Fix Slack file visibility in history

Author: ctate

packages/@emulators/slack/src/__tests__/slack.test.ts

@@ -3150,7 +3150,7 @@ describe("Slack plugin - files", () => {
       headers: authHeaders(),
       body: JSON.stringify({
         files: [{ id: upload.file_id, title: "Mixed" }],
-        channels: `${publicChannel},${privateChannel.channel_id}`,
+        channels: `${privateChannel.channel_id},${publicChannel}`,
       }),
     });
     expect(((await completeRes.json()) as any).ok).toBe(true);
@@ -3188,6 +3188,18 @@ describe("Slack plugin - files", () => {
     const publicList = (await publicListRes.json()) as any;
     expect(publicList.ok).toBe(true);
     expect(publicList.files.map((file: any) => file.id)).toContain(upload.file_id);
+
+    const historyRes = await app.request(`${base}/api/conversations.history`, {
+      method: "POST",
+      headers: outsiderHeaders,
+      body: JSON.stringify({ channel: publicChannel }),
+    });
+    const history = (await historyRes.json()) as any;
+    expect(history.ok).toBe(true);
+    const fileShare = history.messages.find((message: any) => message.subtype === "file_share");
+    expect(fileShare.files[0].channels).toEqual([publicChannel]);
+    expect(fileShare.files[0].groups).toEqual([]);
+    expect(fileShare.files[0].shares.private).toBeUndefined();
   });
 
   it("does not partially complete multi-file uploads when one file is invalid", async () => {

packages/@emulators/slack/src/routes/conversations.ts

@@ -1,5 +1,5 @@
 import type { RouteContext } from "@emulators/core";
-import type { SlackChannel, SlackMessage, SlackUser } from "../entities.js";
+import type { SlackChannel, SlackFile, SlackFileShare, SlackMessage, SlackUser } from "../entities.js";
 import { getSlackStore } from "../store.js";
 import {
   formatSlackMessage,
@@ -33,6 +33,35 @@ export function conversationsRoutes(ctx: RouteContext): void {
     getChannelMemberKey(channel, user, userId) !== undefined;
   const canReadConversation = (channel: SlackChannel, user: SlackUser | undefined, userId: string) =>
     !channel.is_private || isChannelMember(channel, user, userId);
+  const visibleFileChannelIds = (file: SlackFile, authUser: { login: string }) => {
+    const authSlackUser = getAuthSlackUser(authUser);
+    const authUserId = authSlackUser?.user_id ?? authUser.login;
+    return fileChannels(file).filter((channelId) => {
+      const channel = ss().channels.findOneBy("channel_id", channelId);
+      return channel ? canReadConversation(channel, authSlackUser, authUserId) : false;
+    });
+  };
+  const visibleFileForAuth = (file: SlackFile, authUser: { login: string }): SlackFile => {
+    const visibleIds = new Set(visibleFileChannelIds(file, authUser));
+    const publicShares = filterVisibleShares(file.shares.public, visibleIds);
+    const privateShares = filterVisibleShares(file.shares.private, visibleIds);
+    const shares: SlackFile["shares"] = {};
+    if (publicShares) shares.public = publicShares;
+    if (privateShares) shares.private = privateShares;
+
+    return {
+      ...file,
+      channels: file.channels.filter((channelId) => visibleIds.has(channelId)),
+      groups: file.groups.filter((channelId) => visibleIds.has(channelId)),
+      ims: file.ims.filter((channelId) => visibleIds.has(channelId)),
+      shares,
+    };
+  };
+  const formatSlackMessageForAuth = (msg: SlackMessage, authUser: { login: string }) =>
+    formatSlackMessage({
+      ...msg,
+      ...(msg.files ? { files: msg.files.map((file) => visibleFileForAuth(file, authUser)) } : {}),
+    });
   const dispatchConversationEvent = async (type: string, event: Record<string, unknown>) => {
     await webhooks.dispatch(
       type,
@@ -428,7 +457,7 @@ export function conversationsRoutes(ctx: RouteContext): void {
     const nextCursor = hasMore ? allMessages[startIndex + limit].ts : "";
 
     return slackOk(c, {
-      messages: page.map(formatSlackMessage),
+      messages: page.map((message) => formatSlackMessageForAuth(message, authUser)),
       has_more: hasMore,
       response_metadata: { next_cursor: nextCursor },
     });
@@ -458,7 +487,7 @@ export function conversationsRoutes(ctx: RouteContext): void {
       .sort((a, b) => (a.ts > b.ts ? 1 : -1));
 
     return slackOk(c, {
-      messages: allMessages.map(formatSlackMessage),
+      messages: allMessages.map((message) => formatSlackMessageForAuth(message, authUser)),
       has_more: false,
     });
   });
@@ -920,6 +949,15 @@ function findNamedChannel(channels: SlackChannel[], name: string): SlackChannel
   return channels.find((ch) => !ch.is_im && !ch.is_mpim && ch.name === name);
 }
 
+function fileChannels(file: SlackFile): string[] {
+  return [...file.channels, ...file.groups, ...file.ims];
+}
+
+function filterVisibleShares(shares: Record<string, SlackFileShare[]> | undefined, visibleIds: Set<string>) {
+  const entries = Object.entries(shares ?? {}).filter(([channelId]) => visibleIds.has(channelId));
+  return entries.length > 0 ? Object.fromEntries(entries) : undefined;
+}
+
 function channelTypeLetter(ch: SlackChannel): "C" | "D" | "G" {
   if (ch.is_im) return "D";
   if (ch.is_private || ch.is_mpim) return "G";

packages/emulate/src/registry.ts

@@ -215,7 +215,7 @@ export const SERVICE_REGISTRY: Record<ServiceName, ServiceEntry> = {
 
   slack: {
     label: "Slack API emulator",
-    endpoints: "auth, chat, conversations, users, reactions, team, OAuth, incoming webhooks",
+    endpoints: "auth, chat, conversations, users, files, reactions, team, OAuth, incoming webhooks",
     async load() {
       const mod = await import("@emulators/slack");
       return { plugin: mod.slackPlugin, seedFromConfig: mod.seedFromConfig };