Formalize our one-to-many relationship between Slack and Matrix events

We may produce multiple Matrix events per Slack events, if the Slack events contains text with attachments.
This should have been forbidden with a DB constraint, but for some reason it happened regardless.

This updates the constraint to match reality, differentiating Matrix events by the type of incoming Slack event.
For backwards compatibility reasons getEventBySlackId() returns the "main" Matrix event.

src/BridgedRoom.ts

@@ -878,7 +878,7 @@ export class BridgedRoom {
                 formatted_body: `<a href="${link}">${file.name}</a>`,
                 msgtype: "m.text",
             };
-            await ghost.sendMessage(this.matrixRoomId, messageContent, channelId, slackEventId);
+            await ghost.sendMessage(this.matrixRoomId, messageContent, channelId, slackEventId, { type: "attachment" });
             return;
         }
 
@@ -917,7 +917,7 @@ export class BridgedRoom {
                 formatted_body: htmlCode,
                 msgtype: "m.text",
             };
-            await ghost.sendMessage(this.matrixRoomId, messageContent, channelId, slackEventId);
+            await ghost.sendMessage(this.matrixRoomId, messageContent, channelId, slackEventId, { type: "attachment" });
             return;
         }
 
@@ -954,6 +954,7 @@ export class BridgedRoom {
             slackFileToMatrixMessage(file, fileContentUri, thumbnailContentUri),
             channelId,
             slackEventId,
+            { type: "attachment" },
         );
     }
 

src/SlackGhost.ts

@@ -19,7 +19,7 @@ import * as Slackdown from "Slackdown";
 import { ISlackUser } from "./BaseSlackHandler";
 import { WebClient } from "@slack/web-api";
 import { BotsInfoResponse, UsersInfoResponse } from "./SlackResponses";
-import { UserEntry, Datastore } from "./datastore/Models";
+import { UserEntry, Datastore, EventEntryExtra } from "./datastore/Models";
 import axios from "axios";
 
 const log = new Logger("SlackGhost");
@@ -368,7 +368,13 @@ export class SlackGhost {
         await this.sendMessage(roomId, content, slackRoomID, slackEventTS);
     }
 
-    public async sendMessage(roomId: string, msg: Record<string, unknown>, slackRoomId: string, slackEventTs: string): Promise<{event_id: string}> {
+    public async sendMessage(
+        roomId: string,
+        msg: Record<string, unknown>,
+        slackRoomId: string,
+        slackEventTs: string,
+        eventExtras?: EventEntryExtra,
+    ): Promise<{event_id: string}> {
         if (!this._intent) {
             throw Error('No intent associated with ghost');
         }
@@ -383,6 +389,7 @@ export class SlackGhost {
             matrixEvent.event_id,
             slackRoomId,
             slackEventTs,
+            eventExtras,
         );
 
         return {

src/datastore/Models.ts

@@ -50,6 +50,7 @@ export interface EventEntry {
 }
 
 export interface EventEntryExtra {
+    type?: 'attachment';
     slackThreadMessages?: string[];
 }
 

src/datastore/postgres/PgDatastore.ts

@@ -64,7 +64,7 @@ export interface SchemaRunUserMessage {
 type SchemaRunFn = (db: IDatabase<unknown>) => Promise<void|{userMessages: SchemaRunUserMessage[]}>;
 
 export class PgDatastore implements Datastore, ClientEncryptionStore, ProvisioningStore {
-    public static readonly LATEST_SCHEMA = 16;
+    public static readonly LATEST_SCHEMA = 17;
     public readonly postgresDb: IDatabase<any>;
 
     constructor(connectionString: string) {
@@ -180,15 +180,18 @@ export class PgDatastore implements Datastore, ClientEncryptionStore, Provisioni
 
     public async getEventBySlackId(slackChannel: string, slackTs: string): Promise<EventEntry|null> {
         log.debug(`getEventBySlackId: ${slackChannel} ${slackTs}`);
-        return this.postgresDb.oneOrNone(
-            "SELECT * FROM events WHERE slackChannel = ${slackChannel} AND slackTs = ${slackTs} LIMIT 1",
-            { slackChannel, slackTs }, e => e && {
-                roomId: e.roomid,
-                eventId: e.eventid,
-                slackChannelId: slackChannel,
-                slackTs,
-                _extras: JSON.parse(e.extras),
-            });
+        const events = await this.postgresDb.manyOrNone(
+            "SELECT * FROM events WHERE slackChannel = ${slackChannel} AND slackTs = ${slackTs}",
+            { slackChannel, slackTs }
+        ).then(entries => entries.map(e => ({
+            roomId: e.roomid,
+            eventId: e.eventid,
+            slackChannelId: slackChannel,
+            slackTs,
+            _extras: JSON.parse(e.extras) as EventEntryExtra,
+        })));
+
+        return events.find(e => e._extras.type !== 'attachment') ?? null;
     }
 
     public async deleteEventByMatrixId(roomId: string, eventId: string): Promise<null> {