feat: eventMeta -> event.IsEvent

app/gql/resolver.go

@@ -45,13 +45,13 @@ func (*noop) IsResolver() {}
 func (*noop) CreateSaltyUser(ctx context.Context, nick string, pubkey string) (*salty.SaltyUser, error) {
 	panic("not implemented")
 }
-func (*noop) Posts(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error) {
+func (*noop) Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error) {
 	panic("not implemented")
 }
 func (*noop) SaltyUser(ctx context.Context, nick string) (*salty.SaltyUser, error) {
 	panic("not implemented")
 }
-func (*noop) PostAdded(ctx context.Context, streamID string, after int64) (<-chan *msgbus.PostEvent, error) {
+func (*noop) PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *msgbus.PostEvent, error) {
 	panic("not implemented")
 }
 func (*noop) Events(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error) {

app/msgbus/msgbus.graphqls

@@ -1,9 +1,9 @@
 extend type Query {
-    posts(streamID: String! paging: PageInput): Connection!
+    posts(name: String!, tag: String! = "", paging: PageInput): Connection!
 }
 extend type Subscription {
     """after == 0 start from begining, after == -1 start from end"""
-    postAdded(streamID: String! after: Int! = -1): PostEvent
+    postAdded(name: String!, tag: String! = "", after: Int! = -1): PostEvent
 }
 type PostEvent implements Edge @goModel(model: "go.sour.is/ev/app/msgbus.PostEvent") {
     id: ID!

app/msgbus/service.go

@@ -3,8 +3,10 @@ package msgbus
 import (
 	"bytes"
 	"context"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
+	"hash/fnv"
 	"io"
 	"net/http"
 	"strconv"
@@ -33,8 +35,8 @@ type service struct {
 }
 
 type MsgbusResolver interface {
-	Posts(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error)
+	Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error)
-	PostAdded(ctx context.Context, streamID string, after int64) (<-chan *PostEvent, error)
+	PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *PostEvent, error)
 	IsResolver()
 }
 
@@ -115,7 +117,7 @@ func (s *service) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 // Posts is the resolver for the events field.
-func (s *service) Posts(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error) {
+func (s *service) Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error) {
 	ctx, span := lg.Span(ctx)
 	defer span.End()
 
@@ -124,6 +126,7 @@ func (s *service) Posts(ctx context.Context, streamID string, paging *gql.PageIn
 	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)
@@ -164,7 +167,7 @@ func (s *service) Posts(ctx context.Context, streamID string, paging *gql.PageIn
 	}, nil
 }
 
-func (r *service) PostAdded(ctx context.Context, streamID string, after int64) (<-chan *PostEvent, error) {
+func (r *service) PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *PostEvent, error) {
 	ctx, span := lg.Span(ctx)
 	defer span.End()
 
@@ -175,6 +178,8 @@ func (r *service) PostAdded(ctx context.Context, streamID string, after int64) (
 		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)
@@ -232,14 +237,15 @@ func (s *service) get(w http.ResponseWriter, r *http.Request) {
 	start := time.Now()
 	defer s.m_req_time.Record(ctx, time.Since(start).Milliseconds())
 
-	name, _, _ := strings.Cut(r.URL.Path, "/")
+	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, "post-"+name, 0, 1); err == nil && len(lis) > 0 {
+	if lis, err := s.es.Read(ctx, streamID, 0, 1); err == nil && len(lis) > 0 {
 		first = lis[0]
 	}
 
@@ -256,8 +262,8 @@ func (s *service) get(w http.ResponseWriter, r *http.Request) {
 		count = i
 	}
 
-	span.AddEvent(fmt.Sprint("GET topic=", name, " idx=", pos, " n=", count))
+	span.AddEvent(fmt.Sprint("GET topic=", streamID, " idx=", pos, " n=", count))
-	events, err := s.es.Read(ctx, "post-"+name, pos, count)
+	events, err := s.es.Read(ctx, streamID, pos, count)
 	if err != nil {
 		span.RecordError(err)
 		w.WriteHeader(http.StatusInternalServerError)
@@ -356,14 +362,16 @@ func (s *service) websocket(w http.ResponseWriter, r *http.Request) {
 	ctx, span := lg.Span(ctx)
 	defer span.End()
 
-	name, _, _ := strings.Cut(r.URL.Path, "/")
+	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, "post-"+name, 0, 1); err == nil && len(lis) > 0 {
+	if lis, err := s.es.Read(ctx, streamID, 0, 1); err == nil && len(lis) > 0 {
 		first = lis[0]
 	}
 
@@ -374,7 +382,7 @@ func (s *service) websocket(w http.ResponseWriter, r *http.Request) {
 		pos = i - 1
 	}
 
-	span.AddEvent(fmt.Sprint("WS topic=", name, " idx=", pos))
+	span.AddEvent(fmt.Sprint("WS topic=", streamID, " idx=", pos))
 
 	c, err := upgrader.Upgrade(w, r, nil)
 	if err != nil {
@@ -409,7 +417,7 @@ func (s *service) websocket(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	sub, err := es.Subscribe(ctx, "post-"+name, pos)
+	sub, err := es.Subscribe(ctx, streamID, pos)
 	if err != nil {
 		span.RecordError(err)
 		return
@@ -457,21 +465,9 @@ type PostEvent struct {
 	payload []byte
 	tags    []string
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *PostEvent) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *PostEvent) SetEventMeta(eventMeta event.Meta) {
-	if e == nil {
-		return
-	}
-	e.eventMeta = eventMeta
-}
 func (e *PostEvent) Values() any {
 	if e == nil {
 		return nil
@@ -503,25 +499,23 @@ func (e *PostEvent) UnmarshalBinary(b []byte) error {
 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) 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) Meta() event.Meta { return e.EventMeta() }
-func (e *PostEvent) IsEdge()           {}
+func (e *PostEvent) IsEdge()          {}
 
 func (e *PostEvent) String() string {
 	var b bytes.Buffer
 
-	// b.WriteString(e.eventMeta.StreamID)
+	b.WriteString(strconv.FormatUint(e.EventMeta().Position, 10))
-	// b.WriteRune('@')
-	b.WriteString(strconv.FormatUint(e.eventMeta.Position, 10))
 	b.WriteRune('\t')
 
-	b.WriteString(e.eventMeta.EventID.String())
+	b.WriteString(e.EventMeta().EventID.String())
 	b.WriteRune('\t')
 	b.WriteString(string(e.payload))
 	if len(e.tags) > 0 {
@@ -536,7 +530,7 @@ func fields(s string) []string {
 	if s == "" {
 		return nil
 	}
-	return strings.Split(s, "/")
+	return strings.Split(s, ";")
 }
 
 func encodeJSON(w io.Writer, first event.Event, events ...event.Event) error {
@@ -573,3 +567,32 @@ func encodeJSON(w io.Writer, first event.Event, events ...event.Event) error {
 
 	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))
+}

app/peerfinder/ev-info.go

@@ -51,22 +51,11 @@ func (a *Info) OnUpsert() error {
 type VersionChanged struct {
 	ScriptVersion string `json:"script_version"`
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
 var _ event.Event = (*VersionChanged)(nil)
 
-func (e *VersionChanged) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *VersionChanged) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *VersionChanged) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }

app/peerfinder/ev-request.go

@@ -33,7 +33,7 @@ func (a *Request) ApplyEvent(lis ...event.Event) {
 	for _, e := range lis {
 		switch e := e.(type) {
 		case *RequestSubmitted:
-			a.RequestID = e.eventMeta.EventID.String()
+			a.RequestID = e.EventMeta().EventID.String()
 			a.RequestIP = e.RequestIP
 			a.Hidden = e.Hidden
 			a.Created = ulid.Time(e.EventMeta().EventID.Time())
@@ -120,7 +120,7 @@ func (lis ListResponse) Swap(i, j int) {
 }
 
 type RequestSubmitted struct {
-	eventMeta event.Meta
+	event.IsEvent
 
 	RequestIP string `json:"req_ip"`
 	Hidden    bool   `json:"hide,omitempty"`
@@ -154,22 +154,11 @@ func (r *RequestSubmitted) Family() int {
 	}
 }
 func (r *RequestSubmitted) String() string {
-	return fmt.Sprint(r.eventMeta.EventID, r.RequestIP, r.Hidden, r.CreatedString())
+	return fmt.Sprint(r.EventMeta().EventID, r.RequestIP, r.Hidden, r.CreatedString())
 }
 
 var _ event.Event = (*RequestSubmitted)(nil)
 
-func (e *RequestSubmitted) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *RequestSubmitted) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *RequestSubmitted) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }
@@ -204,7 +193,7 @@ func (e *RequestSubmitted) MarshalEnviron() ([]byte, error) {
 }
 
 type ResultSubmitted struct {
-	eventMeta event.Meta
+	event.IsEvent
 
 	RequestID   string  `json:"req_id"`
 	PeerID      string  `json:"peer_id"`
@@ -219,22 +208,11 @@ type ResultSubmitted struct {
 }
 
 func (r *ResultSubmitted) Created() time.Time {
-	return r.eventMeta.Created()
+	return r.EventMeta().Created()
 }
 
 var _ event.Event = (*ResultSubmitted)(nil)
 
-func (e *ResultSubmitted) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *ResultSubmitted) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *ResultSubmitted) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }
@@ -248,22 +226,11 @@ func (e *ResultSubmitted) String() string {
 type RequestTruncated struct {
 	RequestID string
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
 var _ event.Event = (*RequestTruncated)(nil)
 
-func (e *RequestTruncated) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *RequestTruncated) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *RequestTruncated) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }

app/peerfinder/jobs.go

@@ -164,7 +164,7 @@ func (s *service) cleanRequests(ctx context.Context, now time.Time) error {
 		for _, event := range events {
 			switch e := event.(type) {
 			case *RequestSubmitted:
-				if e.eventMeta.ActualPosition < last-maxResults {
+				if e.EventMeta().ActualPosition < last-maxResults {
 					streamIDs = append(streamIDs, e.RequestID())
 				}
 			}

app/salty/salty-user.go

@@ -60,22 +60,11 @@ type UserRegistered struct {
 	Name   string
 	Pubkey *keys.EdX25519PublicKey
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
 var _ event.Event = (*UserRegistered)(nil)
 
-func (e *UserRegistered) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *UserRegistered) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *UserRegistered) MarshalBinary() (text []byte, err error) {
 	var b bytes.Buffer
 	b.WriteString(e.Name)

app/webfinger/events.go

@@ -11,20 +11,9 @@ type SubjectSet struct {
 	Aliases    []string           `json:"aliases,omitempty"`
 	Properties map[string]*string `json:"properties,omitempty"`
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *SubjectSet) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *SubjectSet) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *SubjectSet) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }
@@ -37,20 +26,9 @@ var _ event.Event = (*SubjectSet)(nil)
 type SubjectDeleted struct {
 	Subject string `json:"subject"`
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *SubjectDeleted) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *SubjectDeleted) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *SubjectDeleted) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }
@@ -67,20 +45,9 @@ type LinkSet struct {
 	Titles     map[string]string  `json:"titles,omitempty"`
 	Properties map[string]*string `json:"properties,omitempty"`
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *LinkSet) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *LinkSet) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *LinkSet) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }
@@ -93,20 +60,9 @@ var _ event.Event = (*LinkSet)(nil)
 type LinkDeleted struct {
 	Rel string `json:"rel"`
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *LinkDeleted) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *LinkDeleted) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
 func (e *LinkDeleted) MarshalBinary() (text []byte, err error) {
 	return json.Marshal(e)
 }

cmd/ev/app.msgbus.go

@@ -8,6 +8,7 @@ import (
 	"go.sour.is/ev/app/msgbus"
 	"go.sour.is/ev/internal/lg"
 	"go.sour.is/ev/pkg/service"
+	"go.sour.is/ev/pkg/es/driver/projecter"
 	"go.sour.is/ev/pkg/slice"
 )
 
@@ -20,6 +21,7 @@ var _ = apps.Register(50, func(ctx context.Context, svc *service.Harness) error
 	if !ok {
 		return fmt.Errorf("*es.EventStore not found in services")
 	}
+	eventstore.Option(projecter.New(ctx, msgbus.Projector))
 
 	msgbus, err := msgbus.New(ctx, eventstore)
 	if err != nil {

ev_test.go

@@ -48,21 +48,9 @@ func (a *Thing) OnSetValue(value string) error {
 type ValueSet struct {
 	Value string
 
-	eventMeta event.Meta
+    event.IsEvent
 }
 
-func (e *ValueSet) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *ValueSet) SetEventMeta(eventMeta event.Meta) {
-	if e == nil {
-		return
-	}
-	e.eventMeta = eventMeta
-}
 func (e *ValueSet) MarshalBinary() ([]byte, error) {
 	return json.Marshal(e)
 }

internal/graph/generated/generated.go

@@ -16,13 +16,13 @@ import (
 	"github.com/99designs/gqlgen/graphql"
 	"github.com/99designs/gqlgen/graphql/introspection"
 	"github.com/99designs/gqlgen/plugin/federation/fedruntime"
+	gqlparser "github.com/vektah/gqlparser/v2"
+	"github.com/vektah/gqlparser/v2/ast"
 	"go.sour.is/ev/app/msgbus"
 	"go.sour.is/ev/app/salty"
 	"go.sour.is/ev/pkg/es"
 	"go.sour.is/ev/pkg/es/event"
 	"go.sour.is/ev/pkg/gql"
-	gqlparser "github.com/vektah/gqlparser/v2"
-	"github.com/vektah/gqlparser/v2/ast"
 )
 
 // region    ************************** generated!.gotpl **************************
@@ -99,7 +99,7 @@ type ComplexityRoot struct {
 
 	Query struct {
 		Events             func(childComplexity int, streamID string, paging *gql.PageInput) int
-		Posts              func(childComplexity int, streamID string, paging *gql.PageInput) int
+		Posts              func(childComplexity int, name string, tag string, paging *gql.PageInput) int
 		SaltyUser          func(childComplexity int, nick string) int
 		__resolve__service func(childComplexity int) int
 	}
@@ -112,7 +112,7 @@ type ComplexityRoot struct {
 
 	Subscription struct {
 		EventAdded func(childComplexity int, streamID string, after int64) int
-		PostAdded  func(childComplexity int, streamID string, after int64) int
+		PostAdded  func(childComplexity int, name string, tag string, after int64) int
 	}
 
 	_Service struct {
@@ -126,12 +126,12 @@ type MutationResolver interface {
 }
 type QueryResolver interface {
 	Events(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error)
-	Posts(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error)
+	Posts(ctx context.Context, name string, tag string, paging *gql.PageInput) (*gql.Connection, error)
 	SaltyUser(ctx context.Context, nick string) (*salty.SaltyUser, error)
 }
 type SubscriptionResolver interface {
 	EventAdded(ctx context.Context, streamID string, after int64) (<-chan *es.GQLEvent, error)
-	PostAdded(ctx context.Context, streamID string, after int64) (<-chan *msgbus.PostEvent, error)
+	PostAdded(ctx context.Context, name string, tag string, after int64) (<-chan *msgbus.PostEvent, error)
 }
 
 type executableSchema struct {
@@ -370,7 +370,7 @@ func (e *executableSchema) Complexity(typeName, field string, childComplexity in
 			return 0, false
 		}
 
-		return e.complexity.Query.Posts(childComplexity, args["streamID"].(string), args["paging"].(*gql.PageInput)), true
+		return e.complexity.Query.Posts(childComplexity, args["name"].(string), args["tag"].(string), args["paging"].(*gql.PageInput)), true
 
 	case "Query.saltyUser":
 		if e.complexity.Query.SaltyUser == nil {
@@ -434,7 +434,7 @@ func (e *executableSchema) Complexity(typeName, field string, childComplexity in
 			return 0, false
 		}
 
-		return e.complexity.Subscription.PostAdded(childComplexity, args["streamID"].(string), args["after"].(int64)), true
+		return e.complexity.Subscription.PostAdded(childComplexity, args["name"].(string), args["tag"].(string), args["after"].(int64)), true
 
 	case "_Service.sdl":
 		if e.complexity._Service.SDL == nil {
@@ -609,11 +609,11 @@ directive @goTag(
 #     set(namespace: String! key: String! value: String): Bool!
 # }`, BuiltIn: false},
 	{Name: "../../../app/msgbus/msgbus.graphqls", Input: `extend type Query {
-    posts(streamID: String! paging: PageInput): Connection!
+    posts(name: String!, tag: String! = "", paging: PageInput): Connection!
 }
 extend type Subscription {
     """after == 0 start from begining, after == -1 start from end"""
-    postAdded(streamID: String! after: Int! = -1): PostEvent
+    postAdded(name: String!, tag: String! = "", after: Int! = -1): PostEvent
 }
 type PostEvent implements Edge @goModel(model: "go.sour.is/ev/app/msgbus.PostEvent") {
     id: ID!
@@ -742,7 +742,7 @@ func (ec *executionContext) field_Query_events_args(ctx context.Context, rawArgs
 	var arg1 *gql.PageInput
 	if tmp, ok := rawArgs["paging"]; ok {
 		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("paging"))
-		arg1, err = ec.unmarshalOPageInput2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐPageInput(ctx, tmp)
+		arg1, err = ec.unmarshalOPageInput2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐPageInput(ctx, tmp)
 		if err != nil {
 			return nil, err
 		}
@@ -755,23 +755,32 @@ func (ec *executionContext) field_Query_posts_args(ctx context.Context, rawArgs
 	var err error
 	args := map[string]interface{}{}
 	var arg0 string
-	if tmp, ok := rawArgs["streamID"]; ok {
+	if tmp, ok := rawArgs["name"]; ok {
-		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("streamID"))
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("name"))
 		arg0, err = ec.unmarshalNString2string(ctx, tmp)
 		if err != nil {
 			return nil, err
 		}
 	}
-	args["streamID"] = arg0
+	args["name"] = arg0
-	var arg1 *gql.PageInput
+	var arg1 string
-	if tmp, ok := rawArgs["paging"]; ok {
+	if tmp, ok := rawArgs["tag"]; ok {
-		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("paging"))
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("tag"))
-		arg1, err = ec.unmarshalOPageInput2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐPageInput(ctx, tmp)
+		arg1, err = ec.unmarshalNString2string(ctx, tmp)
 		if err != nil {
 			return nil, err
 		}
 	}
-	args["paging"] = arg1
+	args["tag"] = arg1
+	var arg2 *gql.PageInput
+	if tmp, ok := rawArgs["paging"]; ok {
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("paging"))
+		arg2, err = ec.unmarshalOPageInput2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐPageInput(ctx, tmp)
+		if err != nil {
+			return nil, err
+		}
+	}
+	args["paging"] = arg2
 	return args, nil
 }
 
@@ -818,23 +827,32 @@ func (ec *executionContext) field_Subscription_postAdded_args(ctx context.Contex
 	var err error
 	args := map[string]interface{}{}
 	var arg0 string
-	if tmp, ok := rawArgs["streamID"]; ok {
+	if tmp, ok := rawArgs["name"]; ok {
-		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("streamID"))
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("name"))
 		arg0, err = ec.unmarshalNString2string(ctx, tmp)
 		if err != nil {
 			return nil, err
 		}
 	}
-	args["streamID"] = arg0
+	args["name"] = arg0
-	var arg1 int64
+	var arg1 string
-	if tmp, ok := rawArgs["after"]; ok {
+	if tmp, ok := rawArgs["tag"]; ok {
-		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("after"))
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("tag"))
-		arg1, err = ec.unmarshalNInt2int64(ctx, tmp)
+		arg1, err = ec.unmarshalNString2string(ctx, tmp)
 		if err != nil {
 			return nil, err
 		}
 	}
-	args["after"] = arg1
+	args["tag"] = arg1
+	var arg2 int64
+	if tmp, ok := rawArgs["after"]; ok {
+		ctx := graphql.WithPathContext(ctx, graphql.NewPathWithField("after"))
+		arg2, err = ec.unmarshalNInt2int64(ctx, tmp)
+		if err != nil {
+			return nil, err
+		}
+	}
+	args["after"] = arg2
 	return args, nil
 }
 
@@ -904,7 +922,7 @@ func (ec *executionContext) _Connection_paging(ctx context.Context, field graphq
 	}
 	res := resTmp.(*gql.PageInfo)
 	fc.Result = res
-	return ec.marshalNPageInfo2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐPageInfo(ctx, field.Selections, res)
+	return ec.marshalNPageInfo2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐPageInfo(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Connection_paging(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -958,7 +976,7 @@ func (ec *executionContext) _Connection_edges(ctx context.Context, field graphql
 	}
 	res := resTmp.([]gql.Edge)
 	fc.Result = res
-	return ec.marshalNEdge2ᚕgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐEdgeᚄ(ctx, field.Selections, res)
+	return ec.marshalNEdge2ᚕgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐEdgeᚄ(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Connection_edges(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -1354,7 +1372,7 @@ func (ec *executionContext) _Event_meta(ctx context.Context, field graphql.Colle
 	}
 	res := resTmp.(*event.Meta)
 	fc.Result = res
-	return ec.marshalNMeta2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx, field.Selections, res)
+	return ec.marshalNMeta2ᚖgoᚗsourᚗisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Event_meta(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -1405,7 +1423,7 @@ func (ec *executionContext) _Event_linked(ctx context.Context, field graphql.Col
 	}
 	res := resTmp.(*es.GQLEvent)
 	fc.Result = res
-	return ec.marshalOEvent2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚐGQLEvent(ctx, field.Selections, res)
+	return ec.marshalOEvent2ᚖgoᚗsourᚗisᚋevᚋpkgᚋesᚐGQLEvent(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Event_linked(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -1699,7 +1717,7 @@ func (ec *executionContext) _Mutation_createSaltyUser(ctx context.Context, field
 	}
 	res := resTmp.(*salty.SaltyUser)
 	fc.Result = res
-	return ec.marshalOSaltyUser2ᚖgithubᚗcomᚋsourᚑisᚋevᚋappᚋsaltyᚐSaltyUser(ctx, field.Selections, res)
+	return ec.marshalOSaltyUser2ᚖgoᚗsourᚗisᚋevᚋappᚋsaltyᚐSaltyUser(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Mutation_createSaltyUser(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -2112,9 +2130,9 @@ func (ec *executionContext) _PostEvent_meta(ctx context.Context, field graphql.C
 		}
 		return graphql.Null
 	}
-	res := resTmp.(*event.Meta)
+	res := resTmp.(event.Meta)
 	fc.Result = res
-	return ec.marshalNMeta2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx, field.Selections, res)
+	return ec.marshalNMeta2goᚗsourᚗisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_PostEvent_meta(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -2168,7 +2186,7 @@ func (ec *executionContext) _Query_events(ctx context.Context, field graphql.Col
 	}
 	res := resTmp.(*gql.Connection)
 	fc.Result = res
-	return ec.marshalNConnection2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐConnection(ctx, field.Selections, res)
+	return ec.marshalNConnection2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐConnection(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Query_events(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -2215,7 +2233,7 @@ func (ec *executionContext) _Query_posts(ctx context.Context, field graphql.Coll
 	}()
 	resTmp, err := ec.ResolverMiddleware(ctx, func(rctx context.Context) (interface{}, error) {
 		ctx = rctx // use context from middleware stack in children
-		return ec.resolvers.Query().Posts(rctx, fc.Args["streamID"].(string), fc.Args["paging"].(*gql.PageInput))
+		return ec.resolvers.Query().Posts(rctx, fc.Args["name"].(string), fc.Args["tag"].(string), fc.Args["paging"].(*gql.PageInput))
 	})
 	if err != nil {
 		ec.Error(ctx, err)
@@ -2229,7 +2247,7 @@ func (ec *executionContext) _Query_posts(ctx context.Context, field graphql.Coll
 	}
 	res := resTmp.(*gql.Connection)
 	fc.Result = res
-	return ec.marshalNConnection2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐConnection(ctx, field.Selections, res)
+	return ec.marshalNConnection2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐConnection(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Query_posts(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -2287,7 +2305,7 @@ func (ec *executionContext) _Query_saltyUser(ctx context.Context, field graphql.
 	}
 	res := resTmp.(*salty.SaltyUser)
 	fc.Result = res
-	return ec.marshalOSaltyUser2ᚖgithubᚗcomᚋsourᚑisᚋevᚋappᚋsaltyᚐSaltyUser(ctx, field.Selections, res)
+	return ec.marshalOSaltyUser2ᚖgoᚗsourᚗisᚋevᚋappᚋsaltyᚐSaltyUser(ctx, field.Selections, res)
 }
 
 func (ec *executionContext) fieldContext_Query_saltyUser(ctx context.Context, field graphql.CollectedField) (fc *graphql.FieldContext, err error) {
@@ -2664,7 +2682,7 @@ func (ec *executionContext) _Subscription_eventAdded(ctx context.Context, field
 				w.Write([]byte{'{'})
 				graphql.MarshalString(field.Alias).MarshalGQL(w)
 				w.Write([]byte{':'})
-				ec.marshalOEvent2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚐGQLEvent(ctx, field.Selections, res).MarshalGQL(w)
+				ec.marshalOEvent2ᚖgoᚗsourᚗisᚋevᚋpkgᚋesᚐGQLEvent(ctx, field.Selections, res).MarshalGQL(w)
 				w.Write([]byte{'}'})
 			})
 		case <-ctx.Done():
@@ -2733,7 +2751,7 @@ func (ec *executionContext) _Subscription_postAdded(ctx context.Context, field g
 	}()
 	resTmp, err := ec.ResolverMiddleware(ctx, func(rctx context.Context) (interface{}, error) {
 		ctx = rctx // use context from middleware stack in children
-		return ec.resolvers.Subscription().PostAdded(rctx, fc.Args["streamID"].(string), fc.Args["after"].(int64))
+		return ec.resolvers.Subscription().PostAdded(rctx, fc.Args["name"].(string), fc.Args["tag"].(string), fc.Args["after"].(int64))
 	})
 	if err != nil {
 		ec.Error(ctx, err)
@@ -2752,7 +2770,7 @@ func (ec *executionContext) _Subscription_postAdded(ctx context.Context, field g
 				w.Write([]byte{'{'})
 				graphql.MarshalString(field.Alias).MarshalGQL(w)
 				w.Write([]byte{':'})
-				ec.marshalOPostEvent2ᚖgithubᚗcomᚋsourᚑisᚋevᚋappᚋmsgbusᚐPostEvent(ctx, field.Selections, res).MarshalGQL(w)
+				ec.marshalOPostEvent2ᚖgoᚗsourᚗisᚋevᚋappᚋmsgbusᚐPostEvent(ctx, field.Selections, res).MarshalGQL(w)
 				w.Write([]byte{'}'})
 			})
 		case <-ctx.Done():
@@ -5603,11 +5621,11 @@ func (ec *executionContext) marshalNBoolean2bool(ctx context.Context, sel ast.Se
 	return res
 }
 
-func (ec *executionContext) marshalNConnection2githubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐConnection(ctx context.Context, sel ast.SelectionSet, v gql.Connection) graphql.Marshaler {
+func (ec *executionContext) marshalNConnection2goᚗsourᚗisᚋevᚋpkgᚋgqlᚐConnection(ctx context.Context, sel ast.SelectionSet, v gql.Connection) graphql.Marshaler {
 	return ec._Connection(ctx, sel, &v)
 }
 
-func (ec *executionContext) marshalNConnection2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐConnection(ctx context.Context, sel ast.SelectionSet, v *gql.Connection) graphql.Marshaler {
+func (ec *executionContext) marshalNConnection2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐConnection(ctx context.Context, sel ast.SelectionSet, v *gql.Connection) graphql.Marshaler {
 	if v == nil {
 		if !graphql.HasFieldError(ctx, graphql.GetFieldContext(ctx)) {
 			ec.Errorf(ctx, "the requested element is null which the schema does not allow")
@@ -5617,7 +5635,7 @@ func (ec *executionContext) marshalNConnection2ᚖgithubᚗcomᚋsourᚑisᚋev
 	return ec._Connection(ctx, sel, v)
 }
 
-func (ec *executionContext) marshalNEdge2githubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐEdge(ctx context.Context, sel ast.SelectionSet, v gql.Edge) graphql.Marshaler {
+func (ec *executionContext) marshalNEdge2goᚗsourᚗisᚋevᚋpkgᚋgqlᚐEdge(ctx context.Context, sel ast.SelectionSet, v gql.Edge) graphql.Marshaler {
 	if v == nil {
 		if !graphql.HasFieldError(ctx, graphql.GetFieldContext(ctx)) {
 			ec.Errorf(ctx, "the requested element is null which the schema does not allow")
@@ -5627,7 +5645,7 @@ func (ec *executionContext) marshalNEdge2githubᚗcomᚋsourᚑisᚋevᚋpkgᚋg
 	return ec._Edge(ctx, sel, v)
 }
 
-func (ec *executionContext) marshalNEdge2ᚕgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐEdgeᚄ(ctx context.Context, sel ast.SelectionSet, v []gql.Edge) graphql.Marshaler {
+func (ec *executionContext) marshalNEdge2ᚕgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐEdgeᚄ(ctx context.Context, sel ast.SelectionSet, v []gql.Edge) graphql.Marshaler {
 	ret := make(graphql.Array, len(v))
 	var wg sync.WaitGroup
 	isLen1 := len(v) == 1
@@ -5651,7 +5669,7 @@ func (ec *executionContext) marshalNEdge2ᚕgithubᚗcomᚋsourᚑisᚋevᚋpkg
 			if !isLen1 {
 				defer wg.Done()
 			}
-			ret[i] = ec.marshalNEdge2githubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐEdge(ctx, sel, v[i])
+			ret[i] = ec.marshalNEdge2goᚗsourᚗisᚋevᚋpkgᚋgqlᚐEdge(ctx, sel, v[i])
 		}
 		if isLen1 {
 			f(i)
@@ -5737,7 +5755,11 @@ func (ec *executionContext) marshalNMap2map(ctx context.Context, sel ast.Selecti
 	return res
 }
 
-func (ec *executionContext) marshalNMeta2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx context.Context, sel ast.SelectionSet, v *event.Meta) graphql.Marshaler {
+func (ec *executionContext) marshalNMeta2goᚗsourᚗisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx context.Context, sel ast.SelectionSet, v event.Meta) graphql.Marshaler {
+	return ec._Meta(ctx, sel, &v)
+}
+
+func (ec *executionContext) marshalNMeta2ᚖgoᚗsourᚗisᚋevᚋpkgᚋesᚋeventᚐMeta(ctx context.Context, sel ast.SelectionSet, v *event.Meta) graphql.Marshaler {
 	if v == nil {
 		if !graphql.HasFieldError(ctx, graphql.GetFieldContext(ctx)) {
 			ec.Errorf(ctx, "the requested element is null which the schema does not allow")
@@ -5747,7 +5769,7 @@ func (ec *executionContext) marshalNMeta2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkg
 	return ec._Meta(ctx, sel, v)
 }
 
-func (ec *executionContext) marshalNPageInfo2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐPageInfo(ctx context.Context, sel ast.SelectionSet, v *gql.PageInfo) graphql.Marshaler {
+func (ec *executionContext) marshalNPageInfo2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐPageInfo(ctx context.Context, sel ast.SelectionSet, v *gql.PageInfo) graphql.Marshaler {
 	if v == nil {
 		if !graphql.HasFieldError(ctx, graphql.GetFieldContext(ctx)) {
 			ec.Errorf(ctx, "the requested element is null which the schema does not allow")
@@ -6117,7 +6139,7 @@ func (ec *executionContext) marshalOBoolean2ᚖbool(ctx context.Context, sel ast
 	return res
 }
 
-func (ec *executionContext) marshalOEvent2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋesᚐGQLEvent(ctx context.Context, sel ast.SelectionSet, v *es.GQLEvent) graphql.Marshaler {
+func (ec *executionContext) marshalOEvent2ᚖgoᚗsourᚗisᚋevᚋpkgᚋesᚐGQLEvent(ctx context.Context, sel ast.SelectionSet, v *es.GQLEvent) graphql.Marshaler {
 	if v == nil {
 		return graphql.Null
 	}
@@ -6140,7 +6162,7 @@ func (ec *executionContext) marshalOInt2ᚖint64(ctx context.Context, sel ast.Se
 	return res
 }
 
-func (ec *executionContext) unmarshalOPageInput2ᚖgithubᚗcomᚋsourᚑisᚋevᚋpkgᚋgqlᚐPageInput(ctx context.Context, v interface{}) (*gql.PageInput, error) {
+func (ec *executionContext) unmarshalOPageInput2ᚖgoᚗsourᚗisᚋevᚋpkgᚋgqlᚐPageInput(ctx context.Context, v interface{}) (*gql.PageInput, error) {
 	if v == nil {
 		return nil, nil
 	}
@@ -6148,14 +6170,14 @@ func (ec *executionContext) unmarshalOPageInput2ᚖgithubᚗcomᚋsourᚑisᚋev
 	return &res, graphql.ErrorOnPath(ctx, err)
 }
 
-func (ec *executionContext) marshalOPostEvent2ᚖgithubᚗcomᚋsourᚑisᚋevᚋappᚋmsgbusᚐPostEvent(ctx context.Context, sel ast.SelectionSet, v *msgbus.PostEvent) graphql.Marshaler {
+func (ec *executionContext) marshalOPostEvent2ᚖgoᚗsourᚗisᚋevᚋappᚋmsgbusᚐPostEvent(ctx context.Context, sel ast.SelectionSet, v *msgbus.PostEvent) graphql.Marshaler {
 	if v == nil {
 		return graphql.Null
 	}
 	return ec._PostEvent(ctx, sel, v)
 }
 
-func (ec *executionContext) marshalOSaltyUser2ᚖgithubᚗcomᚋsourᚑisᚋevᚋappᚋsaltyᚐSaltyUser(ctx context.Context, sel ast.SelectionSet, v *salty.SaltyUser) graphql.Marshaler {
+func (ec *executionContext) marshalOSaltyUser2ᚖgoᚗsourᚗisᚋevᚋappᚋsaltyᚐSaltyUser(ctx context.Context, sel ast.SelectionSet, v *salty.SaltyUser) graphql.Marshaler {
 	if v == nil {
 		return graphql.Null
 	}

internal/graph/resolver/resolver.go

@@ -30,7 +30,7 @@ func (r *queryResolver) Events(ctx context.Context, streamID string, paging *gql
 }
 
 // // foo
-func (r *queryResolver) Posts(ctx context.Context, streamID string, paging *gql.PageInput) (*gql.Connection, error) {
+func (r *queryResolver) Posts(ctx context.Context, name, tag string, paging *gql.PageInput) (*gql.Connection, error) {
 	panic("not implemented")
 }
 
@@ -45,7 +45,7 @@ func (r *subscriptionResolver) EventAdded(ctx context.Context, streamID string,
 }
 
 // // foo
-func (r *subscriptionResolver) PostAdded(ctx context.Context, streamID string, after int64) (<-chan *msgbus.PostEvent, error) {
+func (r *subscriptionResolver) PostAdded(ctx context.Context, name, tag string, after int64) (<-chan *msgbus.PostEvent, error) {
 	panic("not implemented")
 }
 

pkg/es/event/aggregate_test.go

@@ -33,24 +33,11 @@ func (a *Agg) ApplyEvent(lis ...event.Event) {
 type ValueApplied struct {
 	Value string
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
 var _ event.Event = (*ValueApplied)(nil)
 
-func (e *ValueApplied) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-
-func (e *ValueApplied) SetEventMeta(m event.Meta) {
-	if e != nil {
-		e.eventMeta = m
-	}
-}
-
 func (e *ValueApplied) MarshalBinary() ([]byte, error) {
 	return json.Marshal(e)
 }

pkg/es/event/events.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"crypto/rand"
 	"encoding"
-	"encoding/json"
 	"fmt"
 	"io"
 	"strconv"
@@ -156,25 +155,23 @@ func Init(ctx context.Context) error {
 }
 
 type nilEvent struct {
+	IsEvent
 }
 
-func (*nilEvent) EventMeta() Meta             { return Meta{} }
-func (*nilEvent) SetEventMeta(eventMeta Meta) {}
-
 var NilEvent = &nilEvent{}
 
 func (e *nilEvent) MarshalBinary() ([]byte, error) {
-	return json.Marshal(e)
+	return nil, nil
 }
 func (e *nilEvent) UnmarshalBinary(b []byte) error {
-	return json.Unmarshal(b, e)
+	return nil
 }
 
 type EventPtr struct {
 	StreamID string `json:"stream_id"`
 	Pos      uint64 `json:"pos"`
 
-	eventMeta Meta
+	IsEvent
 }
 
 var _ Event = (*EventPtr)(nil)
@@ -202,22 +199,6 @@ func (e *EventPtr) UnmarshalBinary(data []byte) error {
 	return err
 }
 
-// EventMeta implements Event
-func (e *EventPtr) EventMeta() Meta {
-	if e == nil {
-		return Meta{}
-	}
-	return e.eventMeta
-}
-
-// SetEventMeta implements Event
-func (e *EventPtr) SetEventMeta(m Meta) {
-	if e == nil {
-		return
-	}
-	e.eventMeta = m
-}
-
 func (e *EventPtr) Values() any {
 	return struct {
 		StreamID string `json:"stream_id"`
@@ -229,26 +210,30 @@ func (e *EventPtr) Values() any {
 }
 
 type FeedTruncated struct {
-	eventMeta Meta
+	IsEvent
-}
-
-// EventMeta implements Event
-func (e *FeedTruncated) EventMeta() Meta {
-	if e == nil {
-		return Meta{}
-	}
-	return e.eventMeta
-}
-
-// SetEventMeta implements Event
-func (e *FeedTruncated) SetEventMeta(m Meta) {
-	if e == nil {
-		return
-	}
-	e.eventMeta = m
 }
 
 func (e *FeedTruncated) Values() any {
 	return struct {
 	}{}
 }
+
+type property[T any] struct {
+	v T
+}
+
+type IsEvent = property[Meta]
+
+func (p *property[T]) EventMeta() T {
+	if p == nil {
+		var t T
+		return t
+	}
+	return p.v
+}
+
+func (p *property[T]) SetEventMeta(x T) {
+	if p != nil {
+		p.v = x
+	}
+}

pkg/es/event/events_test.go

@@ -14,21 +14,9 @@ import (
 type DummyEvent struct {
 	Value string
 
-	eventMeta event.Meta
+	event.IsEvent
 }
 
-func (e *DummyEvent) EventMeta() event.Meta {
-	if e == nil {
-		return event.Meta{}
-	}
-	return e.eventMeta
-}
-func (e *DummyEvent) SetEventMeta(eventMeta event.Meta) {
-	if e == nil {
-		return
-	}
-	e.eventMeta = eventMeta
-}
 func (e *DummyEvent) MarshalBinary() ([]byte, error) {
 	return json.Marshal(e)
 }

pkg/es/event/reflect.go

@@ -25,7 +25,7 @@ type UnknownEvent struct {
 	eventType string
 	values    map[string]json.RawMessage
 
-	eventMeta Meta
+	IsEvent
 }
 
 var _ Event = (*UnknownEvent)(nil)
@@ -48,16 +48,16 @@ func NewUnknownEventFromValues(eventType string, meta Meta, values url.Values) *
 		}
 	}
 
-	return &UnknownEvent{eventType: eventType, eventMeta: meta, values: jsonValues}
+	e := &UnknownEvent{eventType: eventType, values: jsonValues}
+	e.SetEventMeta(meta)
+	return e
 }
 func NewUnknownEventFromRaw(eventType string, meta Meta, values map[string]json.RawMessage) *UnknownEvent {
-	return &UnknownEvent{eventType: eventType, eventMeta: meta, values: values}
+	e := &UnknownEvent{eventType: eventType, values: values}
+	e.SetEventMeta(meta)
+	return e
 }
-func (u UnknownEvent) EventMeta() Meta   { return u.eventMeta }
 func (u UnknownEvent) EventType() string { return u.eventType }
-func (u *UnknownEvent) SetEventMeta(em Meta) {
-	u.eventMeta = em
-}
 func (u *UnknownEvent) UnmarshalBinary(b []byte) error {
 	return json.Unmarshal(b, &u.values)
 }