README
¶
Simple Service registry based on pub/sub pattern
This first version service registry use nats (https://nats.io/) to implement a service registry You just need to start nats before using this service registry
The project is still under development and is not ready for production.
Simple to use:
API is simple to use, simple to understand. No required external installation. No configuration file is required.
- Connect:
registry.Connect(registry.Nats(c))init the service both on the client/server side and return registry service instance. - Register:
reg.Register(registry.Service{Name: "httptest", URL: "http://localhost:8083/test"})register you service on the service side. - GetService:
reg.GetService("myservice")on the client side - Unregister:
reg.Unregister("myservice")on the service side - Close :
reg.Close()on the server side 'Close' function deregisters all registered services. On the client and service side, unsubsribe to subscriptions
Safe
Can be used in concurrent context. Singleton design pattern is used.
The first called to registry.Connect(registry.Nats(c), registry.Timeout(100*time.MilliSecond)) create instance of registry service.
And then you can get an instance of registry service without argument reg, _ := registry.Connect()
Fast
This "service registry" uses a local cache as well as the pub / sub pattern. The registration of a new service is in real time. When a new service registers, all clients are notified in real time and update their cache.
Light
The project uses very few external dependencies. There is no service to install. Just your favorite pub/sub implementation (NATS)
Multi-tenant
Multi-tenant support is planned. The tool is based on pub / sub, each message can be pre-fixed by a text of your choice.
Exemple
on the server side :
//connect to nats server
c, err := nats.Connect("localhost:4222")
if err != nil {
log.Fatal("Could not connect to nats: ", err)
}
//Create registry instance
reg, err := registry.Connect(registry.Nats(c))
if err != nil {
log.Fatal("Could not open registry session", err)
}
//Register
unregister, err := reg.Register(registry.Service{Name: "httptest", URL: "http://localhost:8083/test"})
if err != nil {
log.Fatal("Could not register the service ", err)
}
//call the unregister func when the service is shuting done
defer unregister()
// Start your service ...
On the client side :
//connect to nats server
c, err := nats.Connect("localhost:4222")
if err != nil {
log.Fatal("Could not connect to nats: ", err)
}
//Create registry instance
reg, err := registry.Connect(registry.Nats(c))
if err != nil {
log.Fatal("Could not open registry session", err)
}
//registry service register to nats all event for the service httptest
//This is optional, registry
err = registry.Observe("httptest")
if err != nil {
log.Error("Could not observe service ", err)
return
}
services, err := r.GetServices( "httptest")
if err != nil {
log.Error("Could not get services ", err)
return
}
//Do something with services
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( //DefaultTimeout timeout for GetServices DefaultTimeout = 100 * time.Millisecond //DefaultRegisterInterval time between 2 registration DefaultRegisterInterval = 20 * time.Second //DefaultCheckDueInterval time between 2 checks DefaultCheckDueInterval = 200 * time.Millisecond //DefaultMainTopic default message base. All topics will start with this message DefaultMainTopic string //DefaultDueDurationFactor service expire when currentTime > lastRegisteredTime + registerInternal * dueDrationFactor DefaultDueDurationFactor = float32(1.5) )
var ( //ErrNotFound when no service found ErrNotFound = errors.New("No service found") )
Functions ¶
Types ¶
type Filter ¶
Filter used for filtering service do not return nil
func LocalhostFilter ¶
func LocalhostFilter() Filter
LocalhostFilter return true if hostname is equals to service host
type Option ¶
type Option func(opts *Options)
Option option func
func RegisterInterval ¶
RegisterInterval time between 2 register publish
type Options ¶
type Options struct {
// contains filtered or unexported fields
}
Options all configurable option
type Pong ¶
type Pong struct {
Service
Timestamps *Timestamps `json:"t,omitempty"`
}
Pong response to ping
type Registry ¶
type Registry interface {
Register(s Service) (FnUnregister, error)
GetServices(name string) ([]Service, error)
GetService(name string, filters ...Filter) (*Service, error)
Observe(serviceName string) error
Close() error
}
Registry Register, Unregister
type Service ¶
type Service struct {
//Network tcp/unix/tpc6
Network string `json:"net,omitempty"`
//Bind address
Address string `json:"add,omitempty"`
//URL base used for communicate with this service
URL string `json:"url,omitempty"`
//Name service name
Name string `json:"name,omitempty"`
//Version semver version
Version string `json:"v,omitempty"`
//Host
Host string `json:"h,omitempty"`
// contains filtered or unexported fields
}
Service service struct
type Timestamps ¶
type Timestamps struct {
//date registered in nanoseconds (unix timestamp)
Registered int64
//expiration duration in milliseconds
Duration int
}
Timestamps define registered datetime and expiration duration
Source Files
Directories