Refactor contact sync processing

ts/textsecure/ContactsParser.ts

@@ -30,10 +30,12 @@ export type ModifiedGroupDetails = MessageWithAvatar<Proto.GroupDetails>;
 
 export type ModifiedContactDetails = MessageWithAvatar<Proto.ContactDetails>;
 
-class ParserBase<
+abstract class ParserBase<
   Message extends OptionalAvatar,
-  Decoder extends DecoderBase<Message>
-> {
+  Decoder extends DecoderBase<Message>,
+  Result
+> implements Iterable<Result>
+{
   protected readonly reader: protobuf.Reader;
 
   constructor(bytes: Uint8Array, private readonly decoder: Decoder) {
@@ -83,17 +85,28 @@ class ParserBase<
       return undefined;
     }
   }
+
+  public abstract next(): Result | undefined;
+
+  *[Symbol.iterator](): Iterator<Result> {
+    let result = this.next();
+    while (result !== undefined) {
+      yield result;
+      result = this.next();
+    }
+  }
 }
 
 export class GroupBuffer extends ParserBase<
   Proto.GroupDetails,
-  typeof Proto.GroupDetails
+  typeof Proto.GroupDetails,
+  ModifiedGroupDetails
 > {
   constructor(arrayBuffer: Uint8Array) {
     super(arrayBuffer, Proto.GroupDetails);
   }
 
-  public next(): ModifiedGroupDetails | undefined {
+  public override next(): ModifiedGroupDetails | undefined {
     const proto = this.decodeDelimited();
     if (!proto) {
       return undefined;
@@ -120,13 +133,14 @@ export class GroupBuffer extends ParserBase<
 
 export class ContactBuffer extends ParserBase<
   Proto.ContactDetails,
-  typeof Proto.ContactDetails
+  typeof Proto.ContactDetails,
+  ModifiedContactDetails
 > {
   constructor(arrayBuffer: Uint8Array) {
     super(arrayBuffer, Proto.ContactDetails);
   }
 
-  public next(): ModifiedContactDetails | undefined {
+  public override next(): ModifiedContactDetails | undefined {
     const proto = this.decodeDelimited();
     if (!proto) {
       return undefined;

ts/textsecure/MessageReceiver.ts

@@ -104,7 +104,6 @@ import {
   StickerPackEvent,
   ReadSyncEvent,
   ViewSyncEvent,
-  ContactEvent,
   ContactSyncEvent,
   GroupEvent,
   GroupSyncEvent,
@@ -561,11 +560,6 @@ export default class MessageReceiver
     handler: (ev: ViewSyncEvent) => void
   ): void;
 
-  public override addEventListener(
-    name: 'contact',
-    handler: (ev: ContactEvent) => void
-  ): void;
-
   public override addEventListener(
     name: 'contactSync',
     handler: (ev: ContactSyncEvent) => void
@@ -2748,6 +2742,9 @@ export default class MessageReceiver
       return this.handleSentMessage(envelope, sentMessage);
     }
     if (syncMessage.contacts) {
+      // Note: we do not return here because we don't want to block the next
+      //   message on this attachment download and a lot of processing of that
+      //   attachment.
       this.handleContacts(envelope, syncMessage.contacts);
       return;
     }
@@ -3068,26 +3065,14 @@ export default class MessageReceiver
 
     this.removeFromCache(envelope);
 
-    // Note: we do not return here because we don't want to block the next message on
-    //   this attachment download and a lot of processing of that attachment.
     const attachmentPointer = await this.handleAttachment(blob);
-    const results = [];
     const contactBuffer = new ContactBuffer(attachmentPointer.data);
-    let contactDetails = contactBuffer.next();
-    while (contactDetails !== undefined) {
-      const contactEvent = new ContactEvent(
-        contactDetails,
-        envelope.receivedAtCounter
-      );
-      results.push(this.dispatchAndWait(contactEvent));
 
-      contactDetails = contactBuffer.next();
-    }
-
-    await Promise.all(results);
-
-    const finalEvent = new ContactSyncEvent();
-    await this.dispatchAndWait(finalEvent);
+    const contactSync = new ContactSyncEvent(
+      Array.from(contactBuffer),
+      envelope.receivedAtCounter
+    );
+    await this.dispatchAndWait(contactSync);
 
     log.info('handleContacts: finished');
   }

ts/textsecure/messageReceiverEvents.ts

@@ -73,17 +73,11 @@ export class ErrorEvent extends Event {
   }
 }
 
-export class ContactEvent extends Event {
+export class ContactSyncEvent extends Event {
   constructor(
-    public readonly contactDetails: ModifiedContactDetails,
+    public readonly contacts: ReadonlyArray<ModifiedContactDetails>,
     public readonly receivedAtCounter: number
   ) {
-    super('contact');
-  }
-}
-
-export class ContactSyncEvent extends Event {
-  constructor() {
     super('contactSync');
   }
 }