feat: Allow webhooks to fetch, edit and delete messages in threads

src/structures/Webhook.js

@@ -105,6 +105,8 @@ class Webhook {
    * @property {MessageAttachment[]} [attachments] Attachments to send with the message
    * @property {MessageActionRow[]|MessageActionRowOptions[]} [components]
    * Action rows containing interactive components for the message (buttons, select menus)
+   * @property {Snowflake} [threadId] The id of the thread this message belongs to
+   * <info>For interaction webhooks, this property is ignored</info>
    */
 
   /**
@@ -235,18 +237,38 @@ class Webhook {
     return this;
   }
 
+  /**
+   * Options that can be passed into fetchMessage.
+   * @typedef {options} WebhookFetchMessageOptions
+   * @property {boolean} [cache=true] Whether to cache the message.
+   * @property {Snowflake} [threadId] The id of the thread this message belongs to.
+   * <info>For interaction webhooks, this property is ignored</info>
+   */
+
   /**
    * Gets a message that was sent by this webhook.
    * @param {Snowflake|'@original'} message The id of the message to fetch
-   * @param {boolean} [cache=true] Whether to cache the message
+   * @param {WebhookFetchMessageOptions|boolean} [cacheOrOptions={}] The options to provide to fetch the message.
+   * A **deprecated** boolean may be passed instead to specify whether to cache the message.
    * @returns {Promise<Message|APIMessage>} Returns the raw message data if the webhook was instantiated as a
    * {@link WebhookClient} or if the channel is uncached, otherwise a {@link Message} will be returned
    */
-  async fetchMessage(message, cache = true) {
+  async fetchMessage(message, cacheOrOptions = { cache: true }) {
+    if (typeof cacheOrOptions === 'boolean') {
+      cacheOrOptions = { cache: cacheOrOptions };
+    }
+
     if (!this.token) throw new Error('WEBHOOK_TOKEN_UNAVAILABLE');
 
-    const data = await this.client.api.webhooks(this.id, this.token).messages(message).get();
-    return this.client.channels?.cache.get(data.channel_id)?.messages._add(data, cache) ?? data;
+    const data = await this.client.api
+      .webhooks(this.id, this.token)
+      .messages(message)
+      .get({
+        query: {
+          thread_id: cacheOrOptions.threadId,
+        },
+      });
+    return this.client.channels?.cache.get(data.channel_id)?.messages._add(data, cacheOrOptions.cache) ?? data;
   }
 
   /**
@@ -269,7 +291,13 @@ class Webhook {
     const d = await this.client.api
       .webhooks(this.id, this.token)
       .messages(typeof message === 'string' ? message : message.id)
-      .patch({ data, files });
+      .patch({
+        data,
+        files,
+        query: {
+          thread_id: messagePayload.options.threadId,
+        },
+      });
 
     const messageManager = this.client.channels?.cache.get(d.channel_id)?.messages;
     if (!messageManager) return d;
@@ -294,15 +322,20 @@ class Webhook {
   /**
    * Delete a message that was sent by this webhook.
    * @param {MessageResolvable|'@original'} message The message to delete
+   * @param {Snowflake} [threadId] The id of the thread this message belongs to
    * @returns {Promise<void>}
    */
-  async deleteMessage(message) {
+  async deleteMessage(message, threadId) {
     if (!this.token) throw new Error('WEBHOOK_TOKEN_UNAVAILABLE');
 
     await this.client.api
       .webhooks(this.id, this.token)
       .messages(typeof message === 'string' ? message : message.id)
-      .delete();
+      .delete({
+        query: {
+          thread_id: threadId,
+        },
+      });
   }
 
   /**

typings/index.d.ts

@@ -2119,7 +2119,11 @@ export class WebhookClient extends WebhookMixin(BaseClient) {
     message: MessageResolvable,
     options: string | MessagePayload | WebhookEditMessageOptions,
   ): Promise<APIMessage>;
+  public fetchMessage(message: Snowflake, options?: WebhookFetchMessageOptions): Promise<APIMessage>;
+  /* tslint:disable:unified-signatures */
+  /** @deprecated */
   public fetchMessage(message: Snowflake, cache?: boolean): Promise<APIMessage>;
+  /* tslint:enable:unified-signatures */
   public send(options: string | MessagePayload | WebhookMessageOptions): Promise<APIMessage>;
 }
 
@@ -2825,12 +2829,16 @@ export function WebhookMixin<T>(Base?: Constructable<T>): Constructable<T & Webh
 export interface PartialWebhookFields {
   id: Snowflake;
   readonly url: string;
-  deleteMessage(message: MessageResolvable | APIMessage | '@original'): Promise<void>;
+  deleteMessage(message: MessageResolvable | APIMessage | '@original', threadId?: Snowflake): Promise<void>;
   editMessage(
     message: MessageResolvable | '@original',
     options: string | MessagePayload | WebhookEditMessageOptions,
   ): Promise<Message | APIMessage>;
+  fetchMessage(message: Snowflake | '@original', options?: WebhookFetchMessageOptions): Promise<Message | APIMessage>;
+  /* tslint:disable:unified-signatures */
+  /** @deprecated */
   fetchMessage(message: Snowflake | '@original', cache?: boolean): Promise<Message | APIMessage>;
+  /* tslint:enable:unified-signatures */
   send(options: string | MessagePayload | WebhookMessageOptions): Promise<Message | APIMessage>;
 }
 
@@ -4790,9 +4798,14 @@ export interface WebhookEditData {
 
 export type WebhookEditMessageOptions = Pick<
   WebhookMessageOptions,
-  'content' | 'embeds' | 'files' | 'allowedMentions' | 'components' | 'attachments'
+  'content' | 'embeds' | 'files' | 'allowedMentions' | 'components' | 'attachments' | 'threadId'
 >;
 
+export interface WebhookFetchMessageOptions {
+  cache?: boolean;
+  threadId?: Snowflake;
+}
+
 export interface WebhookMessageOptions extends Omit<MessageOptions, 'reply'> {
   username?: string;
   avatarURL?: string;