traefik/types/types.go
Owen Marshall dc52abf4ce
Add sticky session support to Traefik.
This change adds sticky session support, by using the new
oxy/rr/StickySession feature.

To use it, set traefik.backend.sticky to true.

This is currently only implemented in the wrr load balancer, and against
the Marathon backend, but lifting it should be very doable.

In the wrr load balancer, a cookie called _TRAEFIK_SERVERNAME will be
set with the backend to use.  If the cookie is altered to an invalid
backend server, or the server is removed from the load balancer, the
next server will be used instead.

Otherwise, the cookie will be checked in Oxy's rr on access and if valid
the connection will be wired through to it.
2016-09-30 10:56:17 +02:00

212 lines
5.3 KiB
Go

package types
import (
"errors"
"fmt"
"github.com/ryanuber/go-glob"
"strings"
)
// Backend holds backend configuration.
type Backend struct {
Servers map[string]Server `json:"servers,omitempty"`
CircuitBreaker *CircuitBreaker `json:"circuitBreaker,omitempty"`
LoadBalancer *LoadBalancer `json:"loadBalancer,omitempty"`
MaxConn *MaxConn `json:"maxConn,omitempty"`
}
// MaxConn holds maximum connection configuration
type MaxConn struct {
Amount int64 `json:"amount,omitempty"`
ExtractorFunc string `json:"extractorFunc,omitempty"`
}
// LoadBalancer holds load balancing configuration.
type LoadBalancer struct {
Method string `json:"method,omitempty"`
Sticky bool `json:"sticky,omitempty"`
}
// CircuitBreaker holds circuit breaker configuration.
type CircuitBreaker struct {
Expression string `json:"expression,omitempty"`
}
// Server holds server configuration.
type Server struct {
URL string `json:"url,omitempty"`
Weight int `json:"weight"`
}
// Route holds route configuration.
type Route struct {
Rule string `json:"rule,omitempty"`
}
// Frontend holds frontend configuration.
type Frontend struct {
EntryPoints []string `json:"entryPoints,omitempty"`
Backend string `json:"backend,omitempty"`
Routes map[string]Route `json:"routes,omitempty"`
PassHostHeader bool `json:"passHostHeader,omitempty"`
Priority int `json:"priority"`
}
// LoadBalancerMethod holds the method of load balancing to use.
type LoadBalancerMethod uint8
const (
// Wrr (default) = Weighted Round Robin
Wrr LoadBalancerMethod = iota
// Drr = Dynamic Round Robin
Drr
)
var loadBalancerMethodNames = []string{
"Wrr",
"Drr",
}
// NewLoadBalancerMethod create a new LoadBalancerMethod from a given LoadBalancer.
func NewLoadBalancerMethod(loadBalancer *LoadBalancer) (LoadBalancerMethod, error) {
if loadBalancer != nil {
for i, name := range loadBalancerMethodNames {
if strings.EqualFold(name, loadBalancer.Method) {
return LoadBalancerMethod(i), nil
}
}
}
return Wrr, ErrInvalidLoadBalancerMethod
}
// ErrInvalidLoadBalancerMethod is thrown when the specified load balancing method is invalid.
var ErrInvalidLoadBalancerMethod = errors.New("Invalid method, using default")
// Configuration of a provider.
type Configuration struct {
Backends map[string]*Backend `json:"backends,omitempty"`
Frontends map[string]*Frontend `json:"frontends,omitempty"`
}
// ConfigMessage hold configuration information exchanged between parts of traefik.
type ConfigMessage struct {
ProviderName string
Configuration *Configuration
}
// Constraint hold a parsed constraint expresssion
type Constraint struct {
Key string
// MustMatch is true if operator is "==" or false if operator is "!="
MustMatch bool
// TODO: support regex
Regex string
}
// NewConstraint receive a string and return a *Constraint, after checking syntax and parsing the constraint expression
func NewConstraint(exp string) (*Constraint, error) {
sep := ""
constraint := &Constraint{}
if strings.Contains(exp, "==") {
sep = "=="
constraint.MustMatch = true
} else if strings.Contains(exp, "!=") {
sep = "!="
constraint.MustMatch = false
} else {
return nil, errors.New("Constraint expression missing valid operator: '==' or '!='")
}
kv := strings.SplitN(exp, sep, 2)
if len(kv) == 2 {
// At the moment, it only supports tags
if kv[0] != "tag" {
return nil, errors.New("Constraint must be tag-based. Syntax: tag==us-*")
}
constraint.Key = kv[0]
constraint.Regex = kv[1]
return constraint, nil
}
return nil, errors.New("Incorrect constraint expression: " + exp)
}
func (c *Constraint) String() string {
if c.MustMatch {
return c.Key + "==" + c.Regex
}
return c.Key + "!=" + c.Regex
}
// UnmarshalText define how unmarshal in TOML parsing
func (c *Constraint) UnmarshalText(text []byte) error {
constraint, err := NewConstraint(string(text))
*c = *constraint
return err
}
// MatchConstraintWithAtLeastOneTag tests a constraint for one single service
func (c *Constraint) MatchConstraintWithAtLeastOneTag(tags []string) bool {
for _, tag := range tags {
if glob.Glob(c.Regex, tag) {
return true
}
}
return false
}
//Set []*Constraint
func (cs *Constraints) Set(str string) error {
exps := strings.Split(str, ",")
if len(exps) == 0 {
return errors.New("Bad Constraint format: " + str)
}
for _, exp := range exps {
constraint, err := NewConstraint(exp)
if err != nil {
return err
}
*cs = append(*cs, *constraint)
}
return nil
}
// Constraints holds a Constraint parser
type Constraints []Constraint
//Get []*Constraint
func (cs *Constraints) Get() interface{} { return []Constraint(*cs) }
//String returns []*Constraint in string
func (cs *Constraints) String() string { return fmt.Sprintf("%+v", *cs) }
//SetValue sets []*Constraint into the parser
func (cs *Constraints) SetValue(val interface{}) {
*cs = Constraints(val.(Constraints))
}
// Type exports the Constraints type as a string
func (cs *Constraints) Type() string {
return fmt.Sprint("constraint")
}
// Auth holds authentication configuration (BASIC, DIGEST, users)
type Auth struct {
Basic *Basic
Digest *Digest
}
// Users authentication users
type Users []string
// Basic HTTP basic authentication
type Basic struct {
Users
}
// Digest HTTP authentication
type Digest struct {
Users
}