-		return nil, err
-	}
-	return configuration, nil
-}
-
-func (p *BaseProvider) getTemplateContent(defaultTemplateFile string) (string, error) {
-	if len(p.Filename) > 0 {
-		buf, err := ioutil.ReadFile(p.Filename)
-		if err != nil {
-			return "", err
-		}
-		return string(buf), nil
-	}
-
-	if strings.HasSuffix(defaultTemplateFile, ".tmpl") {
-		buf, err := gentemplates.Asset(defaultTemplateFile)
-		if err != nil {
-			return "", err
-		}
-		return string(buf), nil
-	}
-
-	return defaultTemplateFile, nil
-}
-
-func split(sep, s string) []string {
-	return strings.Split(s, sep)
-}
-
-// Normalize transform a string that work with the rest of traefik
-// Replace '.' with '-' in quoted keys because of this issue https://github.com/BurntSushi/toml/issues/78
-func Normalize(name string) string {
-	fargs := func(c rune) bool {
-		return !unicode.IsLetter(c) && !unicode.IsNumber(c)
-	}
-	// get function
-	return strings.Join(strings.FieldsFunc(name, fargs), "-")
-}
-
-// ReverseStringSlice invert the order of the given slice of string
-func ReverseStringSlice(slice *[]string) {
-	for i, j := 0, len(*slice)-1; i < j; i, j = i+1, j-1 {
-		(*slice)[i], (*slice)[j] = (*slice)[j], (*slice)[i]
-	}
-}