Put the conversation and message in a push's sealed preview (GRYT-1976)

src/services/pushPreview.test.ts

@@ -28,6 +28,13 @@ describe("sealPreview", () => {
     assert.deepEqual(open(key, CAP, blob), { t: "Alice", s: "#general · Gryt", b: "hey there" });
   });
 
+  it("carries where a tap should land, and leaves it out when there's no such place", () => {
+    const blob = sealPreview(key, CAP, { title: "Alice", body: "hi", conversationId: "dm_1", messageId: "m1", dm: true });
+    assert.deepEqual(open(key, CAP, blob), { t: "Alice", b: "hi", o: "dm_1", m: "m1", d: 1 });
+    const bare = sealPreview(key, CAP, { title: "Alice", body: "hi", conversationId: "general" });
+    assert.deepEqual(open(key, CAP, bare), { t: "Alice", b: "hi", o: "general" });
+  });
+
   it("uses the same tag the relay puts on the push", () => {
     assert.equal(capabilityTag(CAP), createHash("sha256").update(CAP).digest("hex").slice(0, 16));
   });

src/services/pushPreview.ts

@@ -3,12 +3,16 @@ import { createCipheriv, createHash, randomBytes } from "node:crypto";
 import { getServerChannel, getServerConfig } from "../db";
 
 /* A push's preview, sealed to the phone's key so the relay can't read it (GRYT-1688). AES-256-GCM:
-   0x01 | nonce | ciphertext | tag, base64url; AAD "gryt-push-1|" + capability tag; JSON {t, s?, b}. */
+   0x01 | nonce | ciphertext | tag, base64url; AAD "gryt-push-1|" + capability tag; JSON {t, s?, b, o?, m?, d?}. */
 
 export interface PushPreview {
   title: string;
   subtitle?: string;
   body: string;
+  /** Where a tap lands: the conversation, the message when one can be jumped to, and whether it's a DM. */
+  conversationId?: string;
+  messageId?: string;
+  dm?: boolean;
 }
 
 /** 32 random bytes, base64url without padding. */
@@ -33,6 +37,9 @@ export function sealPreview(previewKey: string, capability: string, preview: Pus
     t: clip(preview.title, TITLE_MAX),
     ...(preview.subtitle ? { s: clip(preview.subtitle, TITLE_MAX) } : {}),
     b: clip(preview.body, BODY_MAX),
+    ...(preview.conversationId ? { o: preview.conversationId } : {}),
+    ...(preview.messageId ? { m: preview.messageId } : {}),
+    ...(preview.dm ? { d: 1 } : {}),
   });
   const sealed = Buffer.concat([cipher.update(plain, "utf8"), cipher.final()]);
   return Buffer.concat([Buffer.from([VERSION]), nonce, sealed, cipher.getAuthTag()]).toString("base64url");
@@ -58,9 +65,22 @@ function clip(text: string, max: number): string {
 }
 
 /** "Alice", "#general · Gryt", and the first line. A DM leaves the channel out. */
-export async function messagePreview(o: { sender: string | null | undefined; channelId?: string; body: string }): Promise<PushPreview> {
+export async function messagePreview(o: {
+  sender: string | null | undefined;
+  channelId?: string;
+  body: string;
+  conversationId: string;
+  messageId?: string;
+}): Promise<PushPreview> {
   const cfg = await getServerConfig().catch(() => null);
   const server = cfg?.display_name || process.env.SERVER_NAME || "Gryt";
   const channel = o.channelId ? (await getServerChannel(o.channelId).catch(() => null))?.name : null;
-  return { title: o.sender || "Someone", subtitle: channel ? `#${channel} · ${server}` : server, body: o.body };
+  return {
+    title: o.sender || "Someone",
+    subtitle: channel ? `#${channel} · ${server}` : server,
+    body: o.body,
+    conversationId: o.conversationId,
+    ...(o.messageId ? { messageId: o.messageId } : {}),
+    ...(o.channelId ? {} : { dm: true }),
+  };
 }

src/socket/handlers/chat.ts

@@ -819,6 +819,9 @@ export function registerChatHandlers(ctx: HandlerContext): EventHandlerMap {
           sender: user.nickname,
           channelId: access.kind === "dm" ? undefined : created.conversation_id,
           body: sealed ? "New direct message" : previewText(created.text, created.attachments?.length ?? 0),
+          conversationId: created.conversation_id,
+          // A thread reply isn't in the channel's list, so that tap stops at the channel.
+          messageId: threadId ? undefined : created.message_id,
         });
 
         if (access.kind === "dm") {

src/socket/handlers/mls.ts

@@ -771,7 +771,7 @@ export function registerMlsHandlers(ctx: HandlerContext): EventHandlerMap {
           try {
             const blockers = await blockersOfSender(self);
             // Who and which server, never what: the server can't read an MLS message (GRYT-1688).
-            const preview = async () => messagePreview({ sender: (await getUserByServerId(self))?.nickname, body: "New direct message" });
+            const preview = async () => messagePreview({ sender: (await getUserByServerId(self))?.nickname, body: "New direct message", conversationId: payload.conversationId });
             pushNotify(clientsInfo, memberIds.filter((id) => id !== self && !blockers.has(id)), "dm", payload.conversationId, { preview });
           } catch (err) {
             consola.warn("mls push failed", payload.conversationId, err);

src/socket/handlers/pushAudience.test.ts

@@ -390,7 +390,13 @@ describe("previews sealed to the phone (GRYT-1688)", () => {
     assert.deepEqual(await woken(), ["Carol:mention"]);
     const body = JSON.parse(hits[0].body) as { kind: string; preview: string };
     assert.ok(!hits[0].body.includes("green"), "the relay could read the message");
-    assert.deepEqual(openPreview(key, carol.capability, body.preview), {
+    const opened = openPreview(key, carol.capability, body.preview) as Record<string, unknown>;
+    assert.equal(opened.o, OPEN);
+    assert.equal(typeof opened.m, "string", "a tap lands on the message");
+    assert.equal(opened.d, undefined);
+    delete opened.o;
+    delete opened.m;
+    assert.deepEqual(opened, {
       t: "Alice", s: "#General · Gryt", b: "@Carol the build is green",
     });
   });
@@ -402,7 +408,13 @@ describe("previews sealed to the phone (GRYT-1688)", () => {
     await send(erin, dm, "lunch?");
     assert.deepEqual(await woken(), ["Dave:dm"]);
     const body = JSON.parse(hits[0].body) as { preview: string };
-    assert.deepEqual(openPreview(key, dave.capability, body.preview), { t: "Erin", s: "Gryt", b: "lunch?" });
+    const opened = openPreview(key, dave.capability, body.preview) as Record<string, unknown>;
+    assert.equal(opened.d, 1, "a tap opens it on the Messages tab");
+    assert.equal(opened.o, dm);
+    delete opened.o;
+    delete opened.m;
+    delete opened.d;
+    assert.deepEqual(opened, { t: "Erin", s: "Gryt", b: "lunch?" });
   });
 
   it("a phone without a key gets the relay's fixed text, as before", async () => {