Live removal of issue comments using htmx websocket

go.mod

@@ -93,9 +93,11 @@ require (
 	github.com/microcosm-cc/bluemonday v1.0.26
 	github.com/microsoft/go-mssqldb v1.7.2
 	github.com/minio/minio-go/v7 v7.0.77
+	github.com/mitchellh/mapstructure v1.5.0
 	github.com/msteinert/pam v1.2.0
 	github.com/nektos/act v0.2.63
 	github.com/niklasfasching/go-org v1.7.0
+	github.com/olahol/melody v1.1.4
 	github.com/olivere/elastic/v7 v7.0.32
 	github.com/opencontainers/go-digest v1.0.0
 	github.com/opencontainers/image-spec v1.1.0
@@ -235,11 +237,12 @@ require (
 	github.com/gorilla/handlers v1.5.2 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
+	github.com/gorilla/websocket v1.5.0 // indirect
 	github.com/h2non/parth v0.0.0-20190131123155-b4df798d6542 // indirect
 	github.com/hashicorp/errwrap v1.1.0 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
 	github.com/hashicorp/go-multierror v1.1.1 // indirect
-	github.com/hashicorp/go-retryablehttp v0.7.7 // indirect
+	github.com/hashicorp/go-retryablehttp v0.7.2 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/imdario/mergo v0.3.16 // indirect
 	github.com/jbenet/go-context v0.0.0-20150711004518-d14ea06fba99 // indirect
@@ -259,7 +262,6 @@ require (
 	github.com/miekg/dns v1.1.61 // indirect
 	github.com/minio/md5-simd v1.1.2 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
-	github.com/mitchellh/mapstructure v1.5.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect

go.sum

@@ -472,6 +472,8 @@ github.com/gorilla/securecookie v1.1.2/go.mod h1:NfCASbcHqRSY+3a8tlWJwsQap2VX5pw
 github.com/gorilla/sessions v1.2.0/go.mod h1:dk2InVEVJ0sfLlnXv9EAgkf6ecYs/i80K/zI+bUmuGM=
 github.com/gorilla/sessions v1.3.0 h1:XYlkq7KcpOB2ZhHBPv5WpjMIxrQosiZanfoy1HLZFzg=
 github.com/gorilla/sessions v1.3.0/go.mod h1:ePLdVu+jbEgHH+KWw8I1z2wqd0BAdAQh/8LRvBeoNcQ=
+github.com/gorilla/websocket v1.5.0 h1:PPwGk2jz7EePpoHN/+ClbZu8SPxiqlu12wZP/3sWmnc=
+github.com/gorilla/websocket v1.5.0/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
 github.com/h2non/gock v1.2.0 h1:K6ol8rfrRkUOefooBC8elXoaNGYkpp7y2qcxGG6BzUE=
 github.com/h2non/gock v1.2.0/go.mod h1:tNhoxHYW2W42cYkYb1WqzdbYIieALC99kpYr7rH/BQk=
 github.com/h2non/parth v0.0.0-20190131123155-b4df798d6542 h1:2VTzZjLZBgl62/EtslCrtky5vbi9dd7HrQPQIx6wqiw=
@@ -481,12 +483,13 @@ github.com/hashicorp/errwrap v1.1.0 h1:OxrOeh75EUXMY8TBjag2fzXGZ40LB6IKw45YeGUDY
 github.com/hashicorp/errwrap v1.1.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/go-cleanhttp v0.5.2 h1:035FKYIWjmULyFRBKPs8TBQoi0x6d9G4xc9neXJWAZQ=
 github.com/hashicorp/go-cleanhttp v0.5.2/go.mod h1:kO/YDlP8L1346E6Sodw+PrpBSV4/SoxCXGY6BqNFT48=
-github.com/hashicorp/go-hclog v1.6.3 h1:Qr2kF+eVWjTiYmU7Y31tYlP1h0q/X3Nl3tPGdaB11/k=
-github.com/hashicorp/go-hclog v1.6.3/go.mod h1:W4Qnvbt70Wk/zYJryRzDRU/4r0kIg0PVHBcfoyhpF5M=
+github.com/hashicorp/go-hclog v0.9.2/go.mod h1:5CU+agLiy3J7N7QjHK5d05KxGsuXiQLrjA0H7acj2lQ=
+github.com/hashicorp/go-hclog v1.5.0 h1:bI2ocEMgcVlz55Oj1xZNBsVi900c7II+fWDyV9o+13c=
+github.com/hashicorp/go-hclog v1.5.0/go.mod h1:W4Qnvbt70Wk/zYJryRzDRU/4r0kIg0PVHBcfoyhpF5M=
 github.com/hashicorp/go-multierror v1.1.1 h1:H5DkEtf6CXdFp0N0Em5UCwQpXMWke8IA0+lD48awMYo=
 github.com/hashicorp/go-multierror v1.1.1/go.mod h1:iw975J/qwKPdAO1clOe2L8331t/9/fmwbPZ6JB6eMoM=
-github.com/hashicorp/go-retryablehttp v0.7.7 h1:C8hUCYzor8PIfXHa4UrZkU4VvK8o9ISHxT2Q8+VepXU=
-github.com/hashicorp/go-retryablehttp v0.7.7/go.mod h1:pkQpWZeYWskR+D1tR2O5OcBFOxfA7DoAO6xtkuQnHTk=
+github.com/hashicorp/go-retryablehttp v0.7.2 h1:AcYqCvkpalPnPF2pn0KamgwamS42TqUDDYFRKq/RAd0=
+github.com/hashicorp/go-retryablehttp v0.7.2/go.mod h1:Jy/gPYAdjqffZ/yFGCFV2doI5wjtH1ewM9u8iYVjtX8=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
@@ -650,6 +653,8 @@ github.com/nxadm/tail v1.4.8 h1:nPr65rt6Y5JFSKQO7qToXr7pePgD6Gwiw05lkbyAQTE=
 github.com/nxadm/tail v1.4.8/go.mod h1:+ncqLTQzXmGhMZNUePPaPqPvBxHAIsmXswZKocGu+AU=
 github.com/oklog/ulid v1.3.1 h1:EGfNDEx6MqHz8B3uNV6QAib1UR2Lm97sHi3ocA6ESJ4=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
+github.com/olahol/melody v1.1.4 h1:RQHfKZkQmDxI0+SLZRNBCn4LiXdqxLKRGSkT8Dyoe/E=
+github.com/olahol/melody v1.1.4/go.mod h1:GgkTl6Y7yWj/HtfD48Q5vLKPVoZOH+Qqgfa7CvJgJM4=
 github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
 github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
 github.com/olivere/elastic/v7 v7.0.32 h1:R7CXvbu8Eq+WlsLgxmKVKPox0oOwAE/2T9Si5BnvK6E=

package.json

@@ -28,6 +28,7 @@
     "esbuild-loader": "4.2.2",
     "escape-goat": "4.0.0",
     "fast-glob": "3.3.2",
+    "htmx-ext-ws": "2.0.1",
     "htmx.org": "2.0.3",
     "idiomorph": "0.3.0",
     "jquery": "3.7.1",

routers/web/web.go

@@ -41,6 +41,7 @@ import (
 	"code.gitea.io/gitea/routers/web/user"
 	user_setting "code.gitea.io/gitea/routers/web/user/setting"
 	"code.gitea.io/gitea/routers/web/user/setting/security"
+	"code.gitea.io/gitea/routers/web/websocket"
 	auth_service "code.gitea.io/gitea/services/auth"
 	"code.gitea.io/gitea/services/context"
 	"code.gitea.io/gitea/services/forms"
@@ -546,6 +547,8 @@ func registerRoutes(m *web.Router) {
 
 	m.Any("/user/events", routing.MarkLongPolling, events.Events)
 
+	websocket.Init(m)
+
 	m.Group("/login/oauth", func() {
 		m.Get("/authorize", web.Bind(forms.AuthorizationForm{}), auth.AuthorizeOAuth)
 		m.Post("/grant", web.Bind(forms.GrantApplicationForm{}), auth.GrantApplicationOAuth)

routers/web/websocket/websocket.go

@@ -0,0 +1,22 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package websocket
+
+import (
+	"code.gitea.io/gitea/modules/web"
+	"code.gitea.io/gitea/services/context"
+	"code.gitea.io/gitea/services/websocket"
+)
+
+func Init(r *web.Router) {
+	m := websocket.Init()
+
+	r.Any("/-/ws", func(ctx *context.Context) {
+		err := m.HandleRequest(ctx.Resp, ctx.Req)
+		if err != nil {
+			ctx.ServerError("HandleRequest", err)
+			return
+		}
+	})
+}

services/context/response.go

@@ -4,6 +4,9 @@
 package context
 
 import (
+	"bufio"
+	"errors"
+	"net"
 	"net/http"
 
 	web_types "code.gitea.io/gitea/modules/web/types"
@@ -30,6 +33,14 @@ type Response struct {
 	status         int
 	befores        []func(ResponseWriter)
 	beforeExecuted bool
+	hijacker       http.Hijacker
+}
+
+func (r *Response) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	if r.hijacker == nil {
+		return nil, nil, errors.New("http.Hijacker not implemented by underlying http.ResponseWriter")
+	}
+	return r.hijacker.Hijack()
 }
 
 // Write writes bytes to HTTP endpoint
@@ -95,9 +106,11 @@ func WrapResponseWriter(resp http.ResponseWriter) *Response {
 	if v, ok := resp.(*Response); ok {
 		return v
 	}
+	hijacker, _ := resp.(http.Hijacker)
 	return &Response{
 		ResponseWriter: resp,
 		status:         0,
 		befores:        make([]func(ResponseWriter), 0),
+		hijacker:       hijacker,
 	}
 }

services/pubsub/memory.go

@@ -0,0 +1,65 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pubsub
+
+import (
+	"context"
+	"errors"
+	"sync"
+)
+
+type Memory struct {
+	sync.Mutex
+
+	topics map[string]map[*Subscriber]struct{}
+}
+
+// New creates an in-memory publisher.
+func NewMemory() Broker {
+	return &Memory{
+		topics: make(map[string]map[*Subscriber]struct{}),
+	}
+}
+
+func (p *Memory) Publish(_ context.Context, _topic string, data []byte) error {
+	p.Lock()
+
+	topic, ok := p.topics[_topic]
+	if !ok {
+		p.Unlock()
+		return errors.New("topic not found")
+	}
+
+	for s := range topic {
+		go (*s)(data)
+	}
+	p.Unlock()
+
+	return nil
+}
+
+func (p *Memory) Subscribe(c context.Context, topic string, subscriber Subscriber) {
+	// Subscribe
+	p.Lock()
+	_, ok := p.topics[topic]
+	if !ok {
+		p.topics[topic] = make(map[*Subscriber]struct{})
+	}
+	p.topics[topic][&subscriber] = struct{}{}
+	p.Unlock()
+
+	// Unsubscribe when context is done
+	go func() {
+		// Wait for context to be done
+		<-c.Done()
+
+		// Unsubscribe
+		p.Lock()
+		delete(p.topics[topic], &subscriber)
+		if len(p.topics[topic]) == 0 {
+			delete(p.topics, topic)
+		}
+		p.Unlock()
+	}()
+}

services/pubsub/memory_test.go

@@ -0,0 +1,34 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pubsub
+
+import (
+	"context"
+	"sync"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPubsub(t *testing.T) {
+	var (
+		wg          sync.WaitGroup
+		testTopic   = "hello-world"
+		testMessage = []byte("test")
+	)
+
+	ctx, cancel := context.WithCancelCause(
+		context.Background(),
+	)
+
+	broker := NewMemory()
+	broker.Subscribe(ctx, testTopic, func(message []byte) { assert.Equal(t, testMessage, message); wg.Done() })
+	broker.Subscribe(ctx, testTopic, func(_ []byte) { wg.Done() })
+
+	wg.Add(2)
+	broker.Publish(ctx, testTopic, testMessage)
+
+	wg.Wait()
+	cancel(nil)
+}

services/pubsub/notifier.go

@@ -0,0 +1,56 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pubsub
+
+import (
+	"context"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/json"
+	"code.gitea.io/gitea/modules/log"
+	notify_service "code.gitea.io/gitea/services/notify"
+)
+
+func InitWithNotifier() Broker {
+	broker := NewMemory() // TODO: allow for other pubsub implementations
+	notify_service.RegisterNotifier(newNotifier(broker))
+	return broker
+}
+
+type pubsubNotifier struct {
+	notify_service.NullNotifier
+	broker Broker
+}
+
+// NewNotifier create a new pubsubNotifier notifier
+func newNotifier(broker Broker) notify_service.Notifier {
+	return &pubsubNotifier{
+		broker: broker,
+	}
+}
+
+func (p *pubsubNotifier) DeleteComment(ctx context.Context, doer *user_model.User, c *issues_model.Comment) {
+	data := struct {
+		Function string
+		Comment  *issues_model.Comment
+		Doer     *user_model.User
+	}{
+		Function: "DeleteComment",
+		Comment:  c,
+		Doer:     doer,
+	}
+
+	msg, err := json.Marshal(data)
+	if err != nil {
+		log.Error("Failed to marshal message: %v", err)
+		return
+	}
+
+	err = p.broker.Publish(ctx, "notify", msg)
+	if err != nil {
+		log.Error("Failed to publish message: %v", err)
+		return
+	}
+}

services/pubsub/types.go

@@ -0,0 +1,14 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package pubsub
+
+import "context"
+
+// Subscriber receives published messages.
+type Subscriber func(data []byte)
+
+type Broker interface {
+	Publish(c context.Context, topic string, data []byte) error
+	Subscribe(c context.Context, topic string, subscriber Subscriber)
+}

services/websocket/comment_notifier.go

@@ -0,0 +1,49 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package websocket
+
+import (
+	"context"
+	"fmt"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/models/perm"
+	"code.gitea.io/gitea/models/perm/access"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unit"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/log"
+
+	"github.com/olahol/melody"
+)
+
+func (n *websocketNotifier) filterIssueSessions(ctx context.Context, repo *repo_model.Repository, issue *issues_model.Issue) []*melody.Session {
+	return n.filterSessions(func(s *melody.Session, data *sessionData) bool {
+		// if the user is watching the issue, they will get notifications
+		if !data.isOnURL(fmt.Sprintf("/%s/%s/issues/%d", repo.Owner.Name, repo.Name, issue.Index)) {
+			return false
+		}
+
+		// the user will get notifications if they have access to the repos issues
+		hasAccess, err := access.HasAccessUnit(ctx, data.user, repo, unit.TypeIssues, perm.AccessModeRead)
+		if err != nil {
+			log.Error("Failed to check access: %v", err)
+			return false
+		}
+
+		return hasAccess
+	})
+}
+
+func (n *websocketNotifier) DeleteComment(ctx context.Context, doer *user_model.User, c *issues_model.Comment) {
+	sessions := n.filterIssueSessions(ctx, c.Issue.Repo, c.Issue)
+
+	for _, s := range sessions {
+		msg := fmt.Sprintf(htmxRemoveElement, fmt.Sprintf("#%s", c.HashTag()))
+		err := s.Write([]byte(msg))
+		if err != nil {
+			log.Error("Failed to write to session: %v", err)
+		}
+	}
+}