traefik/provider/provider.go

105 lines
3 KiB
Go

package provider
import (
"bytes"
"io/ioutil"
"strings"
"text/template"
"unicode"
"github.com/BurntSushi/toml"
"github.com/containous/traefik/autogen"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
)
// Provider defines methods of a provider.
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, constraints []*types.Constraint) error
}
// BaseProvider should be inherited by providers
type BaseProvider struct {
Watch bool `description:"Watch provider"`
Filename string `description:"Override default configuration template. For advanced users :)"`
Constraints []*types.Constraint `description:"Filter services by constraint, matching with Traefik tags."`
}
// MatchConstraints must match with EVERY single contraint
// returns first constraint that do not match or nil
// returns errors for future use (regex)
func (p *BaseProvider) MatchConstraints(tags []string) (bool, *types.Constraint, error) {
// if there is no tags and no contraints, filtering is disabled
if len(tags) == 0 && len(p.Constraints) == 0 {
return true, nil, nil
}
for _, constraint := range p.Constraints {
if ok := constraint.MatchConstraintWithAtLeastOneTag(tags); xor(ok == true, constraint.MustMatch == true) {
return false, constraint, nil
}
}
// If no constraint or every constraints matching
return true, nil, nil
>>>>>>> e844462... feat(constraints): Implementation of constraints (cmd + toml + matching functions), implementation proposal with consul
}
func (p *BaseProvider) getConfiguration(defaultTemplateFile string, funcMap template.FuncMap, templateObjects interface{}) (*types.Configuration, error) {
var (
buf []byte
err error
)
configuration := new(types.Configuration)
tmpl := template.New(p.Filename).Funcs(funcMap)
if len(p.Filename) > 0 {
buf, err = ioutil.ReadFile(p.Filename)
if err != nil {
return nil, err
}
} else {
buf, err = autogen.Asset(defaultTemplateFile)
if err != nil {
return nil, err
}
}
_, err = tmpl.Parse(string(buf))
if err != nil {
return nil, err
}
var buffer bytes.Buffer
err = tmpl.Execute(&buffer, templateObjects)
if err != nil {
return nil, err
}
if _, err := toml.Decode(buffer.String(), configuration); err != nil {
return nil, err
}
return configuration, nil
}
func replace(s1 string, s2 string, s3 string) string {
return strings.Replace(s3, s1, s2, -1)
}
// Escape beginning slash "/", convert all others to dash "-"
func getEscapedName(name string) string {
return strings.Replace(strings.TrimPrefix(name, "/"), "/", "-", -1)
}
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), "-")
}
// golang does not support ^ operator
func xor(cond1 bool, cond2 bool) bool {
return cond1 != cond2
}