142 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			142 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Package event provides a handler which publishes an event
 | 
						|
package event
 | 
						|
 | 
						|
import (
 | 
						|
	"encoding/json"
 | 
						|
	"fmt"
 | 
						|
	"net/http"
 | 
						|
	"path"
 | 
						|
	"regexp"
 | 
						|
	"strings"
 | 
						|
	"time"
 | 
						|
 | 
						|
	"github.com/google/uuid"
 | 
						|
	"github.com/micro/go-micro/v2/api/handler"
 | 
						|
	proto "github.com/micro/go-micro/v2/api/proto"
 | 
						|
	"github.com/micro/go-micro/v2/util/ctx"
 | 
						|
	"github.com/oxtoacart/bpool"
 | 
						|
)
 | 
						|
 | 
						|
var (
 | 
						|
	bufferPool = bpool.NewSizedBufferPool(1024, 8)
 | 
						|
)
 | 
						|
 | 
						|
type event struct {
 | 
						|
	opts handler.Options
 | 
						|
}
 | 
						|
 | 
						|
var (
 | 
						|
	Handler   = "event"
 | 
						|
	versionRe = regexp.MustCompilePOSIX("^v[0-9]+$")
 | 
						|
)
 | 
						|
 | 
						|
func eventName(parts []string) string {
 | 
						|
	return strings.Join(parts, ".")
 | 
						|
}
 | 
						|
 | 
						|
func evRoute(ns, p string) (string, string) {
 | 
						|
	p = path.Clean(p)
 | 
						|
	p = strings.TrimPrefix(p, "/")
 | 
						|
 | 
						|
	if len(p) == 0 {
 | 
						|
		return ns, "event"
 | 
						|
	}
 | 
						|
 | 
						|
	parts := strings.Split(p, "/")
 | 
						|
 | 
						|
	// no path
 | 
						|
	if len(parts) == 0 {
 | 
						|
		// topic: namespace
 | 
						|
		// action: event
 | 
						|
		return strings.Trim(ns, "."), "event"
 | 
						|
	}
 | 
						|
 | 
						|
	// Treat /v[0-9]+ as versioning
 | 
						|
	// /v1/foo/bar => topic: v1.foo action: bar
 | 
						|
	if len(parts) >= 2 && versionRe.Match([]byte(parts[0])) {
 | 
						|
		topic := ns + "." + strings.Join(parts[:2], ".")
 | 
						|
		action := eventName(parts[1:])
 | 
						|
		return topic, action
 | 
						|
	}
 | 
						|
 | 
						|
	// /foo => topic: ns.foo action: foo
 | 
						|
	// /foo/bar => topic: ns.foo action: bar
 | 
						|
	topic := ns + "." + strings.Join(parts[:1], ".")
 | 
						|
	action := eventName(parts[1:])
 | 
						|
 | 
						|
	return topic, action
 | 
						|
}
 | 
						|
 | 
						|
func (e *event) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 | 
						|
	bsize := handler.DefaultMaxRecvSize
 | 
						|
	if e.opts.MaxRecvSize > 0 {
 | 
						|
		bsize = e.opts.MaxRecvSize
 | 
						|
	}
 | 
						|
 | 
						|
	r.Body = http.MaxBytesReader(w, r.Body, bsize)
 | 
						|
 | 
						|
	// request to topic:event
 | 
						|
	// create event
 | 
						|
	// publish to topic
 | 
						|
 | 
						|
	topic, action := evRoute(e.opts.Namespace, r.URL.Path)
 | 
						|
 | 
						|
	// create event
 | 
						|
	ev := &proto.Event{
 | 
						|
		Name: action,
 | 
						|
		// TODO: dedupe event
 | 
						|
		Id:        fmt.Sprintf("%s-%s-%s", topic, action, uuid.New().String()),
 | 
						|
		Header:    make(map[string]*proto.Pair),
 | 
						|
		Timestamp: time.Now().Unix(),
 | 
						|
	}
 | 
						|
 | 
						|
	// set headers
 | 
						|
	for key, vals := range r.Header {
 | 
						|
		header, ok := ev.Header[key]
 | 
						|
		if !ok {
 | 
						|
			header = &proto.Pair{
 | 
						|
				Key: key,
 | 
						|
			}
 | 
						|
			ev.Header[key] = header
 | 
						|
		}
 | 
						|
		header.Values = vals
 | 
						|
	}
 | 
						|
 | 
						|
	// set body
 | 
						|
	if r.Method == "GET" {
 | 
						|
		bytes, _ := json.Marshal(r.URL.Query())
 | 
						|
		ev.Data = string(bytes)
 | 
						|
	} else {
 | 
						|
		// Read body
 | 
						|
		buf := bufferPool.Get()
 | 
						|
		defer bufferPool.Put(buf)
 | 
						|
		if _, err := buf.ReadFrom(r.Body); err != nil {
 | 
						|
			http.Error(w, err.Error(), 500)
 | 
						|
			return
 | 
						|
		}
 | 
						|
		ev.Data = buf.String()
 | 
						|
	}
 | 
						|
 | 
						|
	// get client
 | 
						|
	c := e.opts.Client
 | 
						|
 | 
						|
	// create publication
 | 
						|
	p := c.NewMessage(topic, ev)
 | 
						|
 | 
						|
	// publish event
 | 
						|
	if err := c.Publish(ctx.FromRequest(r), p); err != nil {
 | 
						|
		http.Error(w, err.Error(), 500)
 | 
						|
		return
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
func (e *event) String() string {
 | 
						|
	return "event"
 | 
						|
}
 | 
						|
 | 
						|
func NewHandler(opts ...handler.Option) handler.Handler {
 | 
						|
	return &event{
 | 
						|
		opts: handler.NewOptions(opts...),
 | 
						|
	}
 | 
						|
}
 |