598 lines
13 KiB
Go
598 lines
13 KiB
Go
|
package msgbus
|
||
|
|
|
||
|
|
import (
|
||
|
|
"bytes"
|
||
|
|
"context"
|
||
|
|
"encoding/base64"
|
||
|
|
"encoding/json"
|
||
|
|
"fmt"
|
||
|
|
"hash/fnv"
|
||
|
|
"io"
|
||
|
|
"net/http"
|
||
|
|
"strconv"
|
||
|
|
"strings"
|
||
|
|
"time"
|
||
|
|
|
||
|
|
"github.com/gorilla/websocket"
|
||
|
|
"go.opentelemetry.io/otel/metric"
|
||
|
|
"go.uber.org/multierr"
|
||
|
|
|
||
|
|
"go.sour.is/ev"
|
||
|
|
"go.sour.is/ev/event"
|
||
|
|
|
||
|
|
"go.sour.is/pkg/gql"
|
||
|
|
"go.sour.is/pkg/lg"
|
||
|
|
)
|
||
|
|
|
||
|
|
type service struct {
|
||
|
|
es *ev.EventStore
|
||
|
|
|
||
|
|
m_gql_posts metric.Int64Counter
|
||
|
|
m_gql_post_added metric.Int64Counter
|
||
|
|
m_gql_post_added_event metric.Int64Counter
|
||
|
|
m_req_time metric.Int64Histogram
|
||
|
|
}
|
||
|
|
|
||
|
|
type MsgbusResolver interface {
|
||
|
|
Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error)
|
||
|
|
PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *PostEvent, error)
|
||
|
|
IsResolver()
|
||
|
|
}
|
||
|
|
|
||
|
|
func New(ctx context.Context, es *ev.EventStore) (*service, error) {
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
if err := event.Register(ctx, &PostEvent{}); err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
if err := event.RegisterName(ctx, "domain.PostEvent", &PostEvent{}); err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
m := lg.Meter(ctx)
|
||
|
|
|
||
|
|
svc := &service{es: es}
|
||
|
|
|
||
|
|
var err, errs error
|
||
|
|
svc.m_gql_posts, err = m.Int64Counter("msgbus_posts",
|
||
|
|
metric.WithDescription("msgbus graphql posts requests"),
|
||
|
|
)
|
||
|
|
errs = multierr.Append(errs, err)
|
||
|
|
|
||
|
|
svc.m_gql_post_added, err = m.Int64Counter("msgbus_post_added",
|
||
|
|
metric.WithDescription("msgbus graphql post added subcription requests"),
|
||
|
|
)
|
||
|
|
errs = multierr.Append(errs, err)
|
||
|
|
|
||
|
|
svc.m_gql_post_added_event, err = m.Int64Counter("msgbus_post_event",
|
||
|
|
metric.WithDescription("msgbus graphql post added subscription events"),
|
||
|
|
)
|
||
|
|
errs = multierr.Append(errs, err)
|
||
|
|
|
||
|
|
svc.m_req_time, err = m.Int64Histogram("msgbus_request_time",
|
||
|
|
metric.WithDescription("msgbus graphql post added subscription events"),
|
||
|
|
metric.WithUnit("ns"),
|
||
|
|
)
|
||
|
|
errs = multierr.Append(errs, err)
|
||
|
|
|
||
|
|
span.RecordError(err)
|
||
|
|
|
||
|
|
return svc, errs
|
||
|
|
}
|
||
|
|
|
||
|
|
var upgrader = websocket.Upgrader{
|
||
|
|
WriteBufferSize: 4096,
|
||
|
|
CheckOrigin: func(r *http.Request) bool {
|
||
|
|
return true
|
||
|
|
},
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *service) IsResolver() {}
|
||
|
|
func (s *service) RegisterHTTP(mux *http.ServeMux) {
|
||
|
|
mux.Handle("/inbox/", lg.Htrace(http.StripPrefix("/inbox/", s), "inbox"))
|
||
|
|
}
|
||
|
|
func (s *service) ServeHTTP(w http.ResponseWriter, r *http.Request) {
|
||
|
|
ctx := r.Context()
|
||
|
|
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
r = r.WithContext(ctx)
|
||
|
|
|
||
|
|
switch r.Method {
|
||
|
|
case http.MethodGet:
|
||
|
|
if r.Header.Get("Upgrade") == "websocket" {
|
||
|
|
s.websocket(w, r)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
s.get(w, r)
|
||
|
|
case http.MethodPost, http.MethodPut:
|
||
|
|
s.post(w, r)
|
||
|
|
default:
|
||
|
|
w.WriteHeader(http.StatusMethodNotAllowed)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Posts is the resolver for the events field.
|
||
|
|
func (s *service) Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error) {
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
s.m_gql_posts.Add(ctx, 1)
|
||
|
|
|
||
|
|
start := time.Now()
|
||
|
|
defer s.m_req_time.Record(ctx, time.Since(start).Milliseconds())
|
||
|
|
|
||
|
|
streamID := withTag("post-"+name, tag)
|
||
|
|
lis, err := s.es.Read(ctx, streamID, paging.GetIdx(0), paging.GetCount(30))
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
edges := make([]gql.Edge, 0, len(lis))
|
||
|
|
for i := range lis {
|
||
|
|
span.AddEvent(fmt.Sprint("post ", i, " of ", len(lis)))
|
||
|
|
e := lis[i]
|
||
|
|
|
||
|
|
post, ok := e.(*PostEvent)
|
||
|
|
if !ok {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
|
||
|
|
edges = append(edges, post)
|
||
|
|
}
|
||
|
|
|
||
|
|
var first, last uint64
|
||
|
|
if first, err = s.es.FirstIndex(ctx, streamID); err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
if last, err = s.es.LastIndex(ctx, streamID); err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
return &gql.Connection{
|
||
|
|
Paging: &gql.PageInfo{
|
||
|
|
Next: lis.Last().EventMeta().Position < last,
|
||
|
|
Prev: lis.First().EventMeta().Position > first,
|
||
|
|
Begin: lis.First().EventMeta().Position,
|
||
|
|
End: lis.Last().EventMeta().Position,
|
||
|
|
},
|
||
|
|
Edges: edges,
|
||
|
|
}, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func (r *service) PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *PostEvent, error) {
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
r.m_gql_post_added.Add(ctx, 1)
|
||
|
|
|
||
|
|
es := r.es.EventStream()
|
||
|
|
if es == nil {
|
||
|
|
return nil, fmt.Errorf("EventStore does not implement streaming")
|
||
|
|
}
|
||
|
|
|
||
|
|
streamID := withTag("post-"+name, tag)
|
||
|
|
|
||
|
|
sub, err := es.Subscribe(ctx, streamID, after)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
ch := make(chan *PostEvent)
|
||
|
|
|
||
|
|
go func() {
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
{
|
||
|
|
ctx, span := lg.Fork(ctx)
|
||
|
|
defer func() {
|
||
|
|
defer span.End()
|
||
|
|
ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
|
||
|
|
defer cancel()
|
||
|
|
err := sub.Close(ctx)
|
||
|
|
span.RecordError(err)
|
||
|
|
}()
|
||
|
|
}
|
||
|
|
|
||
|
|
for <-sub.Recv(ctx) {
|
||
|
|
events, err := sub.Events(ctx)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
break
|
||
|
|
}
|
||
|
|
span.AddEvent(fmt.Sprintf("received %d events", len(events)))
|
||
|
|
r.m_gql_post_added_event.Add(ctx, int64(len(events)))
|
||
|
|
|
||
|
|
for _, e := range events {
|
||
|
|
if p, ok := e.(*PostEvent); ok {
|
||
|
|
select {
|
||
|
|
case ch <- p:
|
||
|
|
continue
|
||
|
|
case <-ctx.Done():
|
||
|
|
return
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}()
|
||
|
|
|
||
|
|
return ch, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func (s *service) get(w http.ResponseWriter, r *http.Request) {
|
||
|
|
ctx := r.Context()
|
||
|
|
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
start := time.Now()
|
||
|
|
defer s.m_req_time.Record(ctx, time.Since(start).Milliseconds())
|
||
|
|
|
||
|
|
name, tag, _ := strings.Cut(r.URL.Path, "/")
|
||
|
|
if name == "" {
|
||
|
|
w.WriteHeader(http.StatusNotFound)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
streamID := withTag("post-"+name, tag)
|
||
|
|
|
||
|
|
var first event.Event = event.NilEvent
|
||
|
|
if lis, err := s.es.Read(ctx, streamID, 0, 1); err == nil && len(lis) > 0 {
|
||
|
|
first = lis[0]
|
||
|
|
}
|
||
|
|
|
||
|
|
var pos, count int64 = 0, ev.AllEvents
|
||
|
|
qry := r.URL.Query()
|
||
|
|
|
||
|
|
if i, err := strconv.ParseInt(qry.Get("index"), 10, 64); err == nil && i > 1 {
|
||
|
|
pos = i - 1
|
||
|
|
}
|
||
|
|
if i, err := strconv.ParseInt(qry.Get("pos"), 10, 64); err == nil {
|
||
|
|
pos = i
|
||
|
|
}
|
||
|
|
if i, err := strconv.ParseInt(qry.Get("n"), 10, 64); err == nil {
|
||
|
|
count = i
|
||
|
|
}
|
||
|
|
|
||
|
|
span.AddEvent(fmt.Sprint("GET topic=", streamID, " idx=", pos, " n=", count))
|
||
|
|
events, err := s.es.Read(ctx, streamID, pos, count)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
w.WriteHeader(http.StatusInternalServerError)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
if strings.Contains(r.Header.Get("Accept"), "application/json") {
|
||
|
|
w.Header().Add("Content-Type", "application/json")
|
||
|
|
|
||
|
|
if err = encodeJSON(w, first, events...); err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
|
||
|
|
w.WriteHeader(http.StatusInternalServerError)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
for i := range events {
|
||
|
|
fmt.Fprintln(w, events[i])
|
||
|
|
}
|
||
|
|
}
|
||
|
|
func (s *service) post(w http.ResponseWriter, r *http.Request) {
|
||
|
|
ctx := r.Context()
|
||
|
|
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
start := time.Now()
|
||
|
|
defer s.m_req_time.Record(ctx, time.Since(start).Milliseconds())
|
||
|
|
|
||
|
|
name, tags, _ := strings.Cut(r.URL.Path, "/")
|
||
|
|
if name == "" {
|
||
|
|
w.WriteHeader(http.StatusNotFound)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
var first event.Event = event.NilEvent
|
||
|
|
if lis, err := s.es.Read(ctx, "post-"+name, 0, 1); err == nil && len(lis) > 0 {
|
||
|
|
first = lis[0]
|
||
|
|
}
|
||
|
|
|
||
|
|
b, err := io.ReadAll(io.LimitReader(r.Body, 64*1024))
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
|
||
|
|
w.WriteHeader(http.StatusBadRequest)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
r.Body.Close()
|
||
|
|
|
||
|
|
if name == "" {
|
||
|
|
w.WriteHeader(http.StatusNotFound)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
events := event.NewEvents(&PostEvent{
|
||
|
|
payload: b,
|
||
|
|
tags: fields(tags),
|
||
|
|
})
|
||
|
|
|
||
|
|
_, err = s.es.Append(ctx, "post-"+name, events)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
|
||
|
|
w.WriteHeader(http.StatusInternalServerError)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
if first == event.NilEvent {
|
||
|
|
first = events.First()
|
||
|
|
}
|
||
|
|
|
||
|
|
m := events.First().EventMeta()
|
||
|
|
span.AddEvent(fmt.Sprint("POST topic=", name, " tags=", tags, " idx=", m.Position, " id=", m.EventID))
|
||
|
|
|
||
|
|
w.WriteHeader(http.StatusAccepted)
|
||
|
|
if strings.Contains(r.Header.Get("Accept"), "application/json") {
|
||
|
|
w.Header().Add("Content-Type", "application/json")
|
||
|
|
if err = encodeJSON(w, first, events...); err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
|
||
|
|
w.WriteHeader(http.StatusInternalServerError)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
return
|
||
|
|
}
|
||
|
|
span.AddEvent("finish response")
|
||
|
|
|
||
|
|
w.Header().Add("Content-Type", "text/plain")
|
||
|
|
fmt.Fprintf(w, "OK %d %s", m.Position, m.EventID)
|
||
|
|
}
|
||
|
|
func (s *service) websocket(w http.ResponseWriter, r *http.Request) {
|
||
|
|
ctx := r.Context()
|
||
|
|
ctx, span := lg.Span(ctx)
|
||
|
|
defer span.End()
|
||
|
|
|
||
|
|
name, tag, _ := strings.Cut(r.URL.Path, "/")
|
||
|
|
if name == "" {
|
||
|
|
w.WriteHeader(http.StatusNotFound)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
streamID := withTag("post-"+name, tag)
|
||
|
|
|
||
|
|
var first event.Event = event.NilEvent
|
||
|
|
if lis, err := s.es.Read(ctx, streamID, 0, 1); err == nil && len(lis) > 0 {
|
||
|
|
first = lis[0]
|
||
|
|
}
|
||
|
|
|
||
|
|
var pos int64 = 0
|
||
|
|
qry := r.URL.Query()
|
||
|
|
|
||
|
|
if i, err := strconv.ParseInt(qry.Get("index"), 10, 64); err == nil && i > 0 {
|
||
|
|
pos = i - 1
|
||
|
|
}
|
||
|
|
|
||
|
|
span.AddEvent(fmt.Sprint("WS topic=", streamID, " idx=", pos))
|
||
|
|
|
||
|
|
c, err := upgrader.Upgrade(w, r, nil)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
defer c.Close()
|
||
|
|
|
||
|
|
ctx, cancel := context.WithCancel(ctx)
|
||
|
|
c.SetCloseHandler(func(code int, text string) error {
|
||
|
|
cancel()
|
||
|
|
return nil
|
||
|
|
})
|
||
|
|
go func() {
|
||
|
|
for {
|
||
|
|
if err := ctx.Err(); err != nil {
|
||
|
|
return
|
||
|
|
}
|
||
|
|
mt, message, err := c.ReadMessage()
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
span.AddEvent(fmt.Sprintf("recv: %d %s", mt, message))
|
||
|
|
}
|
||
|
|
}()
|
||
|
|
|
||
|
|
es := s.es.EventStream()
|
||
|
|
if es == nil {
|
||
|
|
span.AddEvent("EventStore does not implement streaming")
|
||
|
|
w.WriteHeader(http.StatusInternalServerError)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
|
||
|
|
sub, err := es.Subscribe(ctx, streamID, pos)
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
{
|
||
|
|
ctx, span := lg.Fork(ctx)
|
||
|
|
defer func() {
|
||
|
|
defer span.End()
|
||
|
|
ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
|
||
|
|
defer cancel()
|
||
|
|
err := sub.Close(ctx)
|
||
|
|
span.RecordError(err)
|
||
|
|
}()
|
||
|
|
}
|
||
|
|
|
||
|
|
span.AddEvent("start ws")
|
||
|
|
for <-sub.Recv(ctx) {
|
||
|
|
events, err := sub.Events(ctx)
|
||
|
|
if err != nil {
|
||
|
|
break
|
||
|
|
}
|
||
|
|
span.AddEvent(fmt.Sprint("got events ", len(events)))
|
||
|
|
for i := range events {
|
||
|
|
e, ok := events[i].(*PostEvent)
|
||
|
|
if !ok {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
span.AddEvent(fmt.Sprint("send", i, e.String()))
|
||
|
|
|
||
|
|
var b bytes.Buffer
|
||
|
|
if err = encodeJSON(&b, first, e); err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
}
|
||
|
|
|
||
|
|
err = c.WriteMessage(websocket.TextMessage, b.Bytes())
|
||
|
|
if err != nil {
|
||
|
|
span.RecordError(err)
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
type PostEvent struct {
|
||
|
|
payload []byte
|
||
|
|
tags []string
|
||
|
|
|
||
|
|
event.IsEvent
|
||
|
|
}
|
||
|
|
|
||
|
|
func (e *PostEvent) Values() any {
|
||
|
|
if e == nil {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
return struct {
|
||
|
|
Payload []byte `json:"payload"`
|
||
|
|
Tags []string `json:"tags,omitempty"`
|
||
|
|
}{
|
||
|
|
Payload: e.payload,
|
||
|
|
Tags: e.tags,
|
||
|
|
}
|
||
|
|
}
|
||
|
|
func (e *PostEvent) MarshalBinary() ([]byte, error) {
|
||
|
|
j := e.Values()
|
||
|
|
return json.Marshal(&j)
|
||
|
|
}
|
||
|
|
func (e *PostEvent) UnmarshalBinary(b []byte) error {
|
||
|
|
j := struct {
|
||
|
|
Payload []byte
|
||
|
|
Tags []string
|
||
|
|
}{}
|
||
|
|
err := json.Unmarshal(b, &j)
|
||
|
|
e.payload = j.Payload
|
||
|
|
e.tags = j.Tags
|
||
|
|
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
func (e *PostEvent) MarshalJSON() ([]byte, error) { return e.MarshalBinary() }
|
||
|
|
func (e *PostEvent) UnmarshalJSON(b []byte) error { return e.UnmarshalBinary(b) }
|
||
|
|
|
||
|
|
func (e *PostEvent) ID() string { return e.EventMeta().GetEventID() }
|
||
|
|
func (e *PostEvent) Tags() []string { return e.tags }
|
||
|
|
func (e *PostEvent) Payload() string { return string(e.payload) }
|
||
|
|
func (e *PostEvent) PayloadJSON(ctx context.Context) (m map[string]interface{}, err error) {
|
||
|
|
err = json.Unmarshal([]byte(e.payload), &m)
|
||
|
|
return
|
||
|
|
}
|
||
|
|
func (e *PostEvent) Meta() event.Meta { return e.EventMeta() }
|
||
|
|
func (e *PostEvent) IsEdge() {}
|
||
|
|
|
||
|
|
func (e *PostEvent) String() string {
|
||
|
|
var b bytes.Buffer
|
||
|
|
|
||
|
|
b.WriteString(strconv.FormatUint(e.EventMeta().Position, 10))
|
||
|
|
b.WriteRune('\t')
|
||
|
|
|
||
|
|
b.WriteString(e.EventMeta().EventID.String())
|
||
|
|
b.WriteRune('\t')
|
||
|
|
b.WriteString(string(e.payload))
|
||
|
|
if len(e.tags) > 0 {
|
||
|
|
b.WriteRune('\t')
|
||
|
|
b.WriteString(strings.Join(e.tags, ","))
|
||
|
|
}
|
||
|
|
|
||
|
|
return b.String()
|
||
|
|
}
|
||
|
|
|
||
|
|
func fields(s string) []string {
|
||
|
|
if s == "" {
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
return strings.Split(s, ";")
|
||
|
|
}
|
||
|
|
|
||
|
|
func encodeJSON(w io.Writer, first event.Event, events ...event.Event) error {
|
||
|
|
out := make([]struct {
|
||
|
|
ID uint64 `json:"id"`
|
||
|
|
Payload []byte `json:"payload"`
|
||
|
|
Created string `json:"created"`
|
||
|
|
Tags []string `json:"tags"`
|
||
|
|
Topic struct {
|
||
|
|
Name string `json:"name"`
|
||
|
|
TTL uint64 `json:"ttl"`
|
||
|
|
Seq uint64 `json:"seq"`
|
||
|
|
Created string `json:"created"`
|
||
|
|
} `json:"topic"`
|
||
|
|
}, len(events))
|
||
|
|
|
||
|
|
for i := range events {
|
||
|
|
e, ok := events[i].(*PostEvent)
|
||
|
|
if !ok {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
out[i].ID = e.EventMeta().Position
|
||
|
|
out[i].Created = e.EventMeta().Created().Format(time.RFC3339Nano)
|
||
|
|
out[i].Payload = e.payload
|
||
|
|
out[i].Tags = e.tags
|
||
|
|
out[i].Topic.Name = strings.TrimPrefix(e.EventMeta().StreamID, "post-")
|
||
|
|
out[i].Topic.Created = first.EventMeta().Created().Format(time.RFC3339Nano)
|
||
|
|
out[i].Topic.Seq = e.EventMeta().Position
|
||
|
|
}
|
||
|
|
|
||
|
|
if len(out) == 1 {
|
||
|
|
return json.NewEncoder(w).Encode(out[0])
|
||
|
|
}
|
||
|
|
|
||
|
|
return json.NewEncoder(w).Encode(out)
|
||
|
|
}
|
||
|
|
|
||
|
|
func Projector(e event.Event) []event.Event {
|
||
|
|
m := e.EventMeta()
|
||
|
|
streamID := m.StreamID
|
||
|
|
streamPos := m.Position
|
||
|
|
|
||
|
|
switch e := e.(type) {
|
||
|
|
case *PostEvent:
|
||
|
|
lis := make([]event.Event, len(e.tags))
|
||
|
|
for i := range lis {
|
||
|
|
tag := e.tags[i]
|
||
|
|
ne := event.NewPtr(streamID, streamPos)
|
||
|
|
event.SetStreamID(withTag(streamID, tag), ne)
|
||
|
|
lis[i] = ne
|
||
|
|
}
|
||
|
|
|
||
|
|
return lis
|
||
|
|
}
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
func withTag(id, tag string) string {
|
||
|
|
if tag == "" {
|
||
|
|
return id
|
||
|
|
}
|
||
|
|
|
||
|
|
h := fnv.New128a()
|
||
|
|
fmt.Fprint(h, tag)
|
||
|
|
return id + "-" + base64.RawURLEncoding.EncodeToString(h.Sum(nil))
|
||
|
|
}
|