micro/registry/consul_registry.go
2016-01-26 20:44:29 +00:00

283 lines
5.5 KiB
Go

package registry
import (
"crypto/tls"
"encoding/json"
"errors"
"fmt"
"net"
"net/http"
"runtime"
"time"
consul "github.com/hashicorp/consul/api"
)
type consulRegistry struct {
Address string
Client *consul.Client
Options Options
}
func newTransport(config *tls.Config) *http.Transport {
if config == nil {
config = &tls.Config{
InsecureSkipVerify: true,
}
}
t := &http.Transport{
Proxy: http.ProxyFromEnvironment,
Dial: (&net.Dialer{
Timeout: 30 * time.Second,
KeepAlive: 30 * time.Second,
}).Dial,
TLSHandshakeTimeout: 10 * time.Second,
TLSClientConfig: config,
}
runtime.SetFinalizer(&t, func(tr **http.Transport) {
(*tr).CloseIdleConnections()
})
return t
}
func encodeEndpoints(en []*Endpoint) []string {
var tags []string
for _, e := range en {
if b, err := json.Marshal(e); err == nil {
tags = append(tags, "e="+string(b))
}
}
return tags
}
func decodeEndpoints(tags []string) []*Endpoint {
var en []*Endpoint
for _, tag := range tags {
if len(tag) == 0 || tag[0] != 'e' {
continue
}
var e *Endpoint
if err := json.Unmarshal([]byte(tag[2:]), &e); err == nil {
en = append(en, e)
}
}
return en
}
func encodeMetadata(md map[string]string) []string {
var tags []string
for k, v := range md {
if b, err := json.Marshal(map[string]string{
k: v,
}); err == nil {
tags = append(tags, "t="+string(b))
}
}
return tags
}
func decodeMetadata(tags []string) map[string]string {
md := make(map[string]string)
for _, tag := range tags {
if len(tag) == 0 || tag[0] != 't' {
continue
}
var kv map[string]string
if err := json.Unmarshal([]byte(tag[2:]), &kv); err == nil {
for k, v := range kv {
md[k] = v
}
}
}
return md
}
func encodeVersion(v string) string {
return "v=" + v
}
func decodeVersion(tags []string) (string, bool) {
for _, tag := range tags {
if len(tag) == 0 || tag[0] != 'v' {
continue
}
return tag[2:], true
}
return "", false
}
func newConsulRegistry(addrs []string, opts ...Option) Registry {
var opt Options
for _, o := range opts {
o(&opt)
}
// use default config
config := consul.DefaultConfig()
// set timeout
if opt.Timeout > 0 {
config.HttpClient.Timeout = opt.Timeout
}
// check if there are any addrs
if len(addrs) > 0 {
addr, port, err := net.SplitHostPort(addrs[0])
if ae, ok := err.(*net.AddrError); ok && ae.Err == "missing port in address" {
port = "8500"
addr = addrs[0]
config.Address = fmt.Sprintf("%s:%s", addr, port)
} else if err == nil {
config.Address = fmt.Sprintf("%s:%s", addr, port)
}
}
// requires secure connection?
if opt.Secure || opt.TLSConfig != nil {
config.Scheme = "https"
// We're going to support InsecureSkipVerify
config.HttpClient.Transport = newTransport(opt.TLSConfig)
}
// create the client
client, _ := consul.NewClient(config)
cr := &consulRegistry{
Address: config.Address,
Client: client,
Options: opt,
}
return cr
}
func (c *consulRegistry) Deregister(s *Service) error {
if len(s.Nodes) == 0 {
return errors.New("Require at least one node")
}
node := s.Nodes[0]
_, err := c.Client.Catalog().Deregister(&consul.CatalogDeregistration{
Node: node.Id,
Address: node.Address,
ServiceID: node.Id,
}, nil)
return err
}
func (c *consulRegistry) Register(s *Service) error {
if len(s.Nodes) == 0 {
return errors.New("Require at least one node")
}
node := s.Nodes[0]
tags := encodeMetadata(node.Metadata)
tags = append(tags, encodeEndpoints(s.Endpoints)...)
tags = append(tags, encodeVersion(s.Version))
if _, err := c.Client.Catalog().Register(&consul.CatalogRegistration{
// TODO: remove setting node and address
Node: node.Id,
Address: node.Address,
Service: &consul.AgentService{
ID: node.Id,
Service: s.Name,
Port: node.Port,
Tags: tags,
Address: node.Address,
},
}, nil); err != nil {
return err
}
return nil
}
func (c *consulRegistry) GetService(name string) ([]*Service, error) {
rsp, _, err := c.Client.Catalog().Service(name, "", nil)
if err != nil {
return nil, err
}
serviceMap := map[string]*Service{}
for _, s := range rsp {
if s.ServiceName != name {
continue
}
// version is now a tag
version, found := decodeVersion(s.ServiceTags)
// service ID is now the node id
id := s.ServiceID
// key is always the version
key := version
// address is service address
address := s.ServiceAddress
// if we can't get the new type of version
// use old the old ways
if !found {
// id was set as node
id = s.Node
// key was service id
key = s.ServiceID
// version was service id
version = s.ServiceID
// address was address
address = s.Address
}
svc, ok := serviceMap[key]
if !ok {
svc = &Service{
Endpoints: decodeEndpoints(s.ServiceTags),
Name: s.ServiceName,
Version: version,
}
serviceMap[key] = svc
}
svc.Nodes = append(svc.Nodes, &Node{
Id: id,
Address: address,
Port: s.ServicePort,
Metadata: decodeMetadata(s.ServiceTags),
})
}
var services []*Service
for _, service := range serviceMap {
services = append(services, service)
}
return services, nil
}
func (c *consulRegistry) ListServices() ([]*Service, error) {
rsp, _, err := c.Client.Catalog().Services(nil)
if err != nil {
return nil, err
}
var services []*Service
for service, _ := range rsp {
services = append(services, &Service{Name: service})
}
return services, nil
}
func (c *consulRegistry) Watch() (Watcher, error) {
return newConsulWatcher(c)
}
func (c *consulRegistry) String() string {
return "consul"
}