Save group send endorsements

ts/types/GroupSendEndorsements.ts

@@ -0,0 +1,79 @@
+// Copyright 2024 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+import { z } from 'zod';
+import { aciSchema, type AciString } from './ServiceId';
+import * as Bytes from '../Bytes';
+
+const GROUPV2_ID_LENGTH = 32; // 32 bytes
+
+/**
+ * The endorsement for a single group member.
+ * Used when sending a group message.
+ */
+export type GroupSendCombinedEndorsementRecord = Readonly<{
+  groupId: string;
+  /** Unix timestamp in seconds */
+  expiration: number;
+  endorsement: Uint8Array;
+}>;
+
+/**
+ * The endorsement for a single group member.
+ *
+ * Used when:
+ * - Sending a group message to an individual member[1]
+ * - Fetching a pre-key bundle for an individual member[1]
+ * - Fetching a unversioned profile for an individual member[1]
+ *
+ * [1]: As a fallback when the access key comes back unauthorized.
+ */
+export type GroupSendMemberEndorsementRecord = Readonly<{
+  groupId: string;
+  memberAci: AciString;
+  /** Unix timestamp in seconds */
+  expiration: number;
+  endorsement: Uint8Array;
+}>;
+
+/**
+ * Deserialized data from a group send endorsements response.
+ * Used for updating the database in a single transaction.
+ */
+export type GroupSendEndorsementsData = Readonly<{
+  combinedEndorsement: GroupSendCombinedEndorsementRecord;
+  memberEndorsements: ReadonlyArray<GroupSendMemberEndorsementRecord>;
+}>;
+
+const groupIdSchema = z.string().refine(value => {
+  return Bytes.fromBase64(value).byteLength === GROUPV2_ID_LENGTH;
+});
+
+/**
+ * Unix timestamp in seconds.
+ * Used to trigger a group refresh when the expiration is less than 2 hours away.
+ */
+export const groupSendEndorsementExpirationSchema = z.number().int().positive(); // not 0
+
+export const groupSendEndorsementSchema = z
+  .instanceof(Uint8Array)
+  .refine(array => {
+    return array.byteLength > 0; // not empty
+  });
+
+export const groupSendCombinedEndorsementSchema = z.object({
+  groupId: groupIdSchema,
+  expiration: groupSendEndorsementExpirationSchema,
+  endorsement: groupSendEndorsementSchema,
+});
+
+export const groupSendMemberEndorsementSchema = z.object({
+  groupId: groupIdSchema,
+  memberAci: aciSchema,
+  expiration: groupSendEndorsementExpirationSchema,
+  endorsement: groupSendEndorsementSchema,
+});
+
+export const groupSendEndorsementsDataSchema = z.object({
+  combinedEndorsement: groupSendCombinedEndorsementSchema,
+  memberEndorsements: z.array(groupSendMemberEndorsementSchema).min(1),
+});