Further consolidate the libraries

api/api.go

@@ -0,0 +1,144 @@
+package api
+
+import (
+	"errors"
+	"regexp"
+	"strings"
+
+	"github.com/micro/go-micro/registry"
+	"github.com/micro/go-micro/server"
+)
+
+// Endpoint is a mapping between an RPC method and HTTP endpoint
+type Endpoint struct {
+	// RPC Method e.g. Greeter.Hello
+	Name string
+	// Description e.g what's this endpoint for
+	Description string
+	// API Handler e.g rpc, proxy
+	Handler string
+	// HTTP Host e.g example.com
+	Host []string
+	// HTTP Methods e.g GET, POST
+	Method []string
+	// HTTP Path e.g /greeter. Expect POSIX regex
+	Path []string
+}
+
+// Service represents an API service
+type Service struct {
+	// Name of service
+	Name string
+	// The endpoint for this service
+	Endpoint *Endpoint
+	// Versions of this service
+	Services []*registry.Service
+}
+
+func strip(s string) string {
+	return strings.TrimSpace(s)
+}
+
+func slice(s string) []string {
+	var sl []string
+
+	for _, p := range strings.Split(s, ",") {
+		if str := strip(p); len(str) > 0 {
+			sl = append(sl, strip(p))
+		}
+	}
+
+	return sl
+}
+
+// Encode encodes an endpoint to endpoint metadata
+func Encode(e *Endpoint) map[string]string {
+	if e == nil {
+		return nil
+	}
+
+	return map[string]string{
+		"endpoint":    e.Name,
+		"description": e.Description,
+		"method":      strings.Join(e.Method, ","),
+		"path":        strings.Join(e.Path, ","),
+		"host":        strings.Join(e.Host, ","),
+		"handler":     e.Handler,
+	}
+}
+
+// Decode decodes endpoint metadata into an endpoint
+func Decode(e map[string]string) *Endpoint {
+	if e == nil {
+		return nil
+	}
+
+	return &Endpoint{
+		Name:        e["endpoint"],
+		Description: e["description"],
+		Method:      slice(e["method"]),
+		Path:        slice(e["path"]),
+		Host:        slice(e["host"]),
+		Handler:     e["handler"],
+	}
+}
+
+// Validate validates an endpoint to guarantee it won't blow up when being served
+func Validate(e *Endpoint) error {
+	if e == nil {
+		return errors.New("endpoint is nil")
+	}
+
+	if len(e.Name) == 0 {
+		return errors.New("name required")
+	}
+
+	for _, p := range e.Path {
+		_, err := regexp.CompilePOSIX(p)
+		if err != nil {
+			return err
+		}
+	}
+
+	if len(e.Handler) == 0 {
+		return errors.New("invalid handler")
+	}
+
+	return nil
+}
+
+/*
+Design ideas
+
+// Gateway is an api gateway interface
+type Gateway interface {
+	// Register a http handler
+	Handle(pattern string, http.Handler)
+	// Register a route
+	RegisterRoute(r Route)
+	// Init initialises the command line.
+	// It also parses further options.
+	Init(...Option) error
+	// Run the gateway
+	Run() error
+}
+
+// NewGateway returns a new api gateway
+func NewGateway() Gateway {
+	return newGateway()
+}
+*/
+
+// WithEndpoint returns a server.HandlerOption with endpoint metadata set
+//
+// Usage:
+//
+// 	proto.RegisterHandler(service.Server(), new(Handler), api.WithEndpoint(
+//		&api.Endpoint{
+//			Name: "Greeter.Hello",
+//			Path: []string{"/greeter"},
+//		},
+//	))
+func WithEndpoint(e *Endpoint) server.HandlerOption {
+	return server.EndpointMetadata(e.Name, Encode(e))
+}