$ docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
47b494323296 consul "docker-entrypoint.s…" 11 seconds ago Up 9 seconds 8300-8302/tcp, 8500/tcp, 8301-8302/udp, 8600/tcp, 8600/udp, 0.0.0.0:8500->8500/tcp dev-consul
$ docker run -d --name=dev-consul1 -e CONSUL_BIND_INTERFACE=eth0 consul agent -dev -join=172.17.0.2
$ docker run -d --name=dev-consul2 -e CONSUL_BIND_INTERFACE=eth0 consul agent -dev -join=172.17.0.2
$ docker exec -t dev-consul consul members
Node Address Status Type Build Protocol DC Segment
3a993c913dfa 172.17.0.3:8301 alive server 1.5.1 2 dc1 <all>
47b494323296 172.17.0.2:8301 alive server 1.5.1 2 dc1 <all>
7bc5b37a4e1a 172.17.0.4:8301 alive server 1.5.1 2 dc1 <all>
docker run -d --name=dev-consul-agent -e CONSUL_CLIENT_INTERFACE=eth0 consul agent -retry-join=172.17.0.2
$ docker logs 7509e2b8a31a
==> Found address '172.17.0.5' for interface 'eth0', setting client option...
==> Starting Consul agent...
==> Consul agent running!
Version: 'v1.5.1'
Node ID: 'a10e290d-9d1f-69a0-dc19-58c08fe7eaf3'
Node name: '7509e2b8a31a'
Datacenter: 'dc1' (Segment: '')
Server: false (Bootstrap: false)
Client Addr: [172.17.0.5] (HTTP: 8500, HTTPS: -1, gRPC: -1, DNS: 8600)
Cluster Addr: 172.17.0.5 (LAN: 8301, WAN: 8302)
Encrypt: Gossip: false, TLS-Outgoing: false, TLS-Incoming: false
==> Log data will now stream in as it occurs:
2019/06/18 07:58:00 [INFO] serf: EventMemberJoin: 7509e2b8a31a 172.17.0.5
2019/06/18 07:58:00 [INFO] agent: Started DNS server 172.17.0.5:8600 (udp)
2019/06/18 07:58:00 [INFO] agent: Started DNS server 172.17.0.5:8600 (tcp)
2019/06/18 07:58:00 [INFO] agent: Started HTTP server on 172.17.0.5:8500 (tcp)
2019/06/18 07:58:00 [INFO] agent: started state syncer
2019/06/18 07:58:00 [INFO] serf: EventMemberJoin: 47b494323296 172.17.0.2
2019/06/18 07:58:00 [INFO] agent: Retry join LAN is supported for: aliyun aws azure digitalocean gce k8s mdns os packet scaleway softlayer triton vsphere
2019/06/18 07:58:00 [INFO] consul: adding server 47b494323296 (Addr: tcp/172.17.0.2:8300) (DC: dc1)
2019/06/18 07:58:00 [INFO] agent: Joining LAN cluster...
2019/06/18 07:58:00 [INFO] agent: (LAN) joining: [172.17.0.2]
2019/06/18 07:58:00 [WARN] manager: No servers available
2019/06/18 07:58:00 [ERR] agent: failed to sync remote state: No known Consul servers
2019/06/18 07:58:00 [INFO] serf: EventMemberJoin: 3a993c913dfa 172.17.0.3
2019/06/18 07:58:00 [INFO] serf: EventMemberJoin: 7bc5b37a4e1a 172.17.0.4
2019/06/18 07:58:00 [INFO] consul: adding server 3a993c913dfa (Addr: tcp/172.17.0.3:8300) (DC: dc1)
2019/06/18 07:58:00 [INFO] consul: adding server 7bc5b37a4e1a (Addr: tcp/172.17.0.4:8300) (DC: dc1)
2019/06/18 07:58:00 [INFO] agent: (LAN) joined: 1 Err: <nil>
2019/06/18 07:58:00 [INFO] agent: Join LAN completed. Synced with 1 initial agents
2019/06/18 07:58:00 [INFO] agent: Synced node info
$ docker exec -t dev-consul consul members
Node Address Status Type Build Protocol DC Segment
3a993c913dfa 172.17.0.3:8301 alive server 1.5.1 2 dc1 <all>
47b494323296 172.17.0.2:8301 alive server 1.5.1 2 dc1 <all>
7bc5b37a4e1a 172.17.0.4:8301 alive server 1.5.1 2 dc1 <all>
7509e2b8a31a 172.17.0.5:8301 alive client 1.5.1 2 dc1 <default>
// ConsulService 根据自己的需求进行的服务定制
type ConsulService struct {
IP string
Port int
Tag []string
Name string
}
//RegisterService 向consul中注册服务
func RegisterService(consulAddress string, service *ConsulService) {
consulConfig := api.DefaultConfig()
consulConfig.Address = consulAddress
client, err := api.NewClient(consulConfig)
if err != nil {
log.Errorf("New consul client err \n: %v", err)
return
}
agent := client.Agent()
interval := time.Duration(10) * time.Second
deregister := time.Duration(1) * time.Minute
reg := &api.AgentServiceRegistration{
ID: fmt.Sprintf("%v-%v-%v", service.Name, service.IP, service.Port), // 服务节点的名称
Name: service.Name, // 服务名称
Tags: service.Tag, // tag，可以为空
Port: service.Port, // 服务端口
Address: service.IP, // 服务 IP
// In Consul 0.7 and later, checks that are associated with a service
// may also contain this optional DeregisterCriticalServiceAfter field,
// which is a timeout in the same Go time format as Interval and TTL. If
// a check is in the critical state for more than this configured value,
// then its associated service (and all of its associated checks) will
// automatically be deregistered.
Check: &api.AgentServiceCheck{ // 健康检查
Interval: interval.String(), // 健康检查间隔
GRPC: fmt.Sprintf("%v:%v/%v", service.IP, service.Port, service.Name), // grpc 支持，执行健康检查的地址，service 会传到 Health.Check 函数中
DeregisterCriticalServiceAfter: deregister.String(), // 注销时间，相当于过期时间
},
}
log.Printf("registing to %v\n", consulAddress)
if err := agent.ServiceRegister(reg); err != nil {
log.Printf("Service Register error\n%v", err)
return
}
}
package consul
import (
"errors"
"fmt"
"regexp"
"sync"
"google.golang.org/grpc/serviceconfig"
"github.com/hashicorp/consul/api"
log "github.com/sirupsen/logrus"
"google.golang.org/grpc/resolver"
)
const (
defaultPort = "8500"
)
var (
errMissingAddr = errors.New("consul resolver: missing address")
errAddrMisMatch = errors.New("consul resolver: invalied uri")
errEndsWithColon = errors.New("consul resolver: missing port after port-separator colon")
regexConsul, _ = regexp.Compile("^([A-z0-9.]+)(:[0-9]{1,5})?/([A-z_]+)$")
)
// Init consul resolver
func Init() {
log.Printf("calling consul init\n")
resolver.Register(NewBuilder())
}
type consulBuilder struct {
}
type consulResolver struct {
address string
wg sync.WaitGroup
clientConn resolver.ClientConn
name string
disableServiceConfig bool
lastIndex uint64
}
// NewBuilder new consulBuilder
func NewBuilder() resolver.Builder {
return &consulBuilder{}
}
func (cb *consulBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOption) (resolver.Resolver, error) {
log.Printf("calling consul build\n")
log.Printf("target: %v\n", target)
host, port, name, err := parseTarget(fmt.Sprintf("%s/%s", target.Authority, target.Endpoint))
if err != nil {
return nil, err
}
cr := &consulResolver{
address: fmt.Sprintf("%s%s", host, port),
name: name,
clientConn: cc,
disableServiceConfig: opts.DisableServiceConfig,
lastIndex: 0,
}
cr.wg.Add(1)
go cr.watcher()
return cr, nil
}
func (cr *consulResolver) watcher() {
log.Printf("calling consul watcher\n")
config := api.DefaultConfig()
config.Address = cr.address
client, err := api.NewClient(config)
if err != nil {
log.Printf("error create consul client: %v\n", err)
return
}
for {
services, metainfo, err := client.Health().Service(cr.name, cr.name, true, &api.QueryOptions{WaitIndex: cr.lastIndex})
if err != nil {
log.Printf("error retrieving instances from Consul: %v", err)
}
cr.lastIndex = metainfo.LastIndex
var newAddrs []resolver.Address
for _, service := range services {
addr := fmt.Sprintf("%v:%v", service.Service.Address, service.Service.Port)
newAddrs = append(newAddrs, resolver.Address{Addr: addr})
}
log.Printf("adding service addrs\n")
log.Printf("newAddrs: %v\n", newAddrs)
serviceConfig, err := serviceconfig.Parse(cr.name)
if err != nil {
state := resolver.State{
Addresses: newAddrs,
ServiceConfig: serviceConfig,
}
cr.clientConn.UpdateState(state)
} else {
log.Error(err.Error())
}
}
}
func (cb *consulBuilder) Scheme() string {
return "consul"
}
func (cr *consulResolver) ResolveNow(opt resolver.ResolveNowOption) {
}
func (cr *consulResolver) Close() {
}
func parseTarget(target string) (host, port, name string, err error) {
log.Printf("target uri: %v\n", target)
if target == "" {
return "", "", "", errMissingAddr
}
if !regexConsul.MatchString(target) {
return "", "", "", errAddrMisMatch
}
groups := regexConsul.FindStringSubmatch(target)
host = groups[1]
port = groups[2]
name = groups[3]
if port == "" {
port = defaultPort
}
return host, port, name, nil
}
$ go run server/cmd/main.go
INFO[0000] registing to 192.168.53.205:8500
INFO[0006] health checking
INFO[0016] health checking
INFO[0026] health checking
INFO[0036] health checking
$ go run client/cmd/main.go
INFO[0000] calling consul init
INFO[0000] calling consul build
INFO[0000] target: {consul 192.168.53.205:8500 helloworld}
INFO[0000] target uri: 192.168.53.205:8500/helloworld
INFO[0000] calling consul watcher
INFO[0000] adding service addrs
INFO[0000] newAddrs: [{192.168.53.205:50051 0 <nil>}]
2019/06/19 14:26:49 Greeting: Hello world
