feat: create webfinger app

app/webfinger/events.go

@@ -0,0 +1,117 @@
+package webfinger
+
+import (
+	"encoding/json"
+
+	"github.com/sour-is/ev/pkg/es/event"
+)
+
+type SubjectSet struct {
+	Subject    string             `json:"subject"`
+	Aliases    []string           `json:"aliases,omitempty"`
+	Properties map[string]*string `json:"properties,omitempty"`
+
+	eventMeta event.Meta
+}
+
+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)
+}
+func (e *SubjectSet) UnmarshalBinary(b []byte) error {
+	return json.Unmarshal(b, e)
+}
+
+var _ event.Event = (*SubjectSet)(nil)
+
+type SubjectDeleted struct {
+	Subject    string             `json:"subject"`
+
+	eventMeta event.Meta
+}
+
+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)
+}
+func (e *SubjectDeleted) UnmarshalBinary(b []byte) error {
+	return json.Unmarshal(b, e)
+}
+
+var _ event.Event = (*SubjectDeleted)(nil)
+
+type LinkSet struct {
+	Rel        string             `json:"rel"`
+	Type       string             `json:"type,omitempty"`
+	HRef       string             `json:"href,omitempty"`
+	Titles     map[string]string  `json:"titles,omitempty"`
+	Properties map[string]*string `json:"properties,omitempty"`
+
+	eventMeta event.Meta
+}
+
+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)
+}
+func (e *LinkSet) UnmarshalBinary(b []byte) error {
+	return json.Unmarshal(b, e)
+}
+
+var _ event.Event = (*LinkSet)(nil)
+
+type LinkDeleted struct {
+	Rel string `json:"rel"`
+
+	eventMeta event.Meta
+}
+
+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)
+}
+func (e *LinkDeleted) UnmarshalBinary(b []byte) error {
+	return json.Unmarshal(b, e)
+}
+
+var _ event.Event = (*LinkDeleted)(nil)

app/webfinger/jrd.go

@@ -0,0 +1,303 @@
+package webfinger
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"hash/fnv"
+	"sort"
+
+	"github.com/sour-is/ev/pkg/es/event"
+	"github.com/sour-is/ev/pkg/slice"
+)
+
+func StreamID(subject string) string {
+	h := fnv.New128a()
+	h.Write([]byte(subject))
+	return "webfinger." + base64.RawURLEncoding.EncodeToString(h.Sum(nil))
+}
+
+// JRD is a JSON Resource Descriptor, specifying properties and related links
+// for a resource.
+type JRD struct {
+	Subject    string             `json:"subject,omitempty"`
+	Aliases    []string           `json:"aliases,omitempty"`
+	Properties map[string]*string `json:"properties,omitempty"`
+	Links      Links              `json:"links,omitempty"`
+
+	deleted bool
+	event.AggregateRoot
+}
+
+var _ event.Aggregate = (*JRD)(nil)
+
+// Link is a link to a related resource.
+type Link struct {
+	Rel        string             `json:"rel,omitempty"`
+	Type       string             `json:"type,omitempty"`
+	HRef       string             `json:"href,omitempty"`
+	Titles     map[string]string  `json:"titles,omitempty"`
+	Properties map[string]*string `json:"properties,omitempty"`
+}
+
+type Links []*Link
+
+// Len is the number of elements in the collection.
+func (l Links) Len() int {
+	if l == nil {
+		return 0
+	}
+	return len(l)
+}
+
+// Less reports whether the element with index i
+func (l Links) Less(i int, j int) bool {
+	if l[i] == nil || l[j] == nil {
+		return false
+	}
+	return l[i].Rel < l[j].Rel
+}
+
+// Swap swaps the elements with indexes i and j.
+func (l Links) Swap(i int, j int) {
+	if l == nil {
+		return
+	}
+	l[i], l[j] = l[j], l[i]
+}
+
+// ParseJRD parses the JRD using json.Unmarshal.
+func ParseJRD(blob []byte) (*JRD, error) {
+	jrd := JRD{}
+	err := json.Unmarshal(blob, &jrd)
+	if err != nil {
+		return nil, err
+	}
+	return &jrd, nil
+}
+
+// GetLinkByRel returns the first *Link with the specified rel value.
+func (jrd *JRD) GetLinkByRel(rel string) *Link {
+	for _, link := range jrd.Links {
+		if link.Rel == rel {
+			return link
+		}
+	}
+	return nil
+}
+
+// GetProperty Returns the property value as a string.
+// Per spec a property value can be null, empty string is returned in this case.
+func (jrd *JRD) GetProperty(uri string) string {
+	if jrd.Properties[uri] == nil {
+		return ""
+	}
+	return *jrd.Properties[uri]
+}
+
+// GetProperty Returns the property value as a string.
+// Per spec a property value can be null, empty string is returned in this case.
+func (link *Link) GetProperty(uri string) string {
+	if link.Properties[uri] == nil {
+		return ""
+	}
+	return *link.Properties[uri]
+}
+func (link *Link) SetProperty(name string, value *string) {
+	if link.Properties == nil {
+		link.Properties = make(map[string]*string)
+	}
+	link.Properties[name] = value
+}
+
+// ApplyEvent implements event.Aggregate
+func (a *JRD) ApplyEvent(events ...event.Event) {
+	for _, e := range events {
+		switch e := e.(type) {
+		case *SubjectSet:
+			a.Subject = e.Subject
+			a.Aliases = e.Aliases
+			a.Properties = e.Properties
+
+		case *SubjectDeleted:
+			a.deleted = true
+
+			a.Subject = ""
+			a.Aliases = a.Aliases[:0]
+			a.Links = a.Links[:0]
+			a.Properties = map[string]*string{}
+
+		case *LinkSet:
+			link, ok := slice.FindFn(func(l *Link) bool { return l.Rel == e.Rel }, a.Links...)
+			if !ok {
+				link = &Link{}
+				link.Rel = e.Rel
+				a.Links = append(a.Links, link)
+			}
+
+			link.HRef = e.HRef
+			link.Type = e.Type
+			link.Titles = e.Titles
+			link.Properties = e.Properties
+
+		case *LinkDeleted:
+			a.Links = slice.FilterFn(func(link *Link) bool { return link.Rel != e.Rel }, a.Links...)
+		}
+	}
+}
+
+const NSpubkey = "https://sour.is/ns/pub"
+
+func (a *JRD) OnClaims(method, pubkey string, jrd *JRD) error {
+	if a.Version() > 0 {
+		if v, ok := a.Properties[NSpubkey]; ok && v != nil && *v == pubkey {
+			// pubkey matches!
+		} else {
+			return fmt.Errorf("pubkey does not match")
+		}
+		if a.Subject != jrd.Subject {
+			return fmt.Errorf("subject does not match")
+		}
+
+		if method == "DELETE" {
+			event.Raise(a, &SubjectDeleted{Subject: jrd.Subject})
+			return nil
+		}
+	}
+
+	jrd.SetProperty(NSpubkey, &pubkey)
+
+	err := a.OnSubjectSet(jrd.Subject, jrd.Aliases, jrd.Properties)
+	if err != nil {
+		return err
+	}
+
+	sort.Sort(jrd.Links)
+	sort.Sort(a.Links)
+	for _, z := range slice.Align(
+		jrd.Links,
+		a.Links,
+		func(l, r *Link) bool { return l.Rel < r.Rel },
+	) {
+		// Not in new == delete
+		if z.Key == nil {
+			link := *z.Value
+			event.Raise(a, &LinkDeleted{Rel: link.Rel})
+			continue
+		}
+
+		// Not in old == create
+		if z.Value == nil {
+			link := *z.Key
+			event.Raise(a, &LinkSet{
+				Rel:        link.Rel,
+				Type:       link.Type,
+				HRef:       link.HRef,
+				Titles:     link.Titles,
+				Properties: link.Properties,
+			})
+			continue
+		}
+
+		// in both == compare
+		a.OnLinkSet(*z.Key, *z.Value)
+	}
+
+	return nil
+}
+
+func (a *JRD) OnSubjectSet(subject string, aliases []string, props map[string]*string) error {
+	modified := false
+	e := &SubjectSet{
+		Subject:    subject,
+		Aliases:    aliases,
+		Properties: props,
+	}
+
+	if subject != a.Subject {
+		modified = true
+	}
+
+	sort.Strings(aliases)
+	sort.Strings(a.Aliases)
+	for _, z := range slice.Zip(aliases, a.Aliases) {
+		if z.Key != z.Value {
+			modified = true
+			break
+		}
+	}
+
+	for _, z := range slice.Zip(
+		slice.Zip(slice.FromMap(props)),
+		slice.Zip(slice.FromMap(a.Properties)),
+	) {
+		if z.Key != z.Value {
+			modified = true
+			break
+		}
+	}
+
+	if modified {
+		event.Raise(a, e)
+	}
+
+	return nil
+}
+
+func (a *JRD) OnLinkSet(o, n *Link) error {
+	modified := false
+	e := &LinkSet{
+		Rel:        n.Rel,
+		Type:       n.Type,
+		HRef:       n.HRef,
+		Titles:     n.Titles,
+		Properties: n.Properties,
+	}
+
+	if n.Rel != o.Rel {
+		modified = true
+	}
+	if n.Type != o.Type {
+		modified = true
+	}
+	if n.HRef != o.HRef {
+		modified = true
+	}
+
+	for _, z := range slice.Zip(
+		slice.Zip(slice.FromMap(n.Titles)),
+		slice.Zip(slice.FromMap(o.Titles)),
+	) {
+		if z.Key != z.Value {
+			modified = true
+			break
+		}
+	}
+
+	for _, z := range slice.Zip(
+		slice.Zip(slice.FromMap(n.Properties)),
+		slice.Zip(slice.FromMap(o.Properties)),
+	) {
+		if z.Key != z.Value {
+			modified = true
+			break
+		}
+	}
+
+	if modified {
+		event.Raise(a, e)
+	}
+
+	return nil
+}
+
+func (a *JRD) IsDeleted() bool {
+	return a.deleted
+}
+
+func (a *JRD) SetProperty(name string, value *string) {
+	if a.Properties == nil {
+		a.Properties = make(map[string]*string)
+	}
+	a.Properties[name] = value
+}

app/webfinger/jrd_test.go

@@ -0,0 +1,266 @@
+package webfinger_test
+
+import (
+	"context"
+	"crypto/ed25519"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	jwt "github.com/golang-jwt/jwt/v4"
+	"github.com/matryer/is"
+	"go.uber.org/multierr"
+
+	"github.com/sour-is/ev"
+	"github.com/sour-is/ev/app/webfinger"
+	memstore "github.com/sour-is/ev/pkg/es/driver/mem-store"
+	"github.com/sour-is/ev/pkg/es/driver/projecter"
+	"github.com/sour-is/ev/pkg/es/driver/streamer"
+	"github.com/sour-is/ev/pkg/es/event"
+)
+
+func TestParseJRD(t *testing.T) {
+
+	// Adapted from spec http://tools.ietf.org/html/rfc6415#appendix-A
+	blob := `
+        {
+              "subject":"http://blog.example.com/article/id/314",
+              "aliases":[
+                "http://blog.example.com/cool_new_thing",
+                "http://blog.example.com/steve/article/7"],
+              "properties":{
+                "http://blgx.example.net/ns/version":"1.3",
+                "http://blgx.example.net/ns/ext":null
+              },
+              "links":[
+                {
+                  "rel":"author",
+                  "type":"text/html",
+                  "href":"http://blog.example.com/author/steve",
+                  "titles":{
+                    "default":"About the Author",
+                    "en-us":"Author Information"
+                  },
+                  "properties":{
+                    "http://example.com/role":"editor"
+                  }
+                },
+                {
+                  "rel":"author",
+                  "href":"http://example.com/author/john",
+                  "titles":{
+                    "default":"The other author"
+                  }
+                },
+                {
+                  "rel":"copyright"
+                }
+              ]
+            }
+        `
+	obj, err := webfinger.ParseJRD([]byte(blob))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got, want := obj.Subject, "http://blog.example.com/article/id/314"; got != want {
+		t.Errorf("JRD.Subject is %q, want %q", got, want)
+	}
+	if got, want := obj.GetProperty("http://blgx.example.net/ns/version"), "1.3"; got != want {
+		t.Errorf("obj.GetProperty('http://blgx.example.net/ns/version') returned %q, want %q", got, want)
+	}
+	if got, want := obj.GetProperty("http://blgx.example.net/ns/ext"), ""; got != want {
+		t.Errorf("obj.GetProperty('http://blgx.example.net/ns/ext') returned %q, want %q", got, want)
+	}
+	if obj.GetLinkByRel("copyright") == nil {
+		t.Error("obj.GetLinkByRel('copyright') returned nil, want non-nil value")
+	}
+	if got, want := obj.GetLinkByRel("author").Titles["default"], "About the Author"; got != want {
+		t.Errorf("obj.GetLinkByRel('author').Titles['default'] returned %q, want %q", got, want)
+	}
+	if got, want := obj.GetLinkByRel("author").GetProperty("http://example.com/role"), "editor"; got != want {
+		t.Errorf("obj.GetLinkByRel('author').GetProperty('http://example.com/role') returned %q, want %q", got, want)
+	}
+}
+
+func TestEncodeJRD(t *testing.T) {
+	s, err := json.Marshal(&webfinger.JRD{
+		Subject: "test",
+		Properties: map[string]*string{
+			"https://sour.is/ns/prop1": nil,
+		},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(s) != `{"subject":"test","properties":{"https://sour.is/ns/prop1":null}}` {
+		t.Fatal("output does not match")
+	}
+}
+
+//   {                            "properties":{"https://sour.is/ns/pubkey":"kex1d330ama4vnu3vll5dgwjv3k0pcxsccc5k2xy3j8khndggkszsmsq3hl4ru"},"links":[{"rel":"salty:public","type":"application/json+salty","href":"https://ev.sour.is/inbox/01GAEMKXYJ4857JQP1MJGD61Z5","properties":{"pub":"kex1r8zshlvkc787pxvauaq7hd6awa9kmheddxjj9k80qmenyxk6284s50uvpw"}}]}
+//!= {"subject":"acct:me@sour.is","properties":{"https://sour.is/ns/pubkey":"kex1d330ama4vnu3vll5dgwjv3k0pcxsccc5k2xy3j8khndggkszsmsq3hl4ru"},"links":[{"rel":"salty:public","type":"application/json+salty","href":"https://ev.sour.is/inbox/01GAEMKXYJ4857JQP1MJGD61Z5","properties":{"pub":"kex1r8zshlvkc787pxvauaq7hd6awa9kmheddxjj9k80qmenyxk6284s50uvpw"}}]}
+
+func TestApplyEvents(t *testing.T) {
+	is := is.New(t)
+
+	events := event.NewEvents(
+		&webfinger.SubjectSet{
+			Subject: "acct:me@sour.is",
+			Properties: map[string]*string{
+				"https://sour.is/ns/pubkey": ptr("kex1d330ama4vnu3vll5dgwjv3k0pcxsccc5k2xy3j8khndggkszsmsq3hl4ru"),
+			},
+		},
+		&webfinger.LinkSet{
+			Rel:  "salty:public",
+			Type: "application/json+salty",
+		},
+		&webfinger.LinkSet{
+			Rel:  "salty:private",
+			Type: "application/json+salty",
+		},
+		&webfinger.LinkSet{
+			Rel:  "salty:public",
+			Type: "application/json+salty",
+			HRef: "https://ev.sour.is/inbox/01GAEMKXYJ4857JQP1MJGD61Z5",
+			Properties: map[string]*string{
+				"pub": ptr("kex1r8zshlvkc787pxvauaq7hd6awa9kmheddxjj9k80qmenyxk6284s50uvpw"),
+			},
+		},
+		&webfinger.LinkDeleted{
+			Rel: "salty:private",
+		},
+	)
+	event.SetStreamID(webfinger.StreamID("acct:me@sour.is"), events...)
+
+	jrd := &webfinger.JRD{}
+	jrd.ApplyEvent(events...)
+
+	s, err := json.Marshal(jrd)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	is.Equal(string(s), `{"subject":"acct:me@sour.is","properties":{"https://sour.is/ns/pubkey":"kex1d330ama4vnu3vll5dgwjv3k0pcxsccc5k2xy3j8khndggkszsmsq3hl4ru"},"links":[{"rel":"salty:public","type":"application/json+salty","href":"https://ev.sour.is/inbox/01GAEMKXYJ4857JQP1MJGD61Z5","properties":{"pub":"kex1r8zshlvkc787pxvauaq7hd6awa9kmheddxjj9k80qmenyxk6284s50uvpw"}}]}`)
+
+	events = event.NewEvents(
+		&webfinger.SubjectDeleted{},
+	)
+	event.SetStreamID(webfinger.StreamID("acct:me@sour.is"), events...)
+
+	jrd.ApplyEvent(events...)
+
+	s, err = json.Marshal(jrd)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Log(string(s))
+	if string(s) != `{}` {
+		t.Fatal("output does not match")
+	}
+}
+
+func TestCommands(t *testing.T) {
+	is := is.New(t)
+	ctx := context.Background()
+
+	pub, priv, err := ed25519.GenerateKey(nil)
+	is.NoErr(err)
+
+	// fmt.Println(base64.RawURLEncoding.EncodeToString(key))
+	token := jwt.NewWithClaims(jwt.SigningMethodEdDSA, jwt.MapClaims{
+		"sub":     "acct:me@sour.is",
+		"pub":     enc(pub),
+		"aliases": []string{"acct:xuu@sour.is"},
+		"properties": map[string]*string{
+			"https://example.com/ns/asdf": nil,
+		},
+		"links": []map[string]any{{
+			"rel":    "salty:public",
+			"type":   "application/json+salty",
+			"href":   "https://ev.sour.is",
+			"titles": map[string]string{"default": "Jon Lundy"},
+			"properties": map[string]*string{
+				"pub": ptr("kex140fwaena9t0mrgnjeare5zuknmmvl0vc7agqy5yr938vusxfh9ys34vd2p"),
+			},
+		}},
+		"exp": time.Now().Add(30 * time.Second).Unix(),
+	})
+	aToken, err := token.SignedString(priv)
+	is.NoErr(err)
+
+	es, err := ev.Open(ctx, "mem:", streamer.New(ctx), projecter.New(ctx))
+	is.NoErr(err)
+
+	type claims struct {
+		Subject string `json:"sub"`
+		PubKey  string `json:"pub"`
+		*webfinger.JRD
+		jwt.StandardClaims
+	}
+
+	token, err = jwt.ParseWithClaims(
+		aToken,
+		&claims{},
+		func(tok *jwt.Token) (any, error) {
+			c, ok := tok.Claims.(*claims)
+			if !ok {
+				return nil, fmt.Errorf("wrong type of claim")
+			}
+
+			c.JRD.Subject = c.Subject
+			c.StandardClaims.Subject = c.Subject
+
+			pub, err := dec(c.PubKey)
+			return ed25519.PublicKey(pub), err
+		},
+		jwt.WithValidMethods([]string{"EdDSA"}),
+		jwt.WithJSONNumber(),
+	)
+	is.NoErr(err)
+
+	c, ok := token.Claims.(*claims)
+	is.True(ok)
+
+	t.Logf("%#v", c)
+	a, err := ev.Upsert(ctx, es, webfinger.StreamID(c.Subject), func(ctx context.Context, a *webfinger.JRD) error {
+		a.OnClaims("POST", c.PubKey, c.JRD)
+		return nil
+	})
+	is.NoErr(err)
+
+	for _, e := range a.Events(false) {
+		t.Log(e)
+	}
+}
+
+func ptr[T any](v T) *T {
+	return &v
+}
+func enc(b []byte) string {
+	return base64.RawURLEncoding.EncodeToString(b)
+}
+func dec(s string) ([]byte, error) {
+	s = strings.TrimSpace(s)
+	return base64.RawURLEncoding.DecodeString(s)
+}
+
+func TestMain(m *testing.M) {
+	ctx, stop := context.WithCancel(context.Background())
+	defer stop()
+
+	err := multierr.Combine(
+		ev.Init(ctx),
+		event.Init(ctx),
+		memstore.Init(ctx),
+	)
+	if err != nil {
+		fmt.Println(err)
+		return
+	}
+
+	m.Run()
+}

app/webfinger/webfinger.go

@@ -1 +1,187 @@
 package webfinger
+
+import (
+	"context"
+	"crypto/ed25519"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/golang-jwt/jwt/v4"
+	"github.com/sour-is/ev"
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/es/event"
+)
+
+type service struct {
+	es *ev.EventStore
+}
+
+func New(ctx context.Context, es *ev.EventStore) (*service, error) {
+	ctx, span := lg.Span(ctx)
+	defer span.End()
+
+	if err := event.Register(
+		ctx,
+		&SubjectSet{},
+		&SubjectDeleted{},
+		&LinkSet{},
+		&LinkDeleted{},
+	); err != nil {
+		return nil, err
+	}
+	svc := &service{es: es}
+
+	return svc, nil
+}
+
+func (s *service) RegisterHTTP(mux *http.ServeMux) {}
+func (s *service) RegisterWellKnown(mux *http.ServeMux) {
+	mux.Handle("/webfinger", lg.Htrace(s, "webfinger"))
+}
+func (s *service) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	ctx, span := lg.Span(ctx)
+	defer span.End()
+
+	if r.URL.Path != "/webfinger" {
+		w.WriteHeader(http.StatusNotFound)
+		fmt.Fprint(w, http.StatusText(http.StatusNotFound))
+		return
+
+	}
+
+	switch r.Method {
+	case http.MethodPut, http.MethodDelete:
+		if r.ContentLength > 4096 {
+			w.WriteHeader(http.StatusRequestEntityTooLarge)
+			fmt.Fprint(w, http.StatusText(http.StatusRequestEntityTooLarge))
+			span.AddEvent("request too large")
+
+			return
+		}
+		body, err := io.ReadAll(io.LimitReader(r.Body, 4096))
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, http.StatusText(http.StatusInternalServerError))
+			span.RecordError(err)
+
+			return
+		}
+		r.Body.Close()
+
+		type claims struct {
+			Subject string `json:"sub"`
+			PubKey  string `json:"pub"`
+			*JRD
+			jwt.StandardClaims
+		}
+
+		token, err := jwt.ParseWithClaims(
+			string(body),
+			&claims{},
+			func(tok *jwt.Token) (any, error) {
+				c, ok := tok.Claims.(*claims)
+				if !ok {
+					return nil, fmt.Errorf("wrong type of claim")
+				}
+
+				c.JRD.Subject = c.Subject
+				c.StandardClaims.Subject = c.Subject
+
+				pub, err := dec(c.PubKey)
+				return ed25519.PublicKey(pub), err
+			},
+			jwt.WithValidMethods([]string{"EdDSA"}),
+			jwt.WithJSONNumber(),
+		)
+		if err != nil {
+			w.WriteHeader(http.StatusUnprocessableEntity)
+			fmt.Fprint(w, http.StatusText(http.StatusUnprocessableEntity), ": ", err.Error())
+			span.RecordError(err)
+
+			return
+		}
+
+		c, ok := token.Claims.(*claims)
+		if !ok {
+			w.WriteHeader(http.StatusUnprocessableEntity)
+			fmt.Fprint(w, http.StatusText(http.StatusUnprocessableEntity))
+			span.AddEvent("not a claim")
+
+			return
+		}
+
+		a, err := ev.Upsert(ctx, s.es, StreamID(c.Subject), func(ctx context.Context, a *JRD) error {
+			a.OnClaims(r.Method, c.PubKey, c.JRD)
+			return nil
+		})
+
+		if err != nil {
+			w.WriteHeader(http.StatusUnprocessableEntity)
+			fmt.Fprint(w, http.StatusText(http.StatusUnprocessableEntity), ": ", err.Error())
+			span.RecordError(err)
+
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/jrd+json")
+		w.WriteHeader(http.StatusCreated)
+
+		j := json.NewEncoder(w)
+		j.SetIndent("", "  ")
+		err = j.Encode(a)
+		span.RecordError(err)
+
+	case http.MethodGet:
+		resource := r.URL.Query().Get("resource")
+
+		a := &JRD{}
+		a.SetStreamID(StreamID(resource))
+		err := s.es.Load(ctx, a)
+		if err != nil {
+			span.RecordError(err)
+
+			if errors.Is(err, ev.ErrNotFound) {
+				w.WriteHeader(http.StatusNotFound)
+				fmt.Fprint(w, http.StatusText(http.StatusNotFound))
+				return
+			}
+
+			w.WriteHeader(http.StatusInternalServerError)
+			fmt.Fprint(w, http.StatusText(http.StatusInternalServerError))
+			return
+		}
+
+		if a.IsDeleted() {
+			w.WriteHeader(http.StatusGone)
+			fmt.Fprint(w, http.StatusText(http.StatusGone))
+			span.AddEvent("is deleted")
+
+			return
+		}
+
+		w.Header().Set("Content-Type", "application/jrd+json")
+		w.WriteHeader(http.StatusOK)
+
+		j := json.NewEncoder(w)
+		j.SetIndent("", "  ")
+		err = j.Encode(a)
+		span.RecordError(err)
+
+	default:
+		w.Header().Set("Allow", "GET, PUT, DELETE, OPTIONS")
+		w.WriteHeader(http.StatusMethodNotAllowed)
+		fmt.Fprint(w, http.StatusText(http.StatusMethodNotAllowed))
+		span.AddEvent("method not allow: " + r.Method)
+	}
+}
+
+func dec(s string) ([]byte, error) {
+	s = strings.TrimSpace(s)
+	return base64.RawURLEncoding.DecodeString(s)
+}

cmd/ev/app.webfinger.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/sour-is/ev"
+	"github.com/sour-is/ev/app/webfinger"
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/service"
+	"github.com/sour-is/ev/pkg/slice"
+)
+
+var _ = apps.Register(50, func(ctx context.Context, svc *service.Harness) error {
+	ctx, span := lg.Span(ctx)
+	defer span.End()
+
+	span.AddEvent("Enable WebFinger")
+	eventstore, ok := slice.Find[*ev.EventStore](svc.Services...)
+	if !ok {
+		return fmt.Errorf("*es.EventStore not found in services")
+	}
+
+	wf, err := webfinger.New(ctx, eventstore)
+	if err != nil {
+		span.RecordError(err)
+		return err
+	}
+	svc.Add(wf)
+
+	return nil
+})

cmd/webfinger/app.webfinger.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/sour-is/ev"
+	"github.com/sour-is/ev/app/webfinger"
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/service"
+	"github.com/sour-is/ev/pkg/slice"
+)
+
+var _ = apps.Register(50, func(ctx context.Context, svc *service.Harness) error {
+	ctx, span := lg.Span(ctx)
+	defer span.End()
+
+	span.AddEvent("Enable WebFinger")
+	eventstore, ok := slice.Find[*ev.EventStore](svc.Services...)
+	if !ok {
+		return fmt.Errorf("*es.EventStore not found in services")
+	}
+
+	wf, err := webfinger.New(ctx, eventstore)
+	if err != nil {
+		span.RecordError(err)
+		return err
+	}
+	svc.Add(wf)
+
+	return nil
+})

cmd/webfinger/main.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"log"
+	"net/http"
+	"os"
+	"os/signal"
+
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/service"
+)
+
+var apps service.Apps
+var appName, version = service.AppName()
+
+func main() {
+	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, os.Kill)
+	go func() {
+		<-ctx.Done()
+		defer cancel() // restore interrupt function
+	}()
+
+	svc := &service.Harness{}
+
+	ctx, stop := lg.Init(ctx, appName)
+	svc.OnStop(stop)
+	svc.Add(lg.NewHTTP(ctx))
+
+	svc.Setup(ctx, apps.Apps()...)
+
+	// Run application
+	if err := svc.Run(ctx, appName, version); err != nil && !errors.Is(err, http.ErrServerClosed) {
+		log.Fatal(err)
+	}
+}

cmd/webfinger/svc.es.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"context"
+
+	"github.com/sour-is/ev"
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/env"
+	"github.com/sour-is/ev/pkg/es"
+	diskstore "github.com/sour-is/ev/pkg/es/driver/disk-store"
+	memstore "github.com/sour-is/ev/pkg/es/driver/mem-store"
+	"github.com/sour-is/ev/pkg/es/driver/projecter"
+	resolvelinks "github.com/sour-is/ev/pkg/es/driver/resolve-links"
+	"github.com/sour-is/ev/pkg/es/driver/streamer"
+	"github.com/sour-is/ev/pkg/es/event"
+	"github.com/sour-is/ev/pkg/service"
+	"go.uber.org/multierr"
+)
+
+var _ = apps.Register(10, func(ctx context.Context, svc *service.Harness) error {
+	ctx, span := lg.Span(ctx)
+	defer span.End()
+
+	// setup eventstore
+	err := multierr.Combine(
+		ev.Init(ctx),
+		event.Init(ctx),
+		diskstore.Init(ctx),
+		memstore.Init(ctx),
+	)
+	if err != nil {
+		span.RecordError(err)
+		return err
+	}
+
+	eventstore, err := ev.Open(
+		ctx,
+		env.Default("EV_DATA", "mem:"),
+		resolvelinks.New(),
+		streamer.New(ctx),
+		projecter.New(
+			ctx,
+			projecter.DefaultProjection,
+		),
+	)
+	if err != nil {
+		span.RecordError(err)
+		return err
+	}
+	svc.Add(eventstore, &es.EventStore{EventStore: eventstore})
+
+	return nil
+})

cmd/webfinger/svc.http.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"context"
+	"log"
+	"net/http"
+	"strings"
+
+	"github.com/rs/cors"
+	"github.com/sour-is/ev/internal/lg"
+	"github.com/sour-is/ev/pkg/env"
+	"github.com/sour-is/ev/pkg/mux"
+	"github.com/sour-is/ev/pkg/service"
+	"github.com/sour-is/ev/pkg/slice"
+)
+
+var _ = apps.Register(20, func(ctx context.Context, svc *service.Harness) error {
+	s := &http.Server{}
+	svc.Add(s)
+
+	mux := mux.New()
+	s.Handler = cors.AllowAll().Handler(mux)
+
+	// s.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+	// 	log.Println(r.URL.Path)
+	// 	mux.ServeHTTP(w, r)
+	// })
+
+	s.Addr = env.Default("EV_HTTP", ":8080")
+	if strings.HasPrefix(s.Addr, ":") {
+		s.Addr = "[::]" + s.Addr
+	}
+	svc.OnStart(func(ctx context.Context) error {
+		_, span := lg.Span(ctx)
+		defer span.End()
+
+		log.Print("Listen on ", s.Addr)
+		span.AddEvent("begin listen and serve on " + s.Addr)
+
+		mux.Add(slice.FilterType[interface{ RegisterHTTP(*http.ServeMux) }](svc.Services...)...)
+		return s.ListenAndServe()
+	})
+	svc.OnStop(s.Shutdown)
+
+	return nil
+})

ev.go

@@ -164,6 +164,9 @@ func (es *EventStore) Load(ctx context.Context, agg event.Aggregate) error {
 	if err != nil {
 		return err
 	}
+	if len(events) == 0 {
+		return ErrNotFound
+	}
 
 	Mes_load.Add(ctx, events.Count())
 	event.Append(agg, events...)
@@ -395,7 +398,7 @@ func Upsert[A any, T PA[A]](ctx context.Context, es *EventStore, streamID string
 		attribute.String("agg.streamID", streamID),
 	)
 
-	if err = es.Load(ctx, agg); err != nil {
+	if err = es.Load(ctx, agg); err != nil && !errors.Is(err, ErrNotFound) {
 		return
 	}
 

go.mod

@@ -100,6 +100,7 @@ require (
 )
 
 require (
+	github.com/golang-jwt/jwt/v4 v4.4.3
 	github.com/keys-pub/keys v0.1.22
 	github.com/matryer/is v1.4.0
 	github.com/oklog/ulid/v2 v2.1.0

go.sum

@@ -153,6 +153,8 @@ github.com/gobwas/ws v1.0.2 h1:CoAavW/wd/kulfZmSIBt6p24n4j7tHgNVCjsfHVNUbo=
 github.com/gobwas/ws v1.0.2/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
 github.com/godbus/dbus v4.1.0+incompatible/go.mod h1:/YcGZj5zSblfDWMMoOzV4fas9FZnQYTkDnsGvmh2Grw=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
+github.com/golang-jwt/jwt/v4 v4.4.3 h1:Hxl6lhQFj4AnOX6MLrsCb/+7tCj7DxP7VA+2rDIq5AU=
+github.com/golang-jwt/jwt/v4 v4.4.3/go.mod h1:m21LjoU+eqJr34lmDMbreY2eSTRJ1cv77w39/MY0Ch0=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/glog v1.0.0 h1:nfP3RFugxnNRyKgeWd4oI1nYvXpxrx8ck8ZrcizshdQ=
 github.com/golang/glog v1.0.0/go.mod h1:EWib/APOK0SL3dFbYqvxE3UYd8E6s1ouQ7iEp/0LWV4=

pkg/set/set.go

@@ -34,6 +34,22 @@ func (s Set[T]) Delete(items ...T) Set[T] {
 	return s
 }
 
+func (s Set[T]) Equal(e Set[T]) bool {
+	for k := range s {
+		if _, ok := e[k]; !ok{
+			return false
+		}
+	}
+
+	for k := range e {
+		if _, ok := s[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (s Set[T]) String() string {
 	if s == nil {
 		return "set(<nil>)"

pkg/slice/slice.go

@@ -1,5 +1,9 @@
 package slice
 
+import (
+	"github.com/sour-is/ev/pkg/math"
+)
+
 // FilterType returns a subset that matches the type.
 func FilterType[T any](in ...any) []T {
 	lis := make([]T, 0, len(in))
@@ -11,11 +15,25 @@ func FilterType[T any](in ...any) []T {
 	return lis
 }
 
+func FilterFn[T any](fn func(T) bool, in ...T) []T {
+	lis := make([]T, 0, len(in))
+	for _, t := range in {
+		if fn(t) {
+			lis = append(lis, t)
+		}
+	}
+	return lis
+}
+
 // Find returns the first of type found. or false if not found.
 func Find[T any](in ...any) (T, bool) {
 	return First(FilterType[T](in...)...)
 }
 
+func FindFn[T any](fn func(T) bool, in ...T) (T, bool) {
+	return First(FilterFn(fn, in...)...)
+}
+
 // First returns the first element in a slice.
 func First[T any](in ...T) (T, bool) {
 	if len(in) == 0 {
@@ -26,10 +44,101 @@ func First[T any](in ...T) (T, bool) {
 }
 
 // Map applys func to each element s and returns results as slice.
-func Map[T, U any](s []T, f func(T) U) []U {
+func Map[T, U any](f func(T) U) func(...T) []U {
-	r := make([]U, len(s))
+	return func(lis ...T) []U {
-	for i, v := range s {
+		r := make([]U, len(lis))
+		for i, v := range lis {
 			r[i] = f(v)
 		}
 		return r
 	}
+}
+
+func Reduce[T, R any](r R, fn func(T, R, int) R) func(...T) R {
+	return func(lis ...T) R {
+		for i, t := range lis {
+			r = fn(t, r, i)
+		}
+		return r
+	}
+}
+
+type Pair[K comparable, V any] struct {
+	Key   K
+	Value V
+}
+
+func FromMap[K comparable, V any](m map[K]V) (keys []K, values []V) {
+	if m == nil {
+		return nil, nil
+	}
+
+	keys = make([]K, 0, len(m))
+	values = make([]V, 0, len(m))
+
+	for k := range m {
+		keys = append(keys, k)
+	}
+	for _, k := range keys {
+		values = append(values, m[k])
+	}
+
+	return keys, values
+}
+
+func ToMap[K comparable, V any](keys []K, values []V) (m map[K]V) {
+	m = make(map[K]V, len(keys))
+
+	for i := range keys {
+		if len(values) < i {
+			break
+		}
+		m[keys[i]] = values[i]
+	}
+
+	return m
+}
+
+func Zip[K comparable, V any](k []K, v []V) []Pair[K, V] {
+	lis := make([]Pair[K, V], math.Max(len(k), len(v)))
+	for i := range lis {
+		if k != nil && len(k) > i {
+			lis[i].Key = k[i]
+		}
+
+		if v != nil && len(v) > i {
+			lis[i].Value = v[i]
+		}
+	}
+	return lis
+}
+
+func Align[T any](k []T, v []T, less func(T, T) bool) []Pair[*T, *T] {
+	lis := make([]Pair[*T, *T], 0, math.Max(len(k), len(v)))
+
+	var j int
+
+	for i := 0; i < len(k); {
+		if j >= len(v) || less(k[i], v[j]) {
+			lis = append(lis, Pair[*T, *T]{&k[i], nil})
+			i++
+			continue
+		}
+
+		if less(v[j], k[i]) {
+			lis = append(lis, Pair[*T, *T]{nil, &v[j]})
+			j++
+			continue
+		}
+
+		lis = append(lis, Pair[*T, *T]{&k[i], &v[j]})
+		i++
+		j++
+	}
+	for ; j < len(v); j++ {
+		lis = append(lis, Pair[*T, *T]{nil, &v[j]})
+	}
+
+	return lis
+
+}

pkg/slice/slice_test.go

@@ -0,0 +1,54 @@
+package slice_test
+
+import (
+	"testing"
+
+	"github.com/matryer/is"
+	"github.com/sour-is/ev/pkg/slice"
+)
+
+func TestAlign(t *testing.T) {
+	type testCase struct {
+		left, right []string
+		combined    []slice.Pair[*string, *string]
+	}
+
+	tests := []testCase{
+		{
+			left:  []string{"1", "3", "5"},
+			right: []string{"2", "3", "4"},
+			combined: []slice.Pair[*string, *string]{
+				{ptr("1"), nil},
+				{nil, ptr("2")},
+				{ptr("3"), ptr("3")},
+				{nil, ptr("4")},
+				{ptr("5"), nil},
+			},
+		},
+
+		{
+			left: []string{"2", "3", "4"},
+			right:  []string{"1", "3", "5"},
+			combined: []slice.Pair[*string, *string]{
+				{nil, ptr("1")},
+				{ptr("2"), nil},
+				{ptr("3"), ptr("3")},
+				{ptr("4"), nil},
+				{nil, ptr("5")},
+			},
+		},
+
+	}
+
+	is := is.New(t)
+
+	for _, tt := range tests {
+		combined := slice.Align(tt.left, tt.right, func(l, r string) bool { return l < r })
+		is.Equal(len(combined), len(tt.combined))
+		for i := range combined {
+			is.Equal(combined[i], tt.combined[i])
+		}
+	}
+}
+
+func ptr[T any](v T) *T { return &v }