Move code to pkg

pkg/provider/base_provider.go

@@ -0,0 +1,105 @@
+package provider
+
+import (
+	"bytes"
+	"strings"
+	"text/template"
+
+	"github.com/BurntSushi/toml"
+	"github.com/Masterminds/sprig"
+	"github.com/containous/traefik/pkg/config"
+	"github.com/containous/traefik/pkg/log"
+	"github.com/containous/traefik/pkg/tls"
+	"github.com/containous/traefik/pkg/types"
+)
+
+// 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() error {
+	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
+}
+
+// CreateConfiguration creates a provider configuration from content using templating.
+func (p *BaseProvider) CreateConfiguration(tmplContent string, funcMap template.FuncMap, templateObjects interface{}) (*config.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 Decodes a *types.Configuration from a content.
+func (p *BaseProvider) DecodeConfiguration(content string) (*config.Configuration, error) {
+	configuration := &config.Configuration{
+		HTTP: &config.HTTPConfiguration{
+			Routers:     make(map[string]*config.Router),
+			Middlewares: make(map[string]*config.Middleware),
+			Services:    make(map[string]*config.Service),
+		},
+		TCP: &config.TCPConfiguration{
+			Routers:  make(map[string]*config.TCPRouter),
+			Services: make(map[string]*config.TCPService),
+		},
+		TLS:        make([]*tls.Configuration, 0),
+		TLSStores:  make(map[string]tls.Store),
+		TLSOptions: make(map[string]tls.TLS),
+	}
+	if _, err := toml.Decode(content, configuration); err != nil {
+		return nil, err
+	}
+	return configuration, nil
+}
+
+func split(sep, s string) []string {
+	return strings.Split(s, sep)
+}