Merge pull request #25 from micro/selector
Add selector interface and implementation
This commit is contained in:
commit
b4e319ee65
@ -16,6 +16,7 @@ Feature | Package | Built-in Plugin | Description
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Discovery | [Registry](https://godoc.org/github.com/micro/go-micro/registry) | consul | A way of locating services to communicate with
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Client | [Client](https://godoc.org/github.com/micro/go-micro/client) | rpc | Used to make RPC requests to a service
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Codec | [Codec](https://godoc.org/github.com/micro/go-micro/codec) | proto,json | Encoding/Decoding handler for requests
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Selector | [Selector](https://godoc.org/github.com/micro/go-micro/selector) | random | Service node filter and pool
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Server | [Server](https://godoc.org/github.com/micro/go-micro/server) | rpc | Listens and serves RPC requests
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Pub/Sub | [Broker](https://godoc.org/github.com/micro/go-micro/broker) | http | Publish and Subscribe to events
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Transport | [Transport](https://godoc.org/github.com/micro/go-micro/transport) | http | Communication mechanism between services
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@ -1,9 +0,0 @@
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package client
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import (
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"github.com/micro/go-micro/registry"
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)
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// Selector takes a Registry and returns a NodeSelector.
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// Used by the client to initialise a selector.
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type Selector func(registry.Registry) NodeSelector
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@ -1,60 +0,0 @@
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package client
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import (
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"math/rand"
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"time"
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"github.com/micro/go-micro/errors"
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"github.com/micro/go-micro/registry"
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"golang.org/x/net/context"
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)
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// NodeSelector is used to Retrieve a node to which a request
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// should be routed. It takes context and Request and returns a
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// single node. If a node cannot be selected it should return
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// an error. Response is called to inform the selector of the
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// response from a client call. Reset is called to zero out
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// any state.
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type NodeSelector interface {
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Select(context.Context, Request) (*registry.Node, error)
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Response(*registry.Node, error)
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Reset()
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}
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func init() {
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rand.Seed(time.Now().UnixNano())
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}
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// Built in random hashed node selector
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type nodeSelector struct {
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r registry.Registry
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}
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func (n *nodeSelector) Select(ctx context.Context, req Request) (*registry.Node, error) {
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service, err := n.r.GetService(req.Service())
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if err != nil {
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return nil, errors.InternalServerError("go.micro.client", err.Error())
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}
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if len(service) == 0 {
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return nil, errors.NotFound("go.micro.client", "Service not found")
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}
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i := rand.Int()
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j := i % len(service)
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if len(service[j].Nodes) == 0 {
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return nil, errors.NotFound("go.micro.client", "Service not found")
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}
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k := i % len(service[j].Nodes)
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return service[j].Nodes[k], nil
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}
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func (n *nodeSelector) Response(node *registry.Node, err error) {
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return
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}
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func (n *nodeSelector) Reset() {
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return
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}
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@ -1,70 +0,0 @@
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package client
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import (
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"testing"
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"github.com/micro/go-micro/registry"
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"golang.org/x/net/context"
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)
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type mockRegistry struct{}
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func (m *mockRegistry) GetService(service string) ([]*registry.Service, error) {
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return []*registry.Service{
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{
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Name: "foo",
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Version: "1.0.0",
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Nodes: []*registry.Node{
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{
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Id: "foo-123",
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Address: "localhost",
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Port: 9999,
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},
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},
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},
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{
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Name: "foo",
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Version: "1.0.1",
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Nodes: []*registry.Node{
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{
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Id: "foo-321",
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Address: "localhost",
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Port: 6666,
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},
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},
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},
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}, nil
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}
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func (m *mockRegistry) ListServices() ([]*registry.Service, error) {
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return []*registry.Service{}, nil
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}
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func (m *mockRegistry) Register(s *registry.Service) error {
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return nil
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}
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func (m *mockRegistry) Deregister(s *registry.Service) error {
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return nil
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}
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func (m *mockRegistry) Watch() (registry.Watcher, error) {
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return nil, nil
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}
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func TestNodeSelector(t *testing.T) {
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counts := map[string]int{}
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n := &nodeSelector{
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&mockRegistry{},
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}
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for i := 0; i < 100; i++ {
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n, err := n.Select(context.Background(), newRpcRequest("foo", "Foo.Bar", nil, ""))
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if err != nil {
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t.Errorf("Expected node, got err: %v", err)
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}
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counts[n.Id]++
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}
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t.Logf("Counts %v", counts)
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}
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@ -4,6 +4,7 @@ import (
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"github.com/micro/go-micro/broker"
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"github.com/micro/go-micro/codec"
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"github.com/micro/go-micro/registry"
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"github.com/micro/go-micro/selector"
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"github.com/micro/go-micro/transport"
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)
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@ -12,12 +13,14 @@ type options struct {
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broker broker.Broker
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codecs map[string]codec.NewCodec
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registry registry.Registry
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selector selector.Selector
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transport transport.Transport
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wrappers []Wrapper
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selector Selector
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}
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type callOptions struct{}
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type callOptions struct {
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selectOptions []selector.SelectOption
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}
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type publishOptions struct{}
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@ -57,7 +60,7 @@ func Transport(t transport.Transport) Option {
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}
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// Select is used to select a node to route a request to
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func Select(s Selector) Option {
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func Selector(s selector.Selector) Option {
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return func(o *options) {
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o.selector = s
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}
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@ -69,3 +72,11 @@ func Wrap(w Wrapper) Option {
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o.wrappers = append(o.wrappers, w)
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}
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}
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// Call Options
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func WithSelectOption(so selector.SelectOption) CallOption {
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return func(o *callOptions) {
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o.selectOptions = append(o.selectOptions, so)
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}
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}
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@ -10,6 +10,7 @@ import (
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c "github.com/micro/go-micro/context"
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"github.com/micro/go-micro/errors"
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"github.com/micro/go-micro/registry"
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"github.com/micro/go-micro/selector"
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"github.com/micro/go-micro/transport"
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"golang.org/x/net/context"
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@ -18,11 +19,9 @@ import (
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type rpcClient struct {
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once sync.Once
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opts options
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sel NodeSelector
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}
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func newRpcClient(opt ...Option) Client {
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var sel NodeSelector
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var once sync.Once
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opts := options{
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@ -37,28 +36,27 @@ func newRpcClient(opt ...Option) Client {
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opts.contentType = defaultContentType
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}
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if opts.transport == nil {
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opts.transport = transport.DefaultTransport
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if opts.broker == nil {
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opts.broker = broker.DefaultBroker
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}
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if opts.registry == nil {
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opts.registry = registry.DefaultRegistry
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}
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if opts.broker == nil {
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opts.broker = broker.DefaultBroker
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if opts.selector == nil {
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opts.selector = selector.NewSelector(
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selector.Registry(opts.registry),
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)
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}
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if opts.selector != nil {
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sel = opts.selector(opts.registry)
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} else {
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sel = &nodeSelector{opts.registry}
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if opts.transport == nil {
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opts.transport = transport.DefaultTransport
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}
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rc := &rpcClient{
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once: once,
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opts: opts,
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sel: sel,
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}
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c := Client(rc)
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@ -153,9 +151,23 @@ func (r *rpcClient) CallRemote(ctx context.Context, address string, request Requ
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}
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func (r *rpcClient) Call(ctx context.Context, request Request, response interface{}, opts ...CallOption) error {
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node, err := r.sel.Select(ctx, request)
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if err != nil {
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return err
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var copts callOptions
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for _, opt := range opts {
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opt(&copts)
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}
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next, err := r.opts.selector.Select(request.Service(), copts.selectOptions...)
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if err != nil && err == selector.ErrNotFound {
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return errors.NotFound("go.micro.client", err.Error())
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} else if err != nil {
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return errors.InternalServerError("go.micro.client", err.Error())
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}
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node, err := next()
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if err != nil && err == selector.ErrNotFound {
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return errors.NotFound("go.micro.client", err.Error())
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} else if err != nil {
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return errors.InternalServerError("go.micro.client", err.Error())
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}
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address := node.Address
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@ -164,7 +176,7 @@ func (r *rpcClient) Call(ctx context.Context, request Request, response interfac
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}
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err = r.call(ctx, address, request, response)
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r.sel.Response(node, err)
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r.opts.selector.Mark(request.Service(), node, err)
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return err
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}
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@ -173,9 +185,23 @@ func (r *rpcClient) StreamRemote(ctx context.Context, address string, request Re
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}
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func (r *rpcClient) Stream(ctx context.Context, request Request, responseChan interface{}, opts ...CallOption) (Streamer, error) {
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node, err := r.sel.Select(ctx, request)
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if err != nil {
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return nil, err
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var copts callOptions
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for _, opt := range opts {
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opt(&copts)
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}
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next, err := r.opts.selector.Select(request.Service(), copts.selectOptions...)
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if err != nil && err == selector.ErrNotFound {
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return nil, errors.NotFound("go.micro.client", err.Error())
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} else if err != nil {
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return nil, errors.InternalServerError("go.micro.client", err.Error())
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}
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node, err := next()
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if err != nil && err == selector.ErrNotFound {
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return nil, errors.NotFound("go.micro.client", err.Error())
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} else if err != nil {
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return nil, errors.InternalServerError("go.micro.client", err.Error())
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}
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address := node.Address
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@ -184,7 +210,7 @@ func (r *rpcClient) Stream(ctx context.Context, request Request, responseChan in
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}
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stream, err := r.stream(ctx, address, request, responseChan)
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r.sel.Response(node, err)
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r.opts.selector.Mark(request.Service(), node, err)
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return stream, err
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}
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|
15
cmd/cmd.go
15
cmd/cmd.go
@ -19,6 +19,7 @@ import (
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"github.com/micro/go-micro/broker"
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"github.com/micro/go-micro/client"
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"github.com/micro/go-micro/registry"
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"github.com/micro/go-micro/selector"
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"github.com/micro/go-micro/server"
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"github.com/micro/go-micro/transport"
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"github.com/pborman/uuid"
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@ -80,6 +81,12 @@ var (
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EnvVar: "MICRO_REGISTRY_ADDRESS",
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Usage: "Comma-separated list of registry addresses",
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},
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cli.StringFlag{
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Name: "selector",
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EnvVar: "MICRO_SELECTOR",
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Value: "selector",
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Usage: "Selector used to pick nodes for querying. random, roundrobin, blacklist",
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},
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cli.StringFlag{
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Name: "transport",
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EnvVar: "MICRO_TRANSPORT",
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@ -137,6 +144,10 @@ var (
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"consul": registry.NewRegistry,
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}
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Selectors = map[string]func(...selector.Option) selector.Selector{
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"random": selector.NewSelector,
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}
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Transports = map[string]func([]string, ...transport.Option) transport.Transport{
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"http": transport.NewTransport,
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}
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@ -214,6 +225,10 @@ func Setup(c *cli.Context) error {
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registry.DefaultRegistry = r(strings.Split(c.String("registry_address"), ","))
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}
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if s, ok := Selectors[c.String("selector")]; ok {
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selector.DefaultSelector = s(selector.Registry(registry.DefaultRegistry))
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}
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if t, ok := Transports[c.String("transport")]; ok {
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transport.DefaultTransport = t(strings.Split(c.String("transport_address"), ","))
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}
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|
88
examples/client/dc_filter/dc_filter.go
Normal file
88
examples/client/dc_filter/dc_filter.go
Normal file
@ -0,0 +1,88 @@
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package main
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import (
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"fmt"
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"math/rand"
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"time"
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"github.com/micro/go-micro/client"
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"github.com/micro/go-micro/cmd"
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c "github.com/micro/go-micro/context"
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"github.com/micro/go-micro/registry"
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"github.com/micro/go-micro/selector"
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"golang.org/x/net/context"
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example "github.com/micro/go-micro/examples/server/proto/example"
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)
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|
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func init() {
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rand.Seed(time.Now().Unix())
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}
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// A Wrapper that creates a Datacenter Selector Option
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type dcWrapper struct {
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client.Client
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}
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|
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func (dc *dcWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
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md, _ := c.GetMetadata(ctx)
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|
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filter := func(services []*registry.Service) []*registry.Service {
|
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for _, service := range services {
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var nodes []*registry.Node
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for _, node := range service.Nodes {
|
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if node.Metadata["datacenter"] == md["datacenter"] {
|
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nodes = append(nodes, node)
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}
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}
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service.Nodes = nodes
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}
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return services
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}
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|
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callOptions := append(opts, client.WithSelectOption(
|
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selector.Filter(filter),
|
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))
|
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|
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fmt.Printf("[DC Wrapper] filtering for datacenter %s\n", md["datacenter"])
|
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return dc.Client.Call(ctx, req, rsp, callOptions...)
|
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}
|
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|
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func NewDCWrapper(c client.Client) client.Client {
|
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return &dcWrapper{c}
|
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}
|
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|
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func call(i int) {
|
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// Create new request to service go.micro.srv.example, method Example.Call
|
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req := client.NewRequest("go.micro.srv.example", "Example.Call", &example.Request{
|
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Name: "John",
|
||||
})
|
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|
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// create context with metadata
|
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ctx := c.WithMetadata(context.Background(), map[string]string{
|
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"datacenter": "local",
|
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})
|
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|
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rsp := &example.Response{}
|
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|
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// Call service
|
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if err := client.Call(ctx, req, rsp); err != nil {
|
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fmt.Println("call err: ", err, rsp)
|
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return
|
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}
|
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|
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fmt.Println("Call:", i, "rsp:", rsp.Msg)
|
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}
|
||||
|
||||
func main() {
|
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cmd.Init()
|
||||
|
||||
client.DefaultClient = client.NewClient(
|
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client.Wrap(NewDCWrapper),
|
||||
)
|
||||
|
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fmt.Println("\n--- Call example ---\n")
|
||||
for i := 0; i < 10; i++ {
|
||||
call(i)
|
||||
}
|
||||
}
|
119
examples/client/dc_selector/dc_selector.go
Normal file
119
examples/client/dc_selector/dc_selector.go
Normal file
@ -0,0 +1,119 @@
|
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package main
|
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|
||||
import (
|
||||
"fmt"
|
||||
"math/rand"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/client"
|
||||
"github.com/micro/go-micro/cmd"
|
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"github.com/micro/go-micro/registry"
|
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"github.com/micro/go-micro/selector"
|
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"golang.org/x/net/context"
|
||||
|
||||
example "github.com/micro/go-micro/examples/server/proto/example"
|
||||
)
|
||||
|
||||
// Built in random hashed node selector
|
||||
type dcSelector struct {
|
||||
opts selector.Options
|
||||
}
|
||||
|
||||
var (
|
||||
datacenter = "local"
|
||||
)
|
||||
|
||||
func init() {
|
||||
rand.Seed(time.Now().Unix())
|
||||
}
|
||||
|
||||
func (n *dcSelector) Select(service string, opts ...selector.SelectOption) (selector.Next, error) {
|
||||
services, err := n.opts.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if len(services) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var nodes []*registry.Node
|
||||
|
||||
// Filter the nodes for datacenter
|
||||
for _, service := range services {
|
||||
for _, node := range service.Nodes {
|
||||
if node.Metadata["datacenter"] == datacenter {
|
||||
nodes = append(nodes, node)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if len(nodes) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var i int
|
||||
var mtx sync.Mutex
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
mtx.Lock()
|
||||
defer mtx.Unlock()
|
||||
i++
|
||||
return nodes[i%len(nodes)], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (n *dcSelector) Mark(service string, node *registry.Node, err error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (n *dcSelector) Reset(service string) {
|
||||
return
|
||||
}
|
||||
|
||||
func (n *dcSelector) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
// Return a new first node selector
|
||||
func DCSelector(opts ...selector.Option) selector.Selector {
|
||||
var sopts selector.Options
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
if sopts.Registry == nil {
|
||||
sopts.Registry = registry.DefaultRegistry
|
||||
}
|
||||
return &dcSelector{sopts}
|
||||
}
|
||||
|
||||
func call(i int) {
|
||||
// Create new request to service go.micro.srv.example, method Example.Call
|
||||
req := client.NewRequest("go.micro.srv.example", "Example.Call", &example.Request{
|
||||
Name: "John",
|
||||
})
|
||||
|
||||
rsp := &example.Response{}
|
||||
|
||||
// Call service
|
||||
if err := client.Call(context.Background(), req, rsp); err != nil {
|
||||
fmt.Println("call err: ", err, rsp)
|
||||
return
|
||||
}
|
||||
|
||||
fmt.Println("Call:", i, "rsp:", rsp.Msg)
|
||||
}
|
||||
|
||||
func main() {
|
||||
cmd.Init()
|
||||
|
||||
client.DefaultClient = client.NewClient(
|
||||
client.Selector(DCSelector()),
|
||||
)
|
||||
|
||||
fmt.Println("\n--- Call example ---\n")
|
||||
for i := 0; i < 10; i++ {
|
||||
call(i)
|
||||
}
|
||||
}
|
@ -1,87 +0,0 @@
|
||||
package main
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math/rand"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/client"
|
||||
"github.com/micro/go-micro/cmd"
|
||||
"github.com/micro/go-micro/errors"
|
||||
example "github.com/micro/go-micro/examples/server/proto/example"
|
||||
"github.com/micro/go-micro/registry"
|
||||
"golang.org/x/net/context"
|
||||
)
|
||||
|
||||
func init() {
|
||||
rand.Seed(time.Now().Unix())
|
||||
}
|
||||
|
||||
// Built in random hashed node selector
|
||||
type nodeSelector struct {
|
||||
r registry.Registry
|
||||
}
|
||||
|
||||
func (n *nodeSelector) Select(ctx context.Context, req client.Request) (*registry.Node, error) {
|
||||
service, err := n.r.GetService(req.Service())
|
||||
if err != nil {
|
||||
return nil, errors.InternalServerError("go.micro.client", err.Error())
|
||||
}
|
||||
|
||||
if len(service) == 0 {
|
||||
return nil, errors.NotFound("go.micro.client", "Service not found")
|
||||
}
|
||||
|
||||
i := rand.Int()
|
||||
j := i % len(service)
|
||||
|
||||
if len(service[j].Nodes) == 0 {
|
||||
return nil, errors.NotFound("go.micro.client", "Service not found")
|
||||
}
|
||||
|
||||
k := i % len(service[j].Nodes)
|
||||
return service[j].Nodes[k], nil
|
||||
}
|
||||
|
||||
func (n *nodeSelector) Response(node *registry.Node, err error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (n *nodeSelector) Reset() {
|
||||
return
|
||||
}
|
||||
|
||||
// Return a new random node selector
|
||||
func RandomSelector(r registry.Registry) client.NodeSelector {
|
||||
return &nodeSelector{r}
|
||||
}
|
||||
|
||||
func call(i int) {
|
||||
// Create new request to service go.micro.srv.example, method Example.Call
|
||||
req := client.NewRequest("go.micro.srv.example", "Example.Call", &example.Request{
|
||||
Name: "John",
|
||||
})
|
||||
|
||||
rsp := &example.Response{}
|
||||
|
||||
// Call service
|
||||
if err := client.Call(context.Background(), req, rsp); err != nil {
|
||||
fmt.Println("call err: ", err, rsp)
|
||||
return
|
||||
}
|
||||
|
||||
fmt.Println("Call:", i, "rsp:", rsp.Msg)
|
||||
}
|
||||
|
||||
func main() {
|
||||
cmd.Init()
|
||||
|
||||
client.DefaultClient = client.NewClient(
|
||||
client.Select(RandomSelector),
|
||||
)
|
||||
|
||||
fmt.Println("\n--- Call example ---\n")
|
||||
for i := 0; i < 10; i++ {
|
||||
call(i)
|
||||
}
|
||||
}
|
109
examples/client/selector/selector.go
Normal file
109
examples/client/selector/selector.go
Normal file
@ -0,0 +1,109 @@
|
||||
package main
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math/rand"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/client"
|
||||
"github.com/micro/go-micro/cmd"
|
||||
example "github.com/micro/go-micro/examples/server/proto/example"
|
||||
"github.com/micro/go-micro/registry"
|
||||
"github.com/micro/go-micro/selector"
|
||||
"golang.org/x/net/context"
|
||||
)
|
||||
|
||||
func init() {
|
||||
rand.Seed(time.Now().Unix())
|
||||
}
|
||||
|
||||
// Built in random hashed node selector
|
||||
type firstNodeSelector struct {
|
||||
opts selector.Options
|
||||
}
|
||||
|
||||
func (n *firstNodeSelector) Select(service string, opts ...selector.SelectOption) (selector.Next, error) {
|
||||
services, err := n.opts.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
if len(services) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var sopts selector.SelectOptions
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
for _, filter := range sopts.Filters {
|
||||
services = filter(services)
|
||||
}
|
||||
|
||||
if len(services) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
if len(services[0].Nodes) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
return services[0].Nodes[0], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (n *firstNodeSelector) Mark(service string, node *registry.Node, err error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (n *firstNodeSelector) Reset(service string) {
|
||||
return
|
||||
}
|
||||
|
||||
func (n *firstNodeSelector) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
// Return a new first node selector
|
||||
func FirstNodeSelector(opts ...selector.Option) selector.Selector {
|
||||
var sopts selector.Options
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
if sopts.Registry == nil {
|
||||
sopts.Registry = registry.DefaultRegistry
|
||||
}
|
||||
return &firstNodeSelector{sopts}
|
||||
}
|
||||
|
||||
func call(i int) {
|
||||
// Create new request to service go.micro.srv.example, method Example.Call
|
||||
req := client.NewRequest("go.micro.srv.example", "Example.Call", &example.Request{
|
||||
Name: "John",
|
||||
})
|
||||
|
||||
rsp := &example.Response{}
|
||||
|
||||
// Call service
|
||||
if err := client.Call(context.Background(), req, rsp); err != nil {
|
||||
fmt.Println("call err: ", err, rsp)
|
||||
return
|
||||
}
|
||||
|
||||
fmt.Println("Call:", i, "rsp:", rsp.Msg)
|
||||
}
|
||||
|
||||
func main() {
|
||||
cmd.Init()
|
||||
|
||||
client.DefaultClient = client.NewClient(
|
||||
client.Selector(FirstNodeSelector()),
|
||||
)
|
||||
|
||||
fmt.Println("\n--- Call example ---\n")
|
||||
for i := 0; i < 10; i++ {
|
||||
call(i)
|
||||
}
|
||||
}
|
@ -31,9 +31,13 @@ func main() {
|
||||
// optionally setup command line usage
|
||||
cmd.Init()
|
||||
|
||||
md := server.Config().Metadata()
|
||||
md["datacenter"] = "local"
|
||||
|
||||
server.DefaultServer = server.NewServer(
|
||||
server.WrapHandler(logWrapper),
|
||||
server.WrapSubscriber(logSubWrapper),
|
||||
server.Metadata(md),
|
||||
)
|
||||
|
||||
// Initialise Server
|
||||
|
70
registry/mock/mock.go
Normal file
70
registry/mock/mock.go
Normal file
@ -0,0 +1,70 @@
|
||||
package mock
|
||||
|
||||
import (
|
||||
"github.com/micro/go-micro/registry"
|
||||
)
|
||||
|
||||
type MockRegistry struct{}
|
||||
|
||||
func (m *MockRegistry) GetService(service string) ([]*registry.Service, error) {
|
||||
return []*registry.Service{
|
||||
{
|
||||
Name: "foo",
|
||||
Version: "1.0.0",
|
||||
Nodes: []*registry.Node{
|
||||
{
|
||||
Id: "foo-1.0.0-123",
|
||||
Address: "localhost",
|
||||
Port: 9999,
|
||||
},
|
||||
{
|
||||
Id: "foo-1.0.0-321",
|
||||
Address: "localhost",
|
||||
Port: 9999,
|
||||
},
|
||||
},
|
||||
},
|
||||
{
|
||||
Name: "foo",
|
||||
Version: "1.0.1",
|
||||
Nodes: []*registry.Node{
|
||||
{
|
||||
Id: "foo-1.0.1-321",
|
||||
Address: "localhost",
|
||||
Port: 6666,
|
||||
},
|
||||
},
|
||||
},
|
||||
{
|
||||
Name: "foo",
|
||||
Version: "1.0.3",
|
||||
Nodes: []*registry.Node{
|
||||
{
|
||||
Id: "foo-1.0.3-345",
|
||||
Address: "localhost",
|
||||
Port: 8888,
|
||||
},
|
||||
},
|
||||
},
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (m *MockRegistry) ListServices() ([]*registry.Service, error) {
|
||||
return []*registry.Service{}, nil
|
||||
}
|
||||
|
||||
func (m *MockRegistry) Register(s *registry.Service) error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func (m *MockRegistry) Deregister(s *registry.Service) error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func (m *MockRegistry) Watch() (registry.Watcher, error) {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
func NewRegistry() *MockRegistry {
|
||||
return &MockRegistry{}
|
||||
}
|
169
selector/blacklist/black_list_selector.go
Normal file
169
selector/blacklist/black_list_selector.go
Normal file
@ -0,0 +1,169 @@
|
||||
package blacklist
|
||||
|
||||
import (
|
||||
"math/rand"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/cmd"
|
||||
"github.com/micro/go-micro/registry"
|
||||
"github.com/micro/go-micro/selector"
|
||||
)
|
||||
|
||||
type blackListNode struct {
|
||||
age time.Time
|
||||
id string
|
||||
service string
|
||||
}
|
||||
|
||||
type blackListSelector struct {
|
||||
so selector.Options
|
||||
ttl int64
|
||||
exit chan bool
|
||||
once sync.Once
|
||||
|
||||
sync.RWMutex
|
||||
bl map[string]blackListNode
|
||||
}
|
||||
|
||||
func init() {
|
||||
cmd.Selectors["blacklist"] = NewSelector
|
||||
rand.Seed(time.Now().Unix())
|
||||
}
|
||||
|
||||
func (r *blackListSelector) purge() {
|
||||
now := time.Now()
|
||||
r.Lock()
|
||||
for k, v := range r.bl {
|
||||
if d := v.age.Sub(now); d.Seconds() < 0 {
|
||||
delete(r.bl, k)
|
||||
}
|
||||
}
|
||||
r.Unlock()
|
||||
}
|
||||
|
||||
func (r *blackListSelector) run() {
|
||||
t := time.NewTicker(time.Duration(r.ttl) * time.Second)
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-r.exit:
|
||||
t.Stop()
|
||||
return
|
||||
case <-t.C:
|
||||
r.purge()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (r *blackListSelector) Select(service string, opts ...selector.SelectOption) (selector.Next, error) {
|
||||
var sopts selector.SelectOptions
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
// get the service
|
||||
services, err := r.so.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// apply the filters
|
||||
for _, filter := range sopts.Filters {
|
||||
services = filter(services)
|
||||
}
|
||||
|
||||
// if there's nothing left, return
|
||||
if len(services) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var nodes []*registry.Node
|
||||
|
||||
for _, service := range services {
|
||||
for _, node := range service.Nodes {
|
||||
nodes = append(nodes, node)
|
||||
}
|
||||
}
|
||||
|
||||
if len(nodes) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
var viable []*registry.Node
|
||||
|
||||
r.RLock()
|
||||
for _, node := range nodes {
|
||||
if _, ok := r.bl[node.Id]; !ok {
|
||||
viable = append(viable, node)
|
||||
}
|
||||
}
|
||||
r.RUnlock()
|
||||
|
||||
if len(viable) == 0 {
|
||||
return nil, selector.ErrNoneAvailable
|
||||
}
|
||||
|
||||
return viable[rand.Int()%len(viable)], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (r *blackListSelector) Mark(service string, node *registry.Node, err error) {
|
||||
r.Lock()
|
||||
defer r.Unlock()
|
||||
if err == nil {
|
||||
delete(r.bl, node.Id)
|
||||
return
|
||||
}
|
||||
|
||||
r.bl[node.Id] = blackListNode{
|
||||
age: time.Now().Add(time.Duration(r.ttl) * time.Second),
|
||||
id: node.Id,
|
||||
service: service,
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func (r *blackListSelector) Reset(service string) {
|
||||
r.Lock()
|
||||
defer r.Unlock()
|
||||
for k, v := range r.bl {
|
||||
if v.service == service {
|
||||
delete(r.bl, k)
|
||||
}
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func (r *blackListSelector) Close() error {
|
||||
r.once.Do(func() {
|
||||
close(r.exit)
|
||||
})
|
||||
return nil
|
||||
}
|
||||
|
||||
func NewSelector(opts ...selector.Option) selector.Selector {
|
||||
var sopts selector.Options
|
||||
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
if sopts.Registry == nil {
|
||||
sopts.Registry = registry.DefaultRegistry
|
||||
}
|
||||
|
||||
var once sync.Once
|
||||
bl := &blackListSelector{
|
||||
once: once,
|
||||
so: sopts,
|
||||
ttl: 60,
|
||||
bl: make(map[string]blackListNode),
|
||||
exit: make(chan bool),
|
||||
}
|
||||
|
||||
go bl.run()
|
||||
|
||||
return bl
|
||||
}
|
73
selector/blacklist/black_list_selector_test.go
Normal file
73
selector/blacklist/black_list_selector_test.go
Normal file
@ -0,0 +1,73 @@
|
||||
package blacklist
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"testing"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/registry/mock"
|
||||
"github.com/micro/go-micro/selector"
|
||||
)
|
||||
|
||||
func TestBlackListSelector(t *testing.T) {
|
||||
counts := map[string]int{}
|
||||
|
||||
bl := &blackListSelector{
|
||||
so: selector.Options{
|
||||
Registry: mock.NewRegistry(),
|
||||
},
|
||||
ttl: 2,
|
||||
bl: make(map[string]blackListNode),
|
||||
exit: make(chan bool),
|
||||
}
|
||||
|
||||
go bl.run()
|
||||
defer bl.Close()
|
||||
|
||||
next, err := bl.Select("foo")
|
||||
if err != nil {
|
||||
t.Errorf("Unexpected error calling bl select: %v", err)
|
||||
}
|
||||
|
||||
for i := 0; i < 100; i++ {
|
||||
node, err := next()
|
||||
if err != nil {
|
||||
t.Errorf("Expected node err, got err: %v", err)
|
||||
}
|
||||
counts[node.Id]++
|
||||
}
|
||||
|
||||
t.Logf("BlackList Counts %v", counts)
|
||||
|
||||
// test blacklisting
|
||||
for i := 0; i < 4; i++ {
|
||||
node, err := next()
|
||||
if err != nil {
|
||||
t.Errorf("Expected node err, got err: %v", err)
|
||||
}
|
||||
bl.Mark("foo", node, errors.New("blacklist"))
|
||||
}
|
||||
if node, err := next(); err != selector.ErrNoneAvailable {
|
||||
t.Errorf("Expected none available err, got node %v err %v", node, err)
|
||||
}
|
||||
time.Sleep(time.Second * time.Duration(bl.ttl) * 2)
|
||||
if _, err := next(); err != nil {
|
||||
t.Errorf("Unexpected err %v", err)
|
||||
}
|
||||
|
||||
// test resetting
|
||||
for i := 0; i < 4; i++ {
|
||||
node, err := next()
|
||||
if err != nil {
|
||||
t.Errorf("Unexpected err: %v", err)
|
||||
}
|
||||
bl.Mark("foo", node, errors.New("blacklist"))
|
||||
}
|
||||
if node, err := next(); err != selector.ErrNoneAvailable {
|
||||
t.Errorf("Expected none available err, got node %v err %v", node, err)
|
||||
}
|
||||
bl.Reset("foo")
|
||||
if _, err := next(); err != nil {
|
||||
t.Errorf("Unexpected err %v", err)
|
||||
}
|
||||
}
|
34
selector/options.go
Normal file
34
selector/options.go
Normal file
@ -0,0 +1,34 @@
|
||||
package selector
|
||||
|
||||
import (
|
||||
"github.com/micro/go-micro/registry"
|
||||
)
|
||||
|
||||
type Options struct {
|
||||
Registry registry.Registry
|
||||
}
|
||||
|
||||
type SelectOptions struct {
|
||||
Filters []SelectFilter
|
||||
}
|
||||
|
||||
// Option used to initialise the selector
|
||||
type Option func(*Options)
|
||||
|
||||
// SelectOption used when making a select call
|
||||
type SelectOption func(*SelectOptions)
|
||||
|
||||
// Registry sets the registry used by the selector
|
||||
func Registry(r registry.Registry) Option {
|
||||
return func(o *Options) {
|
||||
o.Registry = r
|
||||
}
|
||||
}
|
||||
|
||||
// Filter adds a filter function to the list of filters
|
||||
// used during the Select call.
|
||||
func Filter(fn SelectFilter) SelectOption {
|
||||
return func(o *SelectOptions) {
|
||||
o.Filters = append(o.Filters, fn)
|
||||
}
|
||||
}
|
14
selector/random/random.go
Normal file
14
selector/random/random.go
Normal file
@ -0,0 +1,14 @@
|
||||
package random
|
||||
|
||||
import (
|
||||
"github.com/micro/go-micro/cmd"
|
||||
"github.com/micro/go-micro/selector"
|
||||
)
|
||||
|
||||
func init() {
|
||||
cmd.Selectors["random"] = NewSelector
|
||||
}
|
||||
|
||||
func NewSelector(opts ...selector.Option) selector.Selector {
|
||||
return selector.NewSelector(opts...)
|
||||
}
|
89
selector/random_selector.go
Normal file
89
selector/random_selector.go
Normal file
@ -0,0 +1,89 @@
|
||||
package selector
|
||||
|
||||
import (
|
||||
"math/rand"
|
||||
"time"
|
||||
|
||||
"github.com/micro/go-micro/registry"
|
||||
)
|
||||
|
||||
type randomSelector struct {
|
||||
so Options
|
||||
}
|
||||
|
||||
func init() {
|
||||
rand.Seed(time.Now().Unix())
|
||||
}
|
||||
|
||||
func (r *randomSelector) Select(service string, opts ...SelectOption) (Next, error) {
|
||||
var sopts SelectOptions
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
// get the service
|
||||
services, err := r.so.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// apply the filters
|
||||
for _, filter := range sopts.Filters {
|
||||
services = filter(services)
|
||||
}
|
||||
|
||||
// if there's nothing left, return
|
||||
if len(services) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
var nodes []*registry.Node
|
||||
|
||||
for _, service := range services {
|
||||
for _, node := range service.Nodes {
|
||||
nodes = append(nodes, node)
|
||||
}
|
||||
}
|
||||
|
||||
if len(nodes) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
i := rand.Int()
|
||||
j := i % len(services)
|
||||
|
||||
if len(services[j].Nodes) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
k := i % len(services[j].Nodes)
|
||||
return services[j].Nodes[k], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (r *randomSelector) Mark(service string, node *registry.Node, err error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (r *randomSelector) Reset(service string) {
|
||||
return
|
||||
}
|
||||
|
||||
func (r *randomSelector) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func newRandomSelector(opts ...Option) Selector {
|
||||
var sopts Options
|
||||
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
if sopts.Registry == nil {
|
||||
sopts.Registry = registry.DefaultRegistry
|
||||
}
|
||||
|
||||
return &randomSelector{sopts}
|
||||
}
|
32
selector/random_selector_test.go
Normal file
32
selector/random_selector_test.go
Normal file
@ -0,0 +1,32 @@
|
||||
package selector
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/micro/go-micro/registry/mock"
|
||||
)
|
||||
|
||||
func TestRandomSelector(t *testing.T) {
|
||||
counts := map[string]int{}
|
||||
|
||||
bl := &randomSelector{
|
||||
so: Options{
|
||||
Registry: mock.NewRegistry(),
|
||||
},
|
||||
}
|
||||
|
||||
next, err := bl.Select("foo")
|
||||
if err != nil {
|
||||
t.Errorf("Unexpected error calling random select: %v", err)
|
||||
}
|
||||
|
||||
for i := 0; i < 100; i++ {
|
||||
node, err := next()
|
||||
if err != nil {
|
||||
t.Errorf("Expected node err, got err: %v", err)
|
||||
}
|
||||
counts[node.Id]++
|
||||
}
|
||||
|
||||
t.Logf("Random Counts %v", counts)
|
||||
}
|
88
selector/roundrobin/round_robin_selector.go
Normal file
88
selector/roundrobin/round_robin_selector.go
Normal file
@ -0,0 +1,88 @@
|
||||
package roundrobin
|
||||
|
||||
import (
|
||||
"sync"
|
||||
|
||||
"github.com/micro/go-micro/cmd"
|
||||
"github.com/micro/go-micro/registry"
|
||||
"github.com/micro/go-micro/selector"
|
||||
)
|
||||
|
||||
type roundRobinSelector struct {
|
||||
so selector.Options
|
||||
}
|
||||
|
||||
func init() {
|
||||
cmd.Selectors["roundrobin"] = NewSelector
|
||||
}
|
||||
|
||||
func (r *roundRobinSelector) Select(service string, opts ...selector.SelectOption) (selector.Next, error) {
|
||||
var sopts selector.SelectOptions
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
// get the service
|
||||
services, err := r.so.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// apply the filters
|
||||
for _, filter := range sopts.Filters {
|
||||
services = filter(services)
|
||||
}
|
||||
|
||||
// if there's nothing left, return
|
||||
if len(services) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var nodes []*registry.Node
|
||||
|
||||
for _, service := range services {
|
||||
for _, node := range service.Nodes {
|
||||
nodes = append(nodes, node)
|
||||
}
|
||||
}
|
||||
|
||||
if len(nodes) == 0 {
|
||||
return nil, selector.ErrNotFound
|
||||
}
|
||||
|
||||
var i int
|
||||
var mtx sync.Mutex
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
mtx.Lock()
|
||||
defer mtx.Unlock()
|
||||
i++
|
||||
return nodes[i%len(nodes)], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
func (r *roundRobinSelector) Mark(service string, node *registry.Node, err error) {
|
||||
return
|
||||
}
|
||||
|
||||
func (r *roundRobinSelector) Reset(service string) {
|
||||
return
|
||||
}
|
||||
|
||||
func (r *roundRobinSelector) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func NewSelector(opts ...selector.Option) selector.Selector {
|
||||
var sopts selector.Options
|
||||
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
if sopts.Registry == nil {
|
||||
sopts.Registry = registry.DefaultRegistry
|
||||
}
|
||||
|
||||
return &roundRobinSelector{sopts}
|
||||
}
|
33
selector/roundrobin/round_robin_selector_test.go
Normal file
33
selector/roundrobin/round_robin_selector_test.go
Normal file
@ -0,0 +1,33 @@
|
||||
package roundrobin
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
"github.com/micro/go-micro/registry/mock"
|
||||
"github.com/micro/go-micro/selector"
|
||||
)
|
||||
|
||||
func TestRoundRobinSelector(t *testing.T) {
|
||||
counts := map[string]int{}
|
||||
|
||||
rr := &roundRobinSelector{
|
||||
so: selector.Options{
|
||||
Registry: mock.NewRegistry(),
|
||||
},
|
||||
}
|
||||
|
||||
next, err := rr.Select("foo")
|
||||
if err != nil {
|
||||
t.Errorf("Unexpected error calling rr select: %v", err)
|
||||
}
|
||||
|
||||
for i := 0; i < 100; i++ {
|
||||
node, err := next()
|
||||
if err != nil {
|
||||
t.Errorf("Expected node err, got err: %v", err)
|
||||
}
|
||||
counts[node.Id]++
|
||||
}
|
||||
|
||||
t.Logf("Round Robin Counts %v", counts)
|
||||
}
|
93
selector/selector.go
Normal file
93
selector/selector.go
Normal file
@ -0,0 +1,93 @@
|
||||
/*
|
||||
The Selector package provides a way to algorithmically filter and return
|
||||
nodes required by the client or any other system. Selector's implemented
|
||||
by Micro build on the registry but it's of optional use. One could
|
||||
provide a static Selector that has a fixed pool.
|
||||
|
||||
func (r *randomSelector) Select(service string, opts ...SelectOption) (Next, error) {
|
||||
var sopts SelectOptions
|
||||
for _, opt := range opts {
|
||||
opt(&sopts)
|
||||
}
|
||||
|
||||
// get the service
|
||||
services, err := r.so.Registry.GetService(service)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// apply the filters
|
||||
for _, filter := range sopts.Filters {
|
||||
services = filter(services)
|
||||
}
|
||||
|
||||
// if there's nothing left, return
|
||||
if len(services) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
var nodes []*registry.Node
|
||||
|
||||
for _, service := range services {
|
||||
for _, node := range service.Nodes {
|
||||
nodes = append(nodes, node)
|
||||
}
|
||||
}
|
||||
|
||||
if len(nodes) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
return func() (*registry.Node, error) {
|
||||
i := rand.Int()
|
||||
j := i % len(services)
|
||||
|
||||
if len(services[j].Nodes) == 0 {
|
||||
return nil, ErrNotFound
|
||||
}
|
||||
|
||||
k := i % len(services[j].Nodes)
|
||||
return services[j].Nodes[k], nil
|
||||
}, nil
|
||||
}
|
||||
|
||||
|
||||
*/
|
||||
package selector
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"github.com/micro/go-micro/registry"
|
||||
)
|
||||
|
||||
// Selector builds on the registry as a mechanism to pick nodes
|
||||
// and mark their status. This allows host pools and other things
|
||||
// to be built using various algorithms.
|
||||
type Selector interface {
|
||||
// Select returns a function which should return the next node
|
||||
Select(service string, opts ...SelectOption) (Next, error)
|
||||
// Mark sets the success/error against a node
|
||||
Mark(service string, node *registry.Node, err error)
|
||||
// Reset returns state back to zero for a service
|
||||
Reset(service string)
|
||||
// Close renders the selector unusable
|
||||
Close() error
|
||||
}
|
||||
|
||||
// Next is a function that returns the next node
|
||||
// based on the selector's algorithm
|
||||
type Next func() (*registry.Node, error)
|
||||
|
||||
// SelectFilter is used to filter a service during the selection process
|
||||
type SelectFilter func([]*registry.Service) []*registry.Service
|
||||
|
||||
var (
|
||||
DefaultSelector = newRandomSelector()
|
||||
|
||||
ErrNotFound = errors.New("not found")
|
||||
ErrNoneAvailable = errors.New("none available")
|
||||
)
|
||||
|
||||
func NewSelector(opts ...Option) Selector {
|
||||
return newRandomSelector(opts...)
|
||||
}
|
Loading…
Reference in New Issue
Block a user