Mentions

.babelrc

@@ -1,4 +1,12 @@
 {
   "presets": ["@babel/env", "@babel/react", "@babel/preset-typescript"],
-  "plugins": ["@babel/plugin-proposal-class-properties", "macros"]
+  "plugins": [
+    "@babel/plugin-proposal-class-properties",
+    ["macros", {
+      "lingui": {
+        "version": 5
+      }
+    }],
+    "@lingui/babel-plugin-lingui-macro"
+  ]
 }

app/cmd/routes.go

@@ -201,6 +201,7 @@ func routes(r *web.Engine) *web.Engine {
 		membersApi.Post("/api/v1/posts/:number/comments", apiv1.PostComment())
 		membersApi.Put("/api/v1/posts/:number/comments/:id", apiv1.UpdateComment())
 		membersApi.Delete("/api/v1/posts/:number/comments/:id", apiv1.DeleteComment())
+		membersApi.Get("/api/v1/taggable-users", apiv1.ListTaggableUsers())
 		membersApi.Post("/api/v1/posts/:number/votes", apiv1.AddVote())
 		membersApi.Delete("/api/v1/posts/:number/votes", apiv1.RemoveVote())
 		membersApi.Post("/api/v1/posts/:number/votes/toggle", apiv1.ToggleVote())

app/handlers/apiv1/post.go

@@ -1,6 +1,8 @@
 package apiv1
 
 import (
+	"fmt"
+
 	"github.com/getfider/fider/app/actions"
 	"github.com/getfider/fider/app/metrics"
 	"github.com/getfider/fider/app/models/cmd"
@@ -9,6 +11,7 @@ import (
 	"github.com/getfider/fider/app/models/query"
 	"github.com/getfider/fider/app/pkg/bus"
 	"github.com/getfider/fider/app/pkg/env"
+	"github.com/getfider/fider/app/pkg/markdown"
 	"github.com/getfider/fider/app/pkg/web"
 	"github.com/getfider/fider/app/tasks"
 )
@@ -212,6 +215,11 @@ func ListComments() web.HandlerFunc {
 			return c.Failure(err)
 		}
 
+		// the content of the comment needs to be sanitized before it is returned
+		for _, comment := range getComments.Result {
+			comment.Content = markdown.StripMentionMetaData(comment.Content)
+		}
+
 		return c.Ok(getComments.Result)
 	}
 }
@@ -229,6 +237,8 @@ func GetComment() web.HandlerFunc {
 			return c.Failure(err)
 		}
 
+		commentByID.Result.Content = markdown.StripMentionMetaData(commentByID.Result.Content)
+
 		return c.Ok(commentByID.Result)
 	}
 }
@@ -279,13 +289,18 @@ func PostComment() web.HandlerFunc {
 		}
 
 		addNewComment := &cmd.AddNewComment{
-			Post:    getPost.Result,
-			Content: action.Content,
+			Post: getPost.Result,
+			Content: entity.CommentString(action.Content).FormatMentionJson(func(mention entity.Mention) string {
+				return fmt.Sprintf(`{"id":%d,"name":"%s"}`, mention.ID, mention.Name)
+			}),
 		}
 		if err := bus.Dispatch(c, addNewComment); err != nil {
 			return c.Failure(err)
 		}
 
+		// For processing, restore the original content
+		addNewComment.Result.Content = action.Content
+
 		if err := bus.Dispatch(c, &cmd.SetAttachments{
 			Post:        getPost.Result,
 			Comment:     addNewComment.Result,
@@ -294,7 +309,7 @@ func PostComment() web.HandlerFunc {
 			return c.Failure(err)
 		}
 
-		c.Enqueue(tasks.NotifyAboutNewComment(getPost.Result, action.Content))
+		c.Enqueue(tasks.NotifyAboutNewComment(addNewComment.Result, getPost.Result))
 
 		metrics.TotalComments.Inc()
 		return c.Ok(web.Map{
@@ -311,14 +326,23 @@ func UpdateComment() web.HandlerFunc {
 			return c.HandleValidation(result)
 		}
 
+		getPost := &query.GetPostByID{PostID: action.Post.ID}
+		if err := bus.Dispatch(c, getPost); err != nil {
+			return c.Failure(err)
+		}
+
+		contentToSave := entity.CommentString(action.Content).FormatMentionJson(func(mention entity.Mention) string {
+			return fmt.Sprintf(`{"id":%d,"name":"%s"}`, mention.ID, mention.Name)
+		})
+
 		err := bus.Dispatch(c,
 			&cmd.UploadImages{
 				Images: action.Attachments,
 				Folder: "attachments",
 			},
 			&cmd.UpdateComment{
 				CommentID: action.ID,
-				Content:   action.Content,
+				Content:   contentToSave,
 			},
 			&cmd.SetAttachments{
 				Post:        action.Post,
@@ -330,6 +354,10 @@ func UpdateComment() web.HandlerFunc {
 			return c.Failure(err)
 		}
 
+		// Update the content
+
+		c.Enqueue(tasks.NotifyAboutUpdatedComment(action.Content, getPost.Result))
+
 		return c.Ok(web.Map{})
 	}
 }

app/handlers/apiv1/post_test.go

@@ -723,6 +723,36 @@ func TestPostCommentHandler(t *testing.T) {
 	Expect(newComment.Content).Equals("This is a comment!")
 }
 
+func TestPostCommentHandlerMentions(t *testing.T) {
+	RegisterT(t)
+
+	post := &entity.Post{ID: 1, Number: 1, Title: "The Post #1", Description: "The Description #1"}
+	bus.AddHandler(func(ctx context.Context, q *query.GetPostByNumber) error {
+		q.Result = post
+		return nil
+	})
+
+	var newComment *cmd.AddNewComment
+	bus.AddHandler(func(ctx context.Context, c *cmd.AddNewComment) error {
+		newComment = c
+		c.Result = &entity.Comment{ID: 1, Content: c.Content}
+		return nil
+	})
+
+	bus.AddHandler(func(ctx context.Context, c *cmd.SetAttachments) error { return nil })
+	bus.AddHandler(func(ctx context.Context, c *cmd.UploadImages) error { return nil })
+
+	code, _ := mock.NewServer().
+		OnTenant(mock.DemoTenant).
+		AsUser(mock.JonSnow).
+		AddParam("number", post.Number).
+		ExecutePost(apiv1.PostComment(), `{ "content": "Hello @{\"id\":1,\"name\":\"Jon Snow\",\"isNew\":true}!" }`)
+
+	Expect(code).Equals(http.StatusOK)
+	Expect(newComment.Post).Equals(post)
+	Expect(newComment.Content).Equals("Hello @{\"id\":1,\"name\":\"Jon Snow\"}!")
+}
+
 func TestPostCommentHandler_WithoutContent(t *testing.T) {
 	RegisterT(t)
 
@@ -758,6 +788,11 @@ func TestUpdateCommentHandler_Authorized(t *testing.T) {
 		return nil
 	})
 
+	bus.AddHandler(func(ctx context.Context, q *query.GetPostByID) error {
+		q.Result = post
+		return nil
+	})
+
 	bus.AddHandler(func(ctx context.Context, q *query.GetAttachments) error { return nil })
 	bus.AddHandler(func(ctx context.Context, c *cmd.SetAttachments) error { return nil })
 	bus.AddHandler(func(ctx context.Context, c *cmd.UploadImages) error { return nil })

app/handlers/apiv1/user.go

@@ -23,6 +23,16 @@ func ListUsers() web.HandlerFunc {
 	}
 }
 
+func ListTaggableUsers() web.HandlerFunc {
+	return func(c *web.Context) error {
+		allUsers := &query.GetAllUsersNames{}
+		if err := bus.Dispatch(c, allUsers); err != nil {
+			return c.Failure(err)
+		}
+		return c.Ok(allUsers.Result)
+	}
+}
+
 // CreateUser is used to create new users
 func CreateUser() web.HandlerFunc {
 	return func(c *web.Context) error {

app/models/dto/user.go

@@ -0,0 +1,6 @@
+package dto
+
+type UserNames struct {
+	ID   int    `json:"id"`
+	Name string `json:"name"`
+}

app/models/entity/comment.go

@@ -1,6 +1,8 @@
 package entity
 
-import "time"
+import (
+	"time"
+)
 
 type ReactionCounts struct {
 	Emoji      string `json:"emoji"`
@@ -18,4 +20,10 @@ type Comment struct {
 	EditedAt       *time.Time       `json:"editedAt,omitempty"`
 	EditedBy       *User            `json:"editedBy,omitempty"`
 	ReactionCounts []ReactionCounts `json:"reactionCounts,omitempty"`
+	Mentions       []Mention        `json:"_"`
+}
+
+func (c *Comment) ParseMentions() {
+	mentionString := CommentString(c.Content)
+	c.Mentions = mentionString.ParseMentions()
 }

app/models/entity/mention.go

@@ -0,0 +1,69 @@
+package entity
+
+import (
+	"encoding/json"
+	"regexp"
+	"strings"
+)
+
+type Mention struct {
+	ID    int    `json:"id"`
+	Name  string `json:"name"`
+	IsNew bool   `json:"isNew"`
+}
+
+type CommentString string
+
+const mentionRegex = `@{([^{}]+)}`
+
+func (commentString CommentString) ParseMentions() []Mention {
+	r, _ := regexp.Compile(mentionRegex)
+
+	// Remove escaped quotes from the input string
+	input := strings.ReplaceAll(string(commentString), `\"`, `"`)
+
+	matches := r.FindAllString(input, -1)
+
+	mentions := []Mention{}
+
+	for _, match := range matches {
+
+		jsonMention := match[1:]
+
+		var mention Mention
+		err := json.Unmarshal([]byte(jsonMention), &mention)
+		if err == nil {
+			if mention.ID > 0 && mention.Name != "" {
+				mentions = append(mentions, mention)
+			}
+		}
+	}
+
+	return mentions
+}
+
+func (mentionString CommentString) FormatMentionJson(jsonOperator func(Mention) string) string {
+
+	r, _ := regexp.Compile(mentionRegex)
+
+	// Remove escaped quotes from the input string
+	input := strings.ReplaceAll(string(mentionString), `\"`, `"`)
+
+	return r.ReplaceAllStringFunc(input, func(match string) string {
+		jsonMention := match[1:]
+
+		var mention Mention
+
+		err := json.Unmarshal([]byte(jsonMention), &mention)
+		if err != nil {
+			return match
+		}
+
+		if mention.ID == 0 || mention.Name == "" {
+			return match
+		}
+
+		return "@" + jsonOperator(mention)
+	})
+
+}

app/models/entity/mention_test.go

@@ -0,0 +1,92 @@
+package entity_test
+
+import (
+	"testing"
+
+	"github.com/getfider/fider/app/models/entity"
+
+	. "github.com/getfider/fider/app/pkg/assert"
+)
+
+func TestComment_ParseMentions(t *testing.T) {
+	RegisterT(t)
+	tests := []struct {
+		name     string
+		content  string
+		expected []entity.Mention
+	}{
+		{
+			name:     "no mentions",
+			content:  "This is a regular comment \\\" just here",
+			expected: []entity.Mention{},
+		},
+		{
+			name:     "Simple mention",
+			content:  `Hello there @{"id":1,"name":"John Doe","isNew":false} how are you`,
+			expected: []entity.Mention{{ID: 1, Name: "John Doe", IsNew: false}},
+		},
+		{
+			name:     "Simple mention 2",
+			content:  `Hello there @{"id":2,"name":"John Doe Smith","isNew":true} how are you`,
+			expected: []entity.Mention{{ID: 2, Name: "John Doe Smith", IsNew: true}},
+		},
+		{
+			name:     "Multiple mentions",
+			content:  `Hello there @{"id":2,"name":"John Doe Smith","isNew":true} and @{"id":1,"name":"John Doe","isNew":false} how are you`,
+			expected: []entity.Mention{{ID: 2, Name: "John Doe Smith", IsNew: true}, {ID: 1, Name: "John Doe", IsNew: false}},
+		},
+		{
+			name:     "Some odd JSON",
+			content:  `Hello there @{"id":2,name:"John Doe Smith","isNew":true} how are you`,
+			expected: []entity.Mention{},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			comment := &entity.Comment{Content: tt.content}
+			comment.ParseMentions()
+			Expect(comment.Mentions).Equals(tt.expected)
+		})
+	}
+}
+
+func TestStripMentionMetaData(t *testing.T) {
+	RegisterT(t)
+
+	for input, expected := range map[string]string{
+		`@{\"id\":1,\"name\":\"John Doe quoted\"}`:                                 "@John Doe quoted",
+		`@{"id":1,"name":"John Doe"}`:                                              "@John Doe",
+		`@{"id":1,"name":"JohnDoe"}`:                                               "@JohnDoe",
+		`@{\"id\":1,\"name\":\"JohnDoe quoted\"}`:                                  "@JohnDoe quoted",
+		`@{"id":1,"name":"John Smith Doe"}`:                                        "@John Smith Doe",
+		`@{\"id\":1,\"name\":\"John Smith Doe quoted\"}`:                           "@John Smith Doe quoted",
+		"Hello there how are you":                                                  "Hello there how are you",
+		`Hello there @{"id":1,"name":"John Doe"}`:                                  "Hello there @John Doe",
+		`Hello there @{"id":1,"name":"John Doe quoted"}`:                           "Hello there @John Doe quoted",
+		`Hello both @{"id":1,"name":"John Doe"} and @{"id":2,"name":"John Smith"}`: "Hello both @John Doe and @John Smith",
+	} {
+		output := entity.CommentString(input).FormatMentionJson(func(mention entity.Mention) string {
+			return mention.Name
+		})
+		Expect(output).Equals(expected)
+	}
+}
+
+func TestStripMentionMetaDataDoesntBreakUserInput(t *testing.T) {
+	RegisterT(t)
+
+	for input, expected := range map[string]string{
+		`There is nothing here`:                                         "There is nothing here",
+		`There is nothing here {ok}`:                                    "There is nothing here {ok}",
+		`This is a message for {{matt}}`:                                "This is a message for {{matt}}",
+		`This is a message for {{id:1,wiggles:true}}`:                   "This is a message for {{id:1,wiggles:true}}",
+		`Although uncommon, someone could enter @{something} like this`: "Although uncommon, someone could enter @{something} like this",
+		`Or @{"id":100,"wiggles":"yes"} something like this`:            `Or @{"id":100,"wiggles":"yes"} something like this`,
+	} {
+		output := entity.CommentString(input).FormatMentionJson(func(mention entity.Mention) string {
+			return mention.Name
+		})
+		Expect(output).Equals(expected)
+	}
+}