commit e43ffb92a30381a2aa6ea6060b523eeaa6a3d656
Author: Asim Aslam <asim@aslam.me>
Date:   Mon Jun 3 18:44:43 2019 +0100

    Further consolidate the libraries

diff --git a/registry.go b/registry.go
new file mode 100644
index 0000000..368e31d
--- /dev/null
+++ b/registry.go
@@ -0,0 +1,393 @@
+// Package registry provides a dynamic api service router
+package registry
+
+import (
+	"errors"
+	"fmt"
+	"log"
+	"net/http"
+	"regexp"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/micro/go-micro/api"
+	"github.com/micro/go-micro/api/router"
+	"github.com/micro/go-micro/registry"
+	"github.com/micro/go-micro/registry/cache"
+)
+
+// router is the default router
+type registryRouter struct {
+	exit chan bool
+	opts router.Options
+
+	// registry cache
+	rc cache.Cache
+
+	sync.RWMutex
+	eps map[string]*api.Service
+}
+
+func setNamespace(ns, name string) string {
+	ns = strings.TrimSpace(ns)
+	name = strings.TrimSpace(name)
+
+	// no namespace
+	if len(ns) == 0 {
+		return name
+	}
+
+	switch {
+	// has - suffix
+	case strings.HasSuffix(ns, "-"):
+		return strings.Replace(ns+name, ".", "-", -1)
+	// has . suffix
+	case strings.HasSuffix(ns, "."):
+		return ns + name
+	}
+
+	// default join .
+	return strings.Join([]string{ns, name}, ".")
+}
+
+func (r *registryRouter) isClosed() bool {
+	select {
+	case <-r.exit:
+		return true
+	default:
+		return false
+	}
+}
+
+// refresh list of api services
+func (r *registryRouter) refresh() {
+	var attempts int
+
+	for {
+		services, err := r.opts.Registry.ListServices()
+		if err != nil {
+			attempts++
+			log.Println("Error listing endpoints", err)
+			time.Sleep(time.Duration(attempts) * time.Second)
+			continue
+		}
+
+		attempts = 0
+
+		// for each service, get service and store endpoints
+		for _, s := range services {
+			// only get services for this namespace
+			if !strings.HasPrefix(s.Name, r.opts.Namespace) {
+				continue
+			}
+			service, err := r.rc.GetService(s.Name)
+			if err != nil {
+				continue
+			}
+			r.store(service)
+		}
+
+		// refresh list in 10 minutes... cruft
+		select {
+		case <-time.After(time.Minute * 10):
+		case <-r.exit:
+			return
+		}
+	}
+}
+
+// process watch event
+func (r *registryRouter) process(res *registry.Result) {
+	// skip these things
+	if res == nil || res.Service == nil || !strings.HasPrefix(res.Service.Name, r.opts.Namespace) {
+		return
+	}
+
+	// get entry from cache
+	service, err := r.rc.GetService(res.Service.Name)
+	if err != nil {
+		return
+	}
+
+	// update our local endpoints
+	r.store(service)
+}
+
+// store local endpoint cache
+func (r *registryRouter) store(services []*registry.Service) {
+	// endpoints
+	eps := map[string]*api.Service{}
+
+	// services
+	names := map[string]bool{}
+
+	// create a new endpoint mapping
+	for _, service := range services {
+		// set names we need later
+		names[service.Name] = true
+
+		// map per endpoint
+		for _, endpoint := range service.Endpoints {
+			// create a key service:endpoint_name
+			key := fmt.Sprintf("%s:%s", service.Name, endpoint.Name)
+			// decode endpoint
+			end := api.Decode(endpoint.Metadata)
+
+			// if we got nothing skip
+			if err := api.Validate(end); err != nil {
+				continue
+			}
+
+			// try get endpoint
+			ep, ok := eps[key]
+			if !ok {
+				ep = &api.Service{Name: service.Name}
+			}
+
+			// overwrite the endpoint
+			ep.Endpoint = end
+			// append services
+			ep.Services = append(ep.Services, service)
+			// store it
+			eps[key] = ep
+		}
+	}
+
+	r.Lock()
+	defer r.Unlock()
+
+	// delete any existing eps for services we know
+	for key, service := range r.eps {
+		// skip what we don't care about
+		if !names[service.Name] {
+			continue
+		}
+
+		// ok we know this thing
+		// delete delete delete
+		delete(r.eps, key)
+	}
+
+	// now set the eps we have
+	for name, endpoint := range eps {
+		r.eps[name] = endpoint
+	}
+}
+
+// watch for endpoint changes
+func (r *registryRouter) watch() {
+	var attempts int
+
+	for {
+		if r.isClosed() {
+			return
+		}
+
+		// watch for changes
+		w, err := r.opts.Registry.Watch()
+		if err != nil {
+			attempts++
+			log.Println("Error watching endpoints", err)
+			time.Sleep(time.Duration(attempts) * time.Second)
+			continue
+		}
+
+		ch := make(chan bool)
+
+		go func() {
+			select {
+			case <-ch:
+				w.Stop()
+			case <-r.exit:
+				w.Stop()
+			}
+		}()
+
+		// reset if we get here
+		attempts = 0
+
+		for {
+			// process next event
+			res, err := w.Next()
+			if err != nil {
+				log.Println("Error getting next endpoint", err)
+				close(ch)
+				break
+			}
+			r.process(res)
+		}
+	}
+}
+
+func (r *registryRouter) Options() router.Options {
+	return r.opts
+}
+
+func (r *registryRouter) Close() error {
+	select {
+	case <-r.exit:
+		return nil
+	default:
+		close(r.exit)
+		r.rc.Stop()
+	}
+	return nil
+}
+
+func (r *registryRouter) Endpoint(req *http.Request) (*api.Service, error) {
+	if r.isClosed() {
+		return nil, errors.New("router closed")
+	}
+
+	r.RLock()
+	defer r.RUnlock()
+
+	// use the first match
+	// TODO: weighted matching
+	for _, e := range r.eps {
+		ep := e.Endpoint
+
+		// match
+		var pathMatch, hostMatch, methodMatch bool
+
+		// 1. try method GET, POST, PUT, etc
+		// 2. try host example.com, foobar.com, etc
+		// 3. try path /foo/bar, /bar/baz, etc
+
+		// 1. try match method
+		for _, m := range ep.Method {
+			if req.Method == m {
+				methodMatch = true
+				break
+			}
+		}
+
+		// no match on method pass
+		if len(ep.Method) > 0 && !methodMatch {
+			continue
+		}
+
+		// 2. try match host
+		for _, h := range ep.Host {
+			if req.Host == h {
+				hostMatch = true
+				break
+			}
+		}
+
+		// no match on host pass
+		if len(ep.Host) > 0 && !hostMatch {
+			continue
+		}
+
+		// 3. try match paths
+		for _, p := range ep.Path {
+			re, err := regexp.CompilePOSIX(p)
+			if err == nil && re.MatchString(req.URL.Path) {
+				pathMatch = true
+				break
+			}
+		}
+
+		// no match pass
+		if len(ep.Path) > 0 && !pathMatch {
+			continue
+		}
+
+		// TODO: Percentage traffic
+
+		// we got here, so its a match
+		return e, nil
+	}
+
+	// no match
+	return nil, errors.New("not found")
+}
+
+func (r *registryRouter) Route(req *http.Request) (*api.Service, error) {
+	if r.isClosed() {
+		return nil, errors.New("router closed")
+	}
+
+	// try get an endpoint
+	ep, err := r.Endpoint(req)
+	if err == nil {
+		return ep, nil
+	}
+
+	// error not nil
+	// ignore that shit
+	// TODO: don't ignore that shit
+
+	// get the service name
+	rp, err := r.opts.Resolver.Resolve(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// service name
+	name := setNamespace(r.opts.Namespace, rp.Name)
+
+	// get service
+	services, err := r.rc.GetService(name)
+	if err != nil {
+		return nil, err
+	}
+
+	// only use endpoint matching when the meta handler is set aka api.Default
+	switch r.opts.Handler {
+	// rpc handlers
+	case "meta", "api", "rpc":
+		handler := r.opts.Handler
+
+		// set default handler to api
+		if r.opts.Handler == "meta" {
+			handler = "rpc"
+		}
+
+		// construct api service
+		return &api.Service{
+			Name: name,
+			Endpoint: &api.Endpoint{
+				Name:    rp.Method,
+				Handler: handler,
+			},
+			Services: services,
+		}, nil
+	// http handler
+	case "http", "proxy", "web":
+		// construct api service
+		return &api.Service{
+			Name: name,
+			Endpoint: &api.Endpoint{
+				Name:    req.URL.String(),
+				Handler: r.opts.Handler,
+				Host:    []string{req.Host},
+				Method:  []string{req.Method},
+				Path:    []string{req.URL.Path},
+			},
+			Services: services,
+		}, nil
+	}
+
+	return nil, errors.New("unknown handler")
+}
+
+func newRouter(opts ...router.Option) *registryRouter {
+	options := router.NewOptions(opts...)
+	r := &registryRouter{
+		exit: make(chan bool),
+		opts: options,
+		rc:   cache.New(options.Registry),
+		eps:  make(map[string]*api.Service),
+	}
+	go r.watch()
+	go r.refresh()
+	return r
+}
+
+// NewRouter returns the default router
+func NewRouter(opts ...router.Option) router.Router {
+	return newRouter(opts...)
+}
diff --git a/registry_test.go b/registry_test.go
new file mode 100644
index 0000000..b2e9a59
--- /dev/null
+++ b/registry_test.go
@@ -0,0 +1,181 @@
+package registry
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"testing"
+
+	"github.com/micro/go-micro/api"
+)
+
+func TestSetNamespace(t *testing.T) {
+	testCases := []struct {
+		namespace string
+		name      string
+		expected  string
+	}{
+		// default dotted path
+		{
+			"go.micro.api",
+			"foo",
+			"go.micro.api.foo",
+		},
+		// dotted end
+		{
+			"go.micro.api.",
+			"foo",
+			"go.micro.api.foo",
+		},
+		// dashed end
+		{
+			"go-micro-api-",
+			"foo",
+			"go-micro-api-foo",
+		},
+		// no namespace
+		{
+			"",
+			"foo",
+			"foo",
+		},
+		{
+			"go-micro-api-",
+			"v2.foo",
+			"go-micro-api-v2-foo",
+		},
+	}
+
+	for _, test := range testCases {
+		name := setNamespace(test.namespace, test.name)
+		if name != test.expected {
+			t.Fatalf("expected name %s got %s", test.expected, name)
+		}
+	}
+}
+
+func TestRouter(t *testing.T) {
+	r := newRouter()
+
+	compare := func(expect, got []string) bool {
+		// no data to compare, return true
+		if len(expect) == 0 && len(got) == 0 {
+			return true
+		}
+		// no data expected but got some return false
+		if len(expect) == 0 && len(got) > 0 {
+			return false
+		}
+
+		// compare expected with what we got
+		for _, e := range expect {
+			var seen bool
+			for _, g := range got {
+				if e == g {
+					seen = true
+					break
+				}
+			}
+			if !seen {
+				return false
+			}
+		}
+
+		// we're done, return true
+		return true
+	}
+
+	testData := []struct {
+		e *api.Endpoint
+		r *http.Request
+		m bool
+	}{
+		{
+			e: &api.Endpoint{
+				Name:   "Foo.Bar",
+				Host:   []string{"example.com"},
+				Method: []string{"GET"},
+				Path:   []string{"/foo"},
+			},
+			r: &http.Request{
+				Host:   "example.com",
+				Method: "GET",
+				URL: &url.URL{
+					Path: "/foo",
+				},
+			},
+			m: true,
+		},
+		{
+			e: &api.Endpoint{
+				Name:   "Bar.Baz",
+				Host:   []string{"example.com", "foo.com"},
+				Method: []string{"GET", "POST"},
+				Path:   []string{"/foo/bar"},
+			},
+			r: &http.Request{
+				Host:   "foo.com",
+				Method: "POST",
+				URL: &url.URL{
+					Path: "/foo/bar",
+				},
+			},
+			m: true,
+		},
+		{
+			e: &api.Endpoint{
+				Name:   "Test.Cruft",
+				Host:   []string{"example.com", "foo.com"},
+				Method: []string{"GET", "POST"},
+				Path:   []string{"/xyz"},
+			},
+			r: &http.Request{
+				Host:   "fail.com",
+				Method: "DELETE",
+				URL: &url.URL{
+					Path: "/test/fail",
+				},
+			},
+			m: false,
+		},
+	}
+
+	for _, d := range testData {
+		key := fmt.Sprintf("%s:%s", "test.service", d.e.Name)
+		r.eps[key] = &api.Service{
+			Endpoint: d.e,
+		}
+	}
+
+	for _, d := range testData {
+		e, err := r.Endpoint(d.r)
+		if d.m && err != nil {
+			t.Fatalf("expected match, got %v", err)
+		}
+		if !d.m && err == nil {
+			t.Fatal("expected error got match")
+		}
+		// skip testing the non match
+		if !d.m {
+			continue
+		}
+
+		ep := e.Endpoint
+
+		// test the match
+		if d.e.Name != ep.Name {
+			t.Fatalf("expected %v got %v", d.e.Name, ep.Name)
+		}
+		if ok := compare(d.e.Method, ep.Method); !ok {
+			t.Fatalf("expected %v got %v", d.e.Method, ep.Method)
+		}
+		if ok := compare(d.e.Path, ep.Path); !ok {
+			t.Fatalf("expected %v got %v", d.e.Path, ep.Path)
+		}
+		if ok := compare(d.e.Host, ep.Host); !ok {
+			t.Fatalf("expected %v got %v", d.e.Host, ep.Host)
+		}
+
+	}
+
+}