Merge branch 'master' of ssh://github.com/micro/go-micro

This commit is contained in:
Asim Aslam 2019-07-01 18:37:45 +01:00
commit d3e200575c
7 changed files with 294 additions and 63 deletions

View File

@ -4,6 +4,7 @@ import (
"fmt"
"strings"
"sync"
"time"
"github.com/micro/go-micro/registry"
"github.com/olekukonko/tablewriter"
@ -12,15 +13,15 @@ import (
// router provides default router implementation
type router struct {
opts Options
status Status
advertChan chan *Update
exit chan struct{}
wg *sync.WaitGroup
sync.RWMutex
}
// newRouter creates new router and returns it
func newRouter(opts ...Option) Router {
// TODO: we need to add default GW entry here
// Should default GW be part of router options?
// get default options
options := DefaultOptions()
@ -31,6 +32,8 @@ func newRouter(opts ...Option) Router {
return &router{
opts: options,
status: Status{Error: nil, Code: Init},
advertChan: make(chan *Update),
exit: make(chan struct{}),
wg: &sync.WaitGroup{},
}
@ -69,43 +72,17 @@ func (r *router) Network() string {
return r.opts.Network
}
// Advertise advertises the routes to the network. It is a blocking function.
// It returns error if any of the launched goroutines fail with error.
func (r *router) Advertise() error {
// add local service routes into the routing table
if err := r.addServiceRoutes(r.opts.Registry, "local", DefaultLocalMetric); err != nil {
return fmt.Errorf("failed adding routes: %v", err)
}
localWatcher, err := r.opts.Registry.Watch()
if err != nil {
return fmt.Errorf("failed to create registry watcher: %v", err)
}
// error channel collecting goroutine errors
errChan := make(chan error, 1)
r.wg.Add(1)
go func() {
defer r.wg.Done()
// watch local registry and register routes in routine table
errChan <- r.manageServiceRoutes(localWatcher, DefaultLocalMetric)
}()
return <-errChan
}
// addServiceRoutes adds all services in given registry to the routing table.
// NOTE: this is a one-off operation done when bootstrapping the routing table
// It returns error if either the services failed to be listed or
// if the routes could not be added to the routing table.
// if any of the the routes could not be added to the routing table.
func (r *router) addServiceRoutes(reg registry.Registry, network string, metric int) error {
services, err := reg.ListServices()
if err != nil {
return fmt.Errorf("failed to list services: %v", err)
}
// add each service node as a separate route;
// add each service node as a separate route
for _, service := range services {
// get the service to retrieve all its info
srvs, err := reg.GetService(service.Name)
@ -121,13 +98,13 @@ func (r *router) addServiceRoutes(reg registry.Registry, network string, metric
// range over the flat slice of nodes
for _, node := range nodes {
gw := node.Address
gateway := node.Address
if node.Port > 0 {
gw = fmt.Sprintf("%s:%d", node.Address, node.Port)
gateway = fmt.Sprintf("%s:%d", node.Address, node.Port)
}
route := Route{
Destination: service.Name,
Gateway: gw,
Gateway: gateway,
Router: r.opts.Address,
Network: r.opts.Network,
Metric: metric,
@ -157,12 +134,10 @@ func (r *router) manageServiceRoutes(w registry.Watcher, metric int) error {
for {
res, err := w.Next()
if err == registry.ErrWatcherStopped {
break
}
if err != nil {
if err != registry.ErrWatcherStopped {
watchErr = err
}
break
}
@ -190,10 +165,190 @@ func (r *router) manageServiceRoutes(w registry.Watcher, metric int) error {
return watchErr
}
// watchTable watches routing table entries and either adds or deletes locally registered service to/from network registry
// It returns error if the locally registered services either fails to be added/deleted to/from network registry.
func (r *router) watchTable(w Watcher) error {
// wait in the background for the router to stop
// when the router stops, stop the watcher and exit
r.wg.Add(1)
go func() {
defer r.wg.Done()
<-r.exit
w.Stop()
}()
var watchErr error
exit:
for {
event, err := w.Next()
if err != nil {
if err != ErrWatcherStopped {
watchErr = err
}
break
}
u := &Update{
ID: r.ID(),
Timestamp: time.Now(),
Event: event,
}
select {
case <-r.exit:
break exit
case r.advertChan <- u:
}
}
// close the advertisement channel
close(r.advertChan)
return watchErr
}
// watchError watches router errors
func (r *router) watchError(errChan <-chan error) {
defer r.wg.Done()
var code StatusCode
var err error
select {
case <-r.exit:
code = Stopped
case err = <-errChan:
code = Error
}
r.Lock()
defer r.Unlock()
status := Status{
Code: code,
Error: err,
}
r.status = status
// stop the router if some error happened
if err != nil && code != Stopped {
close(r.exit)
}
}
// Advertise advertises the routes to the network.
// It returns error if any of the launched goroutines fail with error.
func (r *router) Advertise() (<-chan *Update, error) {
r.Lock()
defer r.Unlock()
if r.status.Code != Running {
// add local service routes into the routing table
if err := r.addServiceRoutes(r.opts.Registry, "local", DefaultLocalMetric); err != nil {
return nil, fmt.Errorf("failed adding routes: %v", err)
}
// add default gateway into routing table
if r.opts.Gateway != "" {
// note, the only non-default value is the gateway
route := Route{
Destination: "*",
Gateway: r.opts.Gateway,
Router: "*",
Network: "*",
Metric: DefaultLocalMetric,
}
if err := r.opts.Table.Add(route); err != nil {
return nil, fmt.Errorf("error to add default gateway route: %s", err)
}
}
// NOTE: we only need to recreate the exit/advertChan if the router errored or was stopped
if r.status.Code == Error || r.status.Code == Stopped {
r.exit = make(chan struct{})
r.advertChan = make(chan *Update)
}
// routing table watcher which watches all routes i.e. to every destination
tableWatcher, err := r.opts.Table.Watch(WatchDestination("*"))
if err != nil {
return nil, fmt.Errorf("failed to create routing table watcher: %v", err)
}
// registry watcher
regWatcher, err := r.opts.Registry.Watch()
if err != nil {
return nil, fmt.Errorf("failed to create registry watcher: %v", err)
}
// error channel collecting goroutine errors
errChan := make(chan error, 2)
r.wg.Add(1)
go func() {
defer r.wg.Done()
// watch local registry and register routes in routine table
errChan <- r.manageServiceRoutes(regWatcher, DefaultLocalMetric)
}()
r.wg.Add(1)
go func() {
defer r.wg.Done()
// watch local registry and register routes in routing table
errChan <- r.watchTable(tableWatcher)
}()
r.wg.Add(1)
go r.watchError(errChan)
// mark router as running and set its Error to nil
status := Status{
Code: Running,
Error: nil,
}
r.status = status
}
return r.advertChan, nil
}
// Update updates the routing table using the advertised values
func (r *router) Update(a *Update) error {
// we extract the route from advertisement and update the routing table
route := Route{
Destination: a.Event.Route.Destination,
Gateway: a.Event.Route.Gateway,
Router: a.Event.Route.Router,
Network: a.Event.Route.Network,
Metric: a.Event.Route.Metric,
Policy: AddIfNotExists,
}
return r.opts.Table.Update(route)
}
// Status returns router status
func (r *router) Status() Status {
r.RLock()
defer r.RUnlock()
// make a copy of the status
status := r.status
return status
}
// Stop stops the router
func (r *router) Stop() error {
r.RLock()
// only close the channel if the router is running
if r.status.Code == Running {
// notify all goroutines to finish
close(r.exit)
}
r.RUnlock()
// drain the advertise channel
for range r.advertChan {
}
// wait for all goroutines to finish
r.wg.Wait()
@ -206,13 +361,14 @@ func (r *router) String() string {
sb := &strings.Builder{}
table := tablewriter.NewWriter(sb)
table.SetHeader([]string{"ID", "Address", "Network", "Table"})
table.SetHeader([]string{"ID", "Address", "Network", "Table", "Status"})
data := []string{
r.opts.ID,
r.opts.Address,
r.opts.Network,
fmt.Sprintf("%d", r.opts.Table.Size()),
r.status.Code.String(),
}
table.Append(data)

View File

@ -129,6 +129,12 @@ func (t *table) Update(r Route) error {
// check if the destAddr has ANY routes in the table
if _, ok := t.m[destAddr]; !ok {
if r.Policy == AddIfNotExists {
t.m[destAddr] = make(map[uint64]Route)
t.m[destAddr][sum] = r
go t.sendEvent(&Event{Type: CreateEvent, Route: r})
return nil
}
return ErrRouteNotFound
}
@ -279,7 +285,7 @@ func (t *table) String() string {
// hash hashes the route using router gateway and network address
func (t *table) hash(r Route) uint64 {
t.h.Reset()
t.h.Write([]byte(r.Destination + r.Gateway + r.Router + r.Network))
t.h.Write([]byte(r.Destination + r.Gateway + r.Network))
return t.h.Sum64()
}

View File

@ -8,6 +8,8 @@ import (
var (
// DefaultAddress is default router address
DefaultAddress = ":9093"
// DefaultNetwork is default micro network
DefaultNetwork = "local"
)
// Options are router options
@ -18,6 +20,8 @@ type Options struct {
Address string
// Network is micro network
Network string
// Gateway is micro network gateway
Gateway string
// Registry is the local registry
Registry registry.Registry
// Table is routing table
@ -45,6 +49,13 @@ func Network(n string) Option {
}
}
// Gateway sets network gateway
func Gateway(g string) Option {
return func(o *Options) {
o.Gateway = g
}
}
// RoutingTable sets the routing table
func RoutingTable(t Table) Option {
return func(o *Options) {
@ -61,12 +72,11 @@ func Registry(r registry.Registry) Option {
// DefaultOptions returns router default options
func DefaultOptions() Options {
// NOTE: by default both local and network registies use default registry i.e. mdns
return Options{
ID: uuid.New().String(),
Address: DefaultAddress,
Network: DefaultNetwork,
Registry: registry.DefaultRegistry,
Table: NewTable(),
Network: "local",
}
}

View File

@ -20,6 +20,8 @@ type RoutePolicy int
const (
// OverrideIfExists overrides route if it already exists
OverrideIfExists RoutePolicy = iota
// AddIfNotExist adds the route if it does not exist
AddIfNotExists
// IgnoreIfExists instructs to not modify existing route
IgnoreIfExists
)
@ -28,9 +30,11 @@ const (
func (p RoutePolicy) String() string {
switch p {
case OverrideIfExists:
return "OVERRIDE"
return "OVERRIDE_IF_EXISTS"
case AddIfNotExists:
return "ADD_IF_NOT_EXISTS"
case IgnoreIfExists:
return "IGNORE"
return "IGNORE_IF_EXISTS"
default:
return "UNKNOWN"
}

View File

@ -1,6 +1,13 @@
// Package router provides a network routing control plane
package router
import "time"
var (
// DefaultRouter is default network router
DefaultRouter = NewRouter()
)
// Router is an interface for a routing control plane
type Router interface {
// Init initializes the router with options
@ -15,21 +22,69 @@ type Router interface {
Address() string
// Network returns the network address of the router
Network() string
// Advertise starts advertising the routes to the network
Advertise() error
// Advertise starts advertising routes to the network
Advertise() (<-chan *Update, error)
// Update updates the routing table
Update(*Update) error
// Status returns router status
Status() Status
// Stop stops the router
Stop() error
// String returns debug info
String() string
}
// Update is sent by the router to the network
type Update struct {
// ID is the router ID
ID string
// Timestamp marks the time when update is sent
Timestamp time.Time
// Event defines advertisement even
Event *Event
}
// StatusCode defines router status
type StatusCode int
// Status is router status
type Status struct {
// Error is router error
Error error
// Code defines router status
Code StatusCode
}
const (
// Init means the rotuer has just been initialized
Init StatusCode = iota
// Running means the router is running
Running
// Error means the router has crashed with error
Error
// Stopped means the router has stopped
Stopped
)
// String returns human readable status code
func (sc StatusCode) String() string {
switch sc {
case Init:
return "INITIALIZED"
case Running:
return "RUNNING"
case Error:
return "ERROR"
case Stopped:
return "STOPPED"
default:
return "UNKNOWN"
}
}
// Option used by the router
type Option func(*Options)
var (
DefaultRouter = NewRouter()
)
// NewRouter creates new Router and returns it
func NewRouter(opts ...Option) Router {
return newRouter(opts...)

View File

@ -9,7 +9,7 @@ import (
var (
// ErrWatcherStopped is returned when routing table watcher has been stopped
ErrWatcherStopped = errors.New("routing table watcher stopped")
ErrWatcherStopped = errors.New("watcher stopped")
)
// EventType defines routing table event
@ -81,7 +81,7 @@ type tableWatcher struct {
}
// Next returns the next noticed action taken on table
// TODO: this needs to be thought through properly; we only allow watching particular route destination
// TODO: this needs to be thought through properly; we only allow watching particular route destination for now
func (w *tableWatcher) Next() (*Event, error) {
for {
select {
@ -93,6 +93,7 @@ func (w *tableWatcher) Next() (*Event, error) {
if w.opts.Destination == res.Route.Destination {
return res, nil
}
continue
}
case <-w.done:
return nil, ErrWatcherStopped

View File

@ -1,7 +1,6 @@
package registry
import (
"errors"
"strings"
"github.com/micro/mdns"
@ -63,7 +62,7 @@ func (m *mdnsWatcher) Next() (*Result, error) {
Service: service,
}, nil
case <-m.exit:
return nil, errors.New("watcher stopped")
return nil, ErrWatcherStopped
}
}
}