micro/service.go
2020-05-13 16:49:17 +01:00

267 lines
6.2 KiB
Go

package micro
import (
"fmt"
"os"
"os/signal"
rtime "runtime"
"strings"
"sync"
"github.com/micro/go-micro/v2/auth"
"github.com/micro/go-micro/v2/client"
"github.com/micro/go-micro/v2/config/cmd"
"github.com/micro/go-micro/v2/debug/service/handler"
"github.com/micro/go-micro/v2/debug/stats"
"github.com/micro/go-micro/v2/debug/trace"
"github.com/micro/go-micro/v2/logger"
"github.com/micro/go-micro/v2/plugin"
registrySrv "github.com/micro/go-micro/v2/registry/service"
"github.com/micro/go-micro/v2/runtime"
"github.com/micro/go-micro/v2/server"
"github.com/micro/go-micro/v2/store"
signalutil "github.com/micro/go-micro/v2/util/signal"
"github.com/micro/go-micro/v2/util/wrapper"
)
type service struct {
opts Options
once sync.Once
}
func newService(opts ...Option) Service {
service := new(service)
options := newOptions(opts...)
// service name
serviceName := options.Server.Options().Name
// authFn returns the auth, we pass as a function since auth
// has not yet been set at this point.
authFn := func() auth.Auth { return options.Server.Options().Auth }
// wrap client to inject From-Service header on any calls
options.Client = wrapper.FromService(serviceName, options.Client)
options.Client = wrapper.TraceCall(serviceName, trace.DefaultTracer, options.Client)
options.Client = wrapper.AuthClient(serviceName, options.Server.Options().Id, authFn, options.Client)
// wrap the server to provide handler stats
options.Server.Init(
server.WrapHandler(wrapper.HandlerStats(stats.DefaultStats)),
server.WrapHandler(wrapper.TraceHandler(trace.DefaultTracer)),
server.WrapHandler(wrapper.AuthHandler(authFn)),
)
// set the client in the service implementations
options.Auth.Init(auth.WithClient(options.Client))
options.Registry.Init(registrySrv.WithClient(options.Client))
options.Runtime.Init(runtime.WithClient(options.Client))
options.Store.Init(store.WithClient(options.Client))
// set opts
service.opts = options
return service
}
func (s *service) Name() string {
return s.opts.Server.Options().Name
}
// Init initialises options. Additionally it calls cmd.Init
// which parses command line flags. cmd.Init is only called
// on first Init.
func (s *service) Init(opts ...Option) {
// process options
for _, o := range opts {
o(&s.opts)
}
s.once.Do(func() {
// setup the plugins
for _, p := range strings.Split(os.Getenv("MICRO_PLUGIN"), ",") {
if len(p) == 0 {
continue
}
// load the plugin
c, err := plugin.Load(p)
if err != nil {
logger.Fatal(err)
}
// initialise the plugin
if err := plugin.Init(c); err != nil {
logger.Fatal(err)
}
}
// set cmd name
if len(s.opts.Cmd.App().Name) == 0 {
s.opts.Cmd.App().Name = s.Server().Options().Name
}
// Initialise the command flags, overriding new service
if err := s.opts.Cmd.Init(
cmd.Auth(&s.opts.Auth),
cmd.Broker(&s.opts.Broker),
cmd.Registry(&s.opts.Registry),
cmd.Runtime(&s.opts.Runtime),
cmd.Transport(&s.opts.Transport),
cmd.Client(&s.opts.Client),
cmd.Config(&s.opts.Config),
cmd.Server(&s.opts.Server),
cmd.Store(&s.opts.Store),
cmd.Profile(&s.opts.Profile),
); err != nil {
logger.Fatal(err)
}
// Explicitly set the table name to the service name
name := s.opts.Cmd.App().Name
s.opts.Store.Init(store.Table(name))
// Reset the clients for the micro services, this is done
// previously in newService for micro (since init is never called)
// however it needs to be done again here since for normal go-micro
// services the implementation may have changed by CLI flags.
s.opts.Auth.Init(auth.WithClient(s.Client()))
s.opts.Registry.Init(registrySrv.WithClient(s.Client()))
s.opts.Runtime.Init(runtime.WithClient(s.Client()))
s.opts.Store.Init(store.WithClient(s.Client()))
})
}
func (s *service) Options() Options {
return s.opts
}
func (s *service) Client() client.Client {
return s.opts.Client
}
func (s *service) Server() server.Server {
return s.opts.Server
}
func (s *service) String() string {
return "micro"
}
func (s *service) Start() error {
for _, fn := range s.opts.BeforeStart {
if err := fn(); err != nil {
return err
}
}
if err := s.opts.Server.Start(); err != nil {
return err
}
for _, fn := range s.opts.AfterStart {
if err := fn(); err != nil {
return err
}
}
return nil
}
func (s *service) Stop() error {
var gerr error
for _, fn := range s.opts.BeforeStop {
if err := fn(); err != nil {
gerr = err
}
}
if err := s.opts.Server.Stop(); err != nil {
return err
}
for _, fn := range s.opts.AfterStop {
if err := fn(); err != nil {
gerr = err
}
}
return gerr
}
func (s *service) Run() error {
// generate an auth account
if err := s.generateAccount(); err != nil {
return err
}
// register the debug handler
s.opts.Server.Handle(
s.opts.Server.NewHandler(
handler.NewHandler(),
server.InternalHandler(true),
),
)
// start the profiler
if s.opts.Profile != nil {
// to view mutex contention
rtime.SetMutexProfileFraction(5)
// to view blocking profile
rtime.SetBlockProfileRate(1)
if err := s.opts.Profile.Start(); err != nil {
return err
}
defer s.opts.Profile.Stop()
}
if logger.V(logger.InfoLevel, logger.DefaultLogger) {
logger.Infof("Starting [service] %s", s.Name())
}
if err := s.Start(); err != nil {
return err
}
ch := make(chan os.Signal, 1)
if s.opts.Signal {
signal.Notify(ch, signalutil.Shutdown()...)
}
select {
// wait on kill signal
case <-ch:
// wait on context cancel
case <-s.opts.Context.Done():
}
return s.Stop()
}
func (s *service) generateAccount() error {
// generate a new auth account for the service
name := fmt.Sprintf("%v-%v", s.Name(), s.Server().Options().Id)
opts := []auth.GenerateOption{
auth.WithType("service"),
auth.WithRoles("service"),
auth.WithNamespace(s.Options().Auth.Options().Namespace),
}
acc, err := s.Options().Auth.Generate(name, opts...)
if err != nil {
return err
}
// generate a token
token, err := s.Options().Auth.Token(auth.WithCredentials(acc.ID, acc.Secret))
if err != nil {
return err
}
s.Options().Auth.Init(auth.ClientToken(token), auth.Credentials(acc.ID, acc.Secret))
logger.Infof("Auth [%v] Authenticated as %v", s.Options().Auth, name)
return nil
}