feat: track chat file associations with chat_file_links on chats (#23537)

Needed by #23833 Adds a `chat_file_links` association table to track which files are associated with each chat. - `AppendChatFileIDs` query links a file to a chat with deduplication - `GetChatFileMetadataByIDs` query returns lightweight file metadata by IDs - Tool-created files (e.g. `propose_plan`) are linked to the chat after insert - User-uploaded files are linked to the chat when the referencing message is sent - Single-chat GET endpoint hydrates `files: ChatFileMetadata[]` on the response > 🤖 Created by Coder Agents and massaged into shape by a human.
2026-09-24 15:04:27 +08:00 · 2026-04-07 12:05:29 +01:00
parent beb99c17de
commit d5a1792f07
26 changed files with 1175 additions and 60 deletions
@@ -413,7 +413,7 @@ func (api *API) postChats(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	contentBlocks, titleSource, inputError := createChatInputFromRequest(ctx, api.Database, req)
+	contentBlocks, titleSource, fileIDs, inputError := createChatInputFromRequest(ctx, api.Database, req)
 	if inputError != nil {
 		httpapi.Write(ctx, rw, http.StatusBadRequest, *inputError)
 		return
@@ -524,7 +524,32 @@ func (api *API) postChats(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	httpapi.Write(ctx, rw, http.StatusCreated, db2sdk.Chat(chat, nil))
+	// Link any user-uploaded files referenced in the initial
+	// message to this newly created chat (best-effort; cap
+	// enforced in SQL).
+	unlinked, capExceeded := api.linkFilesToChat(ctx, chat.ID, fileIDs)
+
+	// Re-read the chat so the response reflects the authoritative
+	// database state (file links are deduped in the join table).
+	chat, err = api.Database.GetChatByID(ctx, chat.ID)
+	if err != nil {
+		httpapi.Write(ctx, rw, http.StatusInternalServerError, codersdk.Response{
+			Message: "Failed to read back chat after creation.",
+			Detail:  err.Error(),
+		})
+		return
+	}
+
+	chatFiles := api.fetchChatFileMetadata(ctx, chat.ID)
+	response := db2sdk.Chat(chat, nil, chatFiles)
+	if len(unlinked) > 0 {
+		if capExceeded {
+			response.Warnings = append(response.Warnings, fileLinkCapWarning(len(unlinked)))
+		} else {
+			response.Warnings = append(response.Warnings, fileLinkErrorWarning(len(unlinked)))
+		}
+	}
+	httpapi.Write(ctx, rw, http.StatusCreated, response)
 }

 // EXPERIMENTAL: this endpoint is experimental and is subject to change.
@@ -1301,7 +1326,11 @@ func (api *API) getChat(rw http.ResponseWriter, r *http.Request) {
 			slog.Error(err),
 		)
 	}
-	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(chat, diffStatus))
+
+	// Hydrate file metadata for all files linked to this chat.
+	chatFiles := api.fetchChatFileMetadata(ctx, chat.ID)
+
+	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(chat, diffStatus, chatFiles))
 }

 // EXPERIMENTAL: this endpoint is experimental and is subject to change.
@@ -1791,7 +1820,7 @@ func (api *API) postChatMessages(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	contentBlocks, _, inputError := createChatInputFromParts(ctx, api.Database, req.Content, "content")
+	contentBlocks, _, fileIDs, inputError := createChatInputFromParts(ctx, api.Database, req.Content, "content")
 	if inputError != nil {
 		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
 			Message: inputError.Message,
@@ -1873,6 +1902,9 @@ func (api *API) postChatMessages(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

+	// Link any user-uploaded files referenced in this message
+	// to the chat (best-effort; cap enforced in SQL).
+	unlinked, capExceeded := api.linkFilesToChat(ctx, chatID, fileIDs)
 	response := codersdk.CreateChatMessageResponse{Queued: sendResult.Queued}
 	if sendResult.Queued {
 		if sendResult.QueuedMessage != nil {
@@ -1882,6 +1914,13 @@ func (api *API) postChatMessages(rw http.ResponseWriter, r *http.Request) {
 		message := convertChatMessage(sendResult.Message)
 		response.Message = &message
 	}
+	if len(unlinked) > 0 {
+		if capExceeded {
+			response.Warnings = append(response.Warnings, fileLinkCapWarning(len(unlinked)))
+		} else {
+			response.Warnings = append(response.Warnings, fileLinkErrorWarning(len(unlinked)))
+		}
+	}

 	httpapi.Write(ctx, rw, http.StatusOK, response)
 }
@@ -1915,7 +1954,7 @@ func (api *API) patchChatMessage(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	contentBlocks, _, inputError := createChatInputFromParts(ctx, api.Database, req.Content, "content")
+	contentBlocks, _, fileIDs, inputError := createChatInputFromParts(ctx, api.Database, req.Content, "content")
 	if inputError != nil {
 		httpapi.Write(ctx, rw, http.StatusBadRequest, codersdk.Response{
 			Message: inputError.Message,
@@ -1954,8 +1993,20 @@ func (api *API) patchChatMessage(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	message := convertChatMessage(editResult.Message)
-	httpapi.Write(ctx, rw, http.StatusOK, message)
+	// Link any user-uploaded files referenced in the edited
+	// message to the chat (best-effort; cap enforced in SQL).
+	unlinked, capExceeded := api.linkFilesToChat(ctx, chat.ID, fileIDs)
+	response := codersdk.EditChatMessageResponse{
+		Message: convertChatMessage(editResult.Message),
+	}
+	if len(unlinked) > 0 {
+		if capExceeded {
+			response.Warnings = append(response.Warnings, fileLinkCapWarning(len(unlinked)))
+		} else {
+			response.Warnings = append(response.Warnings, fileLinkErrorWarning(len(unlinked)))
+		}
+	}
+	httpapi.Write(ctx, rw, http.StatusOK, response)
 }

 // EXPERIMENTAL: this endpoint is experimental and is subject to change.
@@ -2232,7 +2283,7 @@ func (api *API) interruptChat(rw http.ResponseWriter, r *http.Request) {
 		chat = updatedChat
 	}

-	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(chat, nil))
+	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(chat, nil, nil))
 }

 // EXPERIMENTAL: this endpoint is experimental and is subject to change.
@@ -2276,7 +2327,7 @@ func (api *API) regenerateChatTitle(rw http.ResponseWriter, r *http.Request) {
 		return
 	}

-	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(updatedChat, nil))
+	httpapi.Write(ctx, rw, http.StatusOK, db2sdk.Chat(updatedChat, nil, nil))
 }

 // EXPERIMENTAL: this endpoint is experimental and is subject to change.
@@ -3688,6 +3739,7 @@ func (api *API) chatFileByID(rw http.ResponseWriter, r *http.Request) {
 func createChatInputFromRequest(ctx context.Context, db database.Store, req codersdk.CreateChatRequest) (
 	[]codersdk.ChatMessagePart,
 	string,
+	[]uuid.UUID,
 	*codersdk.Response,
 ) {
 	return createChatInputFromParts(ctx, db, req.Content, "content")
@@ -3698,14 +3750,15 @@ func createChatInputFromParts(
 	db database.Store,
 	parts []codersdk.ChatInputPart,
 	fieldName string,
-) ([]codersdk.ChatMessagePart, string, *codersdk.Response) {
+) ([]codersdk.ChatMessagePart, string, []uuid.UUID, *codersdk.Response) {
 	if len(parts) == 0 {
-		return nil, "", &codersdk.Response{
+		return nil, "", nil, &codersdk.Response{
 			Message: "Content is required.",
 			Detail:  "Content cannot be empty.",
 		}
 	}

+	var fileIDs []uuid.UUID
 	content := make([]codersdk.ChatMessagePart, 0, len(parts))
 	textParts := make([]string, 0, len(parts))
 	for i, part := range parts {
@@ -3713,7 +3766,7 @@ func createChatInputFromParts(
 		case string(codersdk.ChatInputPartTypeText):
 			text := strings.TrimSpace(part.Text)
 			if text == "" {
-				return nil, "", &codersdk.Response{
+				return nil, "", nil, &codersdk.Response{
 					Message: "Invalid input part.",
 					Detail:  fmt.Sprintf("%s[%d].text cannot be empty.", fieldName, i),
 				}
@@ -3722,7 +3775,7 @@ func createChatInputFromParts(
 			textParts = append(textParts, text)
 		case string(codersdk.ChatInputPartTypeFile):
 			if part.FileID == uuid.Nil {
-				return nil, "", &codersdk.Response{
+				return nil, "", nil, &codersdk.Response{
 					Message: "Invalid input part.",
 					Detail:  fmt.Sprintf("%s[%d].file_id is required for file parts.", fieldName, i),
 				}
@@ -3733,20 +3786,23 @@ func createChatInputFromParts(
 			chatFile, err := db.GetChatFileByID(ctx, part.FileID)
 			if err != nil {
 				if httpapi.Is404Error(err) {
-					return nil, "", &codersdk.Response{
+					return nil, "", nil, &codersdk.Response{
 						Message: "Invalid input part.",
 						Detail:  fmt.Sprintf("%s[%d].file_id references a file that does not exist.", fieldName, i),
 					}
 				}
-				return nil, "", &codersdk.Response{
+				return nil, "", nil, &codersdk.Response{
 					Message: "Internal error.",
 					Detail:  fmt.Sprintf("Failed to retrieve file for %s[%d].", fieldName, i),
 				}
 			}
 			content = append(content, codersdk.ChatMessageFile(part.FileID, chatFile.Mimetype))
+			fileIDs = append(fileIDs, part.FileID)
+		// file-reference parts carry inline code snippets, not uploaded
+		// files. They have no FileID and are excluded from file tracking.
 		case string(codersdk.ChatInputPartTypeFileReference):
 			if part.FileName == "" {
-				return nil, "", &codersdk.Response{
+				return nil, "", nil, &codersdk.Response{
 					Message: "Invalid input part.",
 					Detail:  fmt.Sprintf("%s[%d].file_name cannot be empty for file-reference.", fieldName, i),
 				}
@@ -3764,7 +3820,7 @@ func createChatInputFromParts(
 			}
 			textParts = append(textParts, sb.String())
 		default:
-			return nil, "", &codersdk.Response{
+			return nil, "", nil, &codersdk.Response{
 				Message: "Invalid input part.",
 				Detail: fmt.Sprintf(
 					"%s[%d].type %q is not supported.",
@@ -3779,13 +3835,13 @@ func createChatInputFromParts(
 	// Allow file-only messages. The titleSource may be empty
 	// when only file parts are provided, callers handle this.
 	if len(content) == 0 {
-		return nil, "", &codersdk.Response{
+		return nil, "", nil, &codersdk.Response{
 			Message: "Content is required.",
 			Detail:  fmt.Sprintf("%s must include at least one text or file part.", fieldName),
 		}
 	}
 	titleSource := strings.TrimSpace(strings.Join(textParts, " "))
-	return content, titleSource, nil
+	return content, titleSource, fileIDs, nil
 }

 func chatTitleFromMessage(message string) string {
@@ -3820,6 +3876,70 @@ func truncateRunes(value string, maxLen int) string {
 	return string(runes[:maxLen])
 }

+// linkFilesToChat inserts file-link rows into the chat_file_links
+// join table. Cap enforcement and dedup are handled atomically in
+// SQL. On success returns (nil, false). On failure returns the full
+// input fileIDs slice — linking is all-or-nothing because the
+// SQL operates on the batch atomically. capExceeded indicates
+// whether the failure was due to the cap being exceeded (true)
+// or a database error (false).
+// Failures are logged but never block the caller.
+func (api *API) linkFilesToChat(ctx context.Context, chatID uuid.UUID, fileIDs []uuid.UUID) (unlinked []uuid.UUID, capExceeded bool) {
+	if len(fileIDs) == 0 {
+		return nil, false
+	}
+	rejected, err := api.Database.LinkChatFiles(ctx, database.LinkChatFilesParams{
+		ChatID:       chatID,
+		MaxFileLinks: int32(codersdk.MaxChatFileIDs),
+		FileIds:      fileIDs,
+	})
+	if err != nil {
+		api.Logger.Error(ctx, "failed to link files to chat",
+			slog.F("chat_id", chatID),
+			slog.F("file_ids", fileIDs),
+			slog.Error(err),
+		)
+		return fileIDs, false
+	}
+	if rejected > 0 {
+		api.Logger.Warn(ctx, "file cap reached, files not linked",
+			slog.F("chat_id", chatID),
+			slog.F("file_ids", fileIDs),
+			slog.F("max_file_links", codersdk.MaxChatFileIDs),
+		)
+		return fileIDs, true
+	}
+	return nil, false
+}
+
+// fileLinkCapWarning builds a user-facing warning when a batch
+// of file IDs was atomically rejected because the resulting
+// array would exceed the per-chat file cap.
+func fileLinkCapWarning(count int) string {
+	return fmt.Sprintf("file linking skipped: batch of %d file(s) would exceed limit of %d", count, codersdk.MaxChatFileIDs)
+}
+
+// fileLinkErrorWarning builds a user-facing warning when a
+// database error prevented linking files to a chat.
+func fileLinkErrorWarning(count int) string {
+	return fmt.Sprintf("%d file(s) could not be linked due to a server error", count)
+}
+
+// fetchChatFileMetadata returns metadata for all files linked to
+// the given chat. Errors are logged and result in a nil return
+// (callers treat file metadata as best-effort).
+func (api *API) fetchChatFileMetadata(ctx context.Context, chatID uuid.UUID) []database.GetChatFileMetadataByChatIDRow {
+	rows, err := api.Database.GetChatFileMetadataByChatID(ctx, chatID)
+	if err != nil {
+		api.Logger.Error(ctx, "failed to fetch chat file metadata",
+			slog.F("chat_id", chatID),
+			slog.Error(err),
+		)
+		return nil
+	}
+	return rows
+}
+
 func convertChatCostModelBreakdown(model database.GetChatCostPerModelRow) codersdk.ChatCostModelBreakdown {
 	displayName := strings.TrimSpace(model.DisplayName)
 	if displayName == "" {