Move proxy/router

proxy/grpc/grpc.go

@@ -0,0 +1,158 @@
+// Package grpc transparently forwards the grpc protocol using a go-micro client.
+package grpc
+
+import (
+	"context"
+	"io"
+	"strings"
+
+	"github.com/micro/go-micro/client"
+	"github.com/micro/go-micro/client/grpc"
+	"github.com/micro/go-micro/codec"
+	"github.com/micro/go-micro/config/options"
+	"github.com/micro/go-micro/proxy"
+	"github.com/micro/go-micro/server"
+)
+
+// Proxy will transparently proxy requests to the backend.
+// If no backend is specified it will call a service using the client.
+// If the service matches the Name it will use the server.DefaultRouter.
+type Proxy struct {
+	// The proxy options
+	options.Options
+
+	// Endpoint specified the fixed endpoint to call.
+	Endpoint string
+
+	// The client to use for outbound requests
+	Client client.Client
+}
+
+// read client request and write to server
+func readLoop(r server.Request, s client.Stream) error {
+	// request to backend server
+	req := s.Request()
+
+	for {
+		// get data from client
+		//  no need to decode it
+		body, err := r.Read()
+		if err == io.EOF {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+
+		// get the header from client
+		hdr := r.Header()
+		msg := &codec.Message{
+			Type:   codec.Request,
+			Header: hdr,
+			Body:   body,
+		}
+		// write the raw request
+		err = req.Codec().Write(msg, nil)
+		if err == io.EOF {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// ServeRequest honours the server.Proxy interface
+func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server.Response) error {
+	// set default client
+	if p.Client == nil {
+		p.Client = grpc.NewClient()
+	}
+
+	opts := []client.CallOption{}
+
+	// service name
+	service := req.Service()
+	endpoint := req.Endpoint()
+
+	// call a specific backend
+	if len(p.Endpoint) > 0 {
+		// address:port
+		if parts := strings.Split(p.Endpoint, ":"); len(parts) > 1 {
+			opts = append(opts, client.WithAddress(p.Endpoint))
+			// use as service name
+		} else {
+			service = p.Endpoint
+		}
+	}
+
+	// create new request with raw bytes body
+	creq := p.Client.NewRequest(service, endpoint, nil, client.WithContentType(req.ContentType()))
+
+	// create new stream
+	stream, err := p.Client.Stream(ctx, creq, opts...)
+	if err != nil {
+		return err
+	}
+	defer stream.Close()
+
+	// create client request read loop
+	go readLoop(req, stream)
+
+	// get raw response
+	resp := stream.Response()
+
+	// create server response write loop
+	for {
+		// read backend response body
+		body, err := resp.Read()
+		if err == io.EOF {
+			return nil
+		} else if err != nil {
+			return err
+		}
+
+		// read backend response header
+		hdr := resp.Header()
+
+		// write raw response header to client
+		rsp.WriteHeader(hdr)
+
+		// write raw response body to client
+		err = rsp.Write(body)
+		if err == io.EOF {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// NewProxy returns a new grpc proxy server
+func NewProxy(opts ...options.Option) proxy.Proxy {
+	p := new(Proxy)
+	p.Options = options.NewOptions(opts...)
+	p.Options.Init(options.WithString("grpc"))
+
+	// get endpoint
+	ep, ok := p.Options.Values().Get("proxy.endpoint")
+	if ok {
+		p.Endpoint = ep.(string)
+	}
+
+	// get client
+	c, ok := p.Options.Values().Get("proxy.client")
+	if ok {
+		p.Client = c.(client.Client)
+	}
+
+	return p
+}
+
+// NewSingleHostProxy returns a router which sends requests to a single backend
+func NewSingleHostProxy(url string) *Proxy {
+	return &Proxy{
+		Endpoint: url,
+	}
+}

proxy/http/http.go

@@ -0,0 +1,149 @@
+// Package http provides a micro rpc to http proxy
+package http
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"path"
+
+	"github.com/micro/go-micro/config/options"
+	"github.com/micro/go-micro/errors"
+	"github.com/micro/go-micro/proxy"
+	"github.com/micro/go-micro/server"
+)
+
+// Proxy will proxy rpc requests as http POST requests. It is a server.Proxy
+type Proxy struct {
+	options.Options
+
+	// The http backend to call
+	Endpoint string
+
+	// first request
+	first bool
+}
+
+func getMethod(hdr map[string]string) string {
+	switch hdr["Micro-Method"] {
+	case "GET", "HEAD", "POST", "PUT", "DELETE", "CONNECT", "OPTIONS", "TRACE", "PATCH":
+		return hdr["Micro-Method"]
+	default:
+		return "POST"
+	}
+}
+
+func getEndpoint(hdr map[string]string) string {
+	ep := hdr["Micro-Endpoint"]
+	if len(ep) > 0 && ep[0] == '/' {
+		return ep
+	}
+	return ""
+}
+
+// ServeRequest honours the server.Router interface
+func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server.Response) error {
+	if p.Endpoint == "" {
+		p.Endpoint = proxy.DefaultEndpoint
+	}
+
+	for {
+		// get data
+		body, err := req.Read()
+		if err == io.EOF {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+
+		// get the header
+		hdr := req.Header()
+
+		// get method
+		method := getMethod(hdr)
+
+		// get endpoint
+		endpoint := getEndpoint(hdr)
+
+		// set the endpoint
+		if len(endpoint) == 0 {
+			endpoint = p.Endpoint
+		} else {
+			// add endpoint to backend
+			u, err := url.Parse(p.Endpoint)
+			if err != nil {
+				return errors.InternalServerError(req.Service(), err.Error())
+			}
+			u.Path = path.Join(u.Path, endpoint)
+			endpoint = u.String()
+		}
+
+		// send to backend
+		hreq, err := http.NewRequest(method, endpoint, bytes.NewReader(body))
+		if err != nil {
+			return errors.InternalServerError(req.Service(), err.Error())
+		}
+
+		// set the headers
+		for k, v := range hdr {
+			hreq.Header.Set(k, v)
+		}
+
+		// make the call
+		hrsp, err := http.DefaultClient.Do(hreq)
+		if err != nil {
+			return errors.InternalServerError(req.Service(), err.Error())
+		}
+
+		// read body
+		b, err := ioutil.ReadAll(hrsp.Body)
+		hrsp.Body.Close()
+		if err != nil {
+			return errors.InternalServerError(req.Service(), err.Error())
+		}
+
+		// set response headers
+		hdr = map[string]string{}
+		for k, _ := range hrsp.Header {
+			hdr[k] = hrsp.Header.Get(k)
+		}
+		// write the header
+		rsp.WriteHeader(hdr)
+		// write the body
+		err = rsp.Write(b)
+		if err == io.EOF {
+			return nil
+		}
+		if err != nil {
+			return errors.InternalServerError(req.Service(), err.Error())
+		}
+	}
+
+	return nil
+}
+
+// NewSingleHostProxy returns a router which sends requests to a single http backend
+func NewSingleHostProxy(url string) proxy.Proxy {
+	return &Proxy{
+		Endpoint: url,
+	}
+}
+
+// NewProxy returns a new proxy which will route using a http client
+func NewProxy(opts ...options.Option) proxy.Proxy {
+	p := new(Proxy)
+	p.Options = options.NewOptions(opts...)
+	p.Options.Init(options.WithString("http"))
+
+	// get endpoint
+	ep, ok := p.Options.Values().Get("proxy.endpoint")
+	if ok {
+		p.Endpoint = ep.(string)
+	}
+
+	return p
+}

proxy/http/http_test.go

@@ -0,0 +1,93 @@
+package http
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/http"
+	"sync"
+	"testing"
+
+	"github.com/micro/go-micro"
+	"github.com/micro/go-micro/client"
+	"github.com/micro/go-micro/registry/memory"
+	"github.com/micro/go-micro/server"
+)
+
+type testHandler struct{}
+
+func (t *testHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.Write([]byte(`{"hello": "world"}`))
+}
+
+func TestHTTPProxy(t *testing.T) {
+	c, err := net.Listen("tcp", "localhost:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+	addr := c.Addr().String()
+
+	url := fmt.Sprintf("http://%s", addr)
+
+	testCases := []struct {
+		// http endpoint to call e.g /foo/bar
+		httpEp string
+		// rpc endpoint called e.g Foo.Bar
+		rpcEp string
+		// should be an error
+		err bool
+	}{
+		{"/", "Foo.Bar", false},
+		{"/", "Foo.Baz", false},
+		{"/helloworld", "Hello.World", true},
+	}
+
+	// handler
+	http.Handle("/", new(testHandler))
+
+	// new proxy
+	p := NewSingleHostProxy(url)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	// new micro service
+	service := micro.NewService(
+		micro.Context(ctx),
+		micro.Name("foobar"),
+		micro.Registry(memory.NewRegistry()),
+		micro.AfterStart(func() error {
+			wg.Done()
+			return nil
+		}),
+	)
+
+	// set router
+	service.Server().Init(
+		server.WithRouter(p),
+	)
+
+	// run service
+	// server
+	go http.Serve(c, nil)
+	go service.Run()
+
+	// wait till service is started
+	wg.Wait()
+
+	for _, test := range testCases {
+		req := service.Client().NewRequest("foobar", test.rpcEp, map[string]string{"foo": "bar"}, client.WithContentType("application/json"))
+		var rsp map[string]string
+		err := service.Client().Call(ctx, req, &rsp)
+		if err != nil && test.err == false {
+			t.Fatal(err)
+		}
+		if v := rsp["hello"]; v != "world" {
+			t.Fatalf("Expected hello world got %s from %s", v, test.rpcEp)
+		}
+	}
+}

proxy/mucp/mucp.go

@@ -0,0 +1,325 @@
+// Package mucp transparently forwards the incoming request using a go-micro client.
+package mucp
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"strings"
+	"sync"
+
+	"github.com/micro/go-micro/client"
+	"github.com/micro/go-micro/codec"
+	"github.com/micro/go-micro/codec/bytes"
+	"github.com/micro/go-micro/config/options"
+	"github.com/micro/go-micro/proxy"
+	"github.com/micro/go-micro/router"
+	"github.com/micro/go-micro/server"
+)
+
+// Proxy will transparently proxy requests to an endpoint.
+// If no endpoint is specified it will call a service using the client.
+type Proxy struct {
+	// embed options
+	options.Options
+
+	// Endpoint specifies the fixed service endpoint to call.
+	Endpoint string
+
+	// The client to use for outbound requests
+	Client client.Client
+
+	// The router for routes
+	Router router.Router
+
+	// A fib of routes service:address
+	sync.RWMutex
+	Routes map[string]map[uint64]router.Route
+
+	// The channel to monitor watcher errors
+	errChan chan error
+}
+
+// read client request and write to server
+func readLoop(r server.Request, s client.Stream) error {
+	// request to backend server
+	req := s.Request()
+
+	for {
+		// get data from client
+		//  no need to decode it
+		body, err := r.Read()
+		if err == io.EOF {
+			return nil
+		}
+
+		if err != nil {
+			return err
+		}
+
+		// get the header from client
+		hdr := r.Header()
+		msg := &codec.Message{
+			Type:   codec.Request,
+			Header: hdr,
+			Body:   body,
+		}
+
+		// write the raw request
+		err = req.Codec().Write(msg, nil)
+		if err == io.EOF {
+			return nil
+		} else if err != nil {
+			return err
+		}
+	}
+}
+
+// toNodes returns a list of node addresses from given routes
+func toNodes(routes map[uint64]router.Route) []string {
+	var nodes []string
+	for _, node := range routes {
+		address := node.Address
+		if len(node.Gateway) > 0 {
+			address = node.Gateway
+		}
+		nodes = append(nodes, address)
+	}
+	return nodes
+}
+
+func (p *Proxy) getRoute(service string) ([]string, error) {
+	// lookup the route cache first
+	p.Lock()
+	routes, ok := p.Routes[service]
+	if ok {
+		p.Unlock()
+		return toNodes(routes), nil
+	}
+	p.Routes[service] = make(map[uint64]router.Route)
+	p.Unlock()
+
+	// if the router is broken return error
+	if status := p.Router.Status(); status.Code == router.Error {
+		return nil, status.Error
+	}
+
+	// lookup the routes in the router
+	results, err := p.Router.Lookup(router.NewQuery(router.QueryService(service)))
+	if err != nil {
+		return nil, err
+	}
+
+	// update the proxy cache
+	p.Lock()
+	for _, route := range results {
+		p.Routes[service][route.Hash()] = route
+	}
+	routes = p.Routes[service]
+	p.Unlock()
+
+	return toNodes(routes), nil
+}
+
+// manageRouteCache applies action on a given route to Proxy route cache
+func (p *Proxy) manageRouteCache(route router.Route, action string) error {
+	switch action {
+	case "create", "update":
+		if _, ok := p.Routes[route.Service]; !ok {
+			p.Routes[route.Service] = make(map[uint64]router.Route)
+		}
+		p.Routes[route.Service][route.Hash()] = route
+	case "delete":
+		if _, ok := p.Routes[route.Service]; !ok {
+			return fmt.Errorf("route not found")
+		}
+		delete(p.Routes[route.Service], route.Hash())
+	default:
+		return fmt.Errorf("unknown action: %s", action)
+	}
+
+	return nil
+}
+
+// watchRoutes watches service routes and updates proxy cache
+func (p *Proxy) watchRoutes() {
+	// this is safe to do as the only way watchRoutes returns is
+	// when some error is written into error channel - we want to bail then
+	defer close(p.errChan)
+
+	// route watcher
+	w, err := p.Router.Watch()
+	if err != nil {
+		p.errChan <- err
+		return
+	}
+
+	for {
+		event, err := w.Next()
+		if err != nil {
+			p.errChan <- err
+			return
+		}
+
+		p.Lock()
+		if err := p.manageRouteCache(event.Route, fmt.Sprintf("%s", event.Type)); err != nil {
+			// TODO: should we bail here?
+			p.Unlock()
+			continue
+		}
+		p.Unlock()
+	}
+}
+
+// ServeRequest honours the server.Router interface
+func (p *Proxy) ServeRequest(ctx context.Context, req server.Request, rsp server.Response) error {
+	// service name
+	service := req.Service()
+	endpoint := req.Endpoint()
+	var addresses []string
+
+	// call a specific backend endpoint either by name or address
+	if len(p.Endpoint) > 0 {
+		// address:port
+		if parts := strings.Split(p.Endpoint, ":"); len(parts) > 1 {
+			addresses = []string{p.Endpoint}
+		} else {
+			// get route for endpoint from router
+			addr, err := p.getRoute(p.Endpoint)
+			if err != nil {
+				return err
+			}
+			// set the address
+			addresses = addr
+			// set the name
+			service = p.Endpoint
+		}
+	} else {
+		// no endpoint was specified just lookup the route
+		// get route for endpoint from router
+		addr, err := p.getRoute(service)
+		if err != nil {
+			return err
+		}
+		addresses = addr
+	}
+
+	var opts []client.CallOption
+
+	// set address if available
+	if len(addresses) > 0 {
+		opts = append(opts, client.WithAddress(addresses...))
+	}
+
+	// read initial request
+	body, err := req.Read()
+	if err != nil {
+		return err
+	}
+
+	// create new request with raw bytes body
+	creq := p.Client.NewRequest(service, endpoint, &bytes.Frame{body}, client.WithContentType(req.ContentType()))
+
+	// create new stream
+	stream, err := p.Client.Stream(ctx, creq, opts...)
+	if err != nil {
+		return err
+	}
+	defer stream.Close()
+
+	// create client request read loop
+	go readLoop(req, stream)
+
+	// get raw response
+	resp := stream.Response()
+
+	// route watcher error
+	var watchErr error
+
+	// create server response write loop
+	for {
+		select {
+		case err := <-p.errChan:
+			if err != nil {
+				watchErr = err
+			}
+			return watchErr
+		default:
+			// read backend response body
+			body, err := resp.Read()
+			if err == io.EOF {
+				return nil
+			} else if err != nil {
+				return err
+			}
+
+			// read backend response header
+			hdr := resp.Header()
+
+			// write raw response header to client
+			rsp.WriteHeader(hdr)
+
+			// write raw response body to client
+			err = rsp.Write(body)
+			if err == io.EOF {
+				return nil
+			} else if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// NewSingleHostProxy returns a proxy which sends requests to a single backend
+func NewSingleHostProxy(endpoint string) *Proxy {
+	return &Proxy{
+		Options:  options.NewOptions(),
+		Endpoint: endpoint,
+	}
+}
+
+// NewProxy returns a new proxy which will route based on mucp headers
+func NewProxy(opts ...options.Option) proxy.Proxy {
+	p := new(Proxy)
+	p.Options = options.NewOptions(opts...)
+	p.Options.Init(options.WithString("mucp"))
+
+	// get endpoint
+	ep, ok := p.Options.Values().Get("proxy.endpoint")
+	if ok {
+		p.Endpoint = ep.(string)
+	}
+
+	// get client
+	c, ok := p.Options.Values().Get("proxy.client")
+	if ok {
+		p.Client = c.(client.Client)
+	}
+
+	// set the default client
+	if p.Client == nil {
+		p.Client = client.DefaultClient
+	}
+
+	// get router
+	r, ok := p.Options.Values().Get("proxy.router")
+	if ok {
+		p.Router = r.(router.Router)
+	}
+
+	// create default router and start it
+	if p.Router == nil {
+		p.Router = router.DefaultRouter
+	}
+
+	// routes cache
+	p.Routes = make(map[string]map[uint64]router.Route)
+
+	// watch router service routes
+	p.errChan = make(chan error, 1)
+	go p.watchRoutes()
+
+	return p
+}

proxy/proxy.go

@@ -0,0 +1,37 @@
+// Package proxy is a transparent proxy built on the go-micro/server
+package proxy
+
+import (
+	"context"
+
+	"github.com/micro/go-micro/client"
+	"github.com/micro/go-micro/config/options"
+	"github.com/micro/go-micro/router"
+	"github.com/micro/go-micro/server"
+)
+
+// Proxy can be used as a proxy server for go-micro services
+type Proxy interface {
+	options.Options
+	// ServeRequest honours the server.Router interface
+	ServeRequest(context.Context, server.Request, server.Response) error
+}
+
+var (
+	DefaultEndpoint = "localhost:9090"
+)
+
+// WithEndpoint sets a proxy endpoint
+func WithEndpoint(e string) options.Option {
+	return options.WithValue("proxy.endpoint", e)
+}
+
+// WithClient sets the client
+func WithClient(c client.Client) options.Option {
+	return options.WithValue("proxy.client", c)
+}
+
+// WithRouter specifies the router to use
+func WithRouter(r router.Router) options.Option {
+	return options.WithValue("proxy.router", r)
+}