micro/registry/memory/memory.go

186 lines
3.8 KiB
Go

// Package memory provides an in-memory registry
package memory
import (
"context"
"sync"
"time"
"github.com/google/uuid"
"github.com/micro/go-micro/registry"
)
var (
timeout = time.Millisecond * 10
)
type Registry struct {
options registry.Options
sync.RWMutex
Services map[string][]*registry.Service
Watchers map[string]*Watcher
}
func NewRegistry(opts ...registry.Option) registry.Registry {
options := registry.Options{
Context: context.Background(),
}
for _, o := range opts {
o(&options)
}
services := getServices(options.Context)
if services == nil {
services = make(map[string][]*registry.Service)
}
return &Registry{
options: options,
Services: services,
Watchers: make(map[string]*Watcher),
}
}
func (m *Registry) sendEvent(r *registry.Result) {
var watchers []*Watcher
m.RLock()
for _, w := range m.Watchers {
watchers = append(watchers, w)
}
m.RUnlock()
for _, w := range watchers {
select {
case <-w.exit:
m.Lock()
delete(m.Watchers, w.id)
m.Unlock()
default:
select {
case w.res <- r:
case <-time.After(timeout):
}
}
}
}
func (m *Registry) Init(opts ...registry.Option) error {
for _, o := range opts {
o(&m.options)
}
// add services
m.Lock()
for k, v := range getServices(m.options.Context) {
s := m.Services[k]
m.Services[k] = registry.Merge(s, v)
}
m.Unlock()
return nil
}
func (m *Registry) Options() registry.Options {
return m.options
}
func (m *Registry) GetService(name string) ([]*registry.Service, error) {
m.RLock()
service, ok := m.Services[name]
m.RUnlock()
if !ok {
return nil, registry.ErrNotFound
}
return service, nil
}
func (m *Registry) ListServices() ([]*registry.Service, error) {
var services []*registry.Service
m.RLock()
for _, service := range m.Services {
services = append(services, service...)
}
m.RUnlock()
return services, nil
}
func (m *Registry) Register(s *registry.Service, opts ...registry.RegisterOption) error {
m.Lock()
defer m.Unlock()
if service, ok := m.Services[s.Name]; !ok {
m.Services[s.Name] = []*registry.Service{s}
go m.sendEvent(&registry.Result{Action: "update", Service: s})
} else {
svcCount := len(service)
svcNodeCounts := make(map[string]map[string]int)
for _, s := range service {
if _, ok := svcNodeCounts[s.Name]; !ok {
svcNodeCounts[s.Name] = make(map[string]int)
}
if _, ok := svcNodeCounts[s.Name][s.Version]; !ok {
svcNodeCounts[s.Name][s.Version] = len(s.Nodes)
}
}
// if merged count and original service counts changed we added new version of the service
merged := registry.Merge(service, []*registry.Service{s})
if len(merged) != svcCount {
m.Services[s.Name] = merged
go m.sendEvent(&registry.Result{Action: "update", Service: s})
return nil
}
// if the node count for a particular service has changed we added a new node to the service
for _, s := range merged {
if len(s.Nodes) != svcNodeCounts[s.Name][s.Version] {
m.Services[s.Name] = merged
go m.sendEvent(&registry.Result{Action: "update", Service: s})
return nil
}
}
}
return nil
}
func (m *Registry) Deregister(s *registry.Service) error {
m.Lock()
defer m.Unlock()
if service, ok := m.Services[s.Name]; ok {
go m.sendEvent(&registry.Result{Action: "delete", Service: s})
if service := registry.Remove(service, []*registry.Service{s}); len(service) == 0 {
delete(m.Services, s.Name)
} else {
m.Services[s.Name] = service
}
}
return nil
}
func (m *Registry) Watch(opts ...registry.WatchOption) (registry.Watcher, error) {
var wo registry.WatchOptions
for _, o := range opts {
o(&wo)
}
w := &Watcher{
exit: make(chan bool),
res: make(chan *registry.Result),
id: uuid.New().String(),
wo: wo,
}
m.Lock()
m.Watchers[w.id] = w
m.Unlock()
return w, nil
}
func (m *Registry) String() string {
return "memory"
}