add webhook functionality

src/constants/discord.ts

@@ -77,6 +77,8 @@ export const endpoints = {
   GUILD_VANITY_URL: (id: string) => `${GUILDS_BASE(id)}/vanity-url`,
   GUILD_WEBHOOKS: (id: string) => `${GUILDS_BASE(id)}/webhooks`,
 
+  WEBHOOK: (id: string, token: string) => `${baseEndpoints.BASE_URL}/webhooks/${id}/${token}`,
+
   // User endpoints
   USER_AVATAR: (id: string, icon: string) =>
     `${baseEndpoints.CDN_URL}/avatars/${id}/${icon}`,

src/handlers/webhook.ts

@@ -0,0 +1,102 @@
+import {
+  WebhookCreateOptions,
+  WebhookPayload,
+  ExecuteWebhookOptions,
+} from "../types/webhook.ts";
+import { botHasChannelPermissions } from "../utils/permissions.ts";
+import { Permissions } from "../types/permission.ts";
+import { Errors } from "../types/errors.ts";
+import { RequestManager } from "../module/requestManager.ts";
+import { endpoints } from "../constants/discord.ts";
+import { createMessage } from "../structures/message.ts";
+import { MessageCreateOptions } from "../types/message.ts";
+import { urlToBase64 } from "../utils/utils.ts";
+
+/** Create a new webhook. Requires the MANAGE_WEBHOOKS permission. Returns a webhook object on success. Webhook names follow our naming restrictions that can be found in our Usernames and Nicknames documentation, with the following additional stipulations:
+*
+* Webhook names cannot be: 'clyde'
+*/
+export async function createWebhook(
+  channelID: string,
+  options: WebhookCreateOptions,
+) {
+  if (
+    !botHasChannelPermissions(
+      channelID,
+      [Permissions.MANAGE_WEBHOOKS],
+    )
+  ) {
+    throw new Error(Errors.MISSING_MANAGE_WEBHOOKS);
+  }
+
+  if (
+    // Specific usernames that discord does not allow
+    options.name === "clyde" ||
+    // Character limit checks. [...] checks are because of js unicode length handling
+    [...options.name].length < 2 || [...options.name].length > 32
+  ) {
+    throw new Error(Errors.INVALID_WEBHOOK_NAME);
+  }
+
+  return RequestManager.post(
+    endpoints.CHANNEL_WEBHOOKS(channelID),
+    {
+      ...options,
+      avatar: options.avatar ? await urlToBase64(options.avatar) : undefined,
+    },
+  ) as Promise<WebhookPayload>;
+}
+
+export async function executeWebhook(
+  webhookID: string,
+  webhookToken: string,
+  options: ExecuteWebhookOptions,
+) {
+  if (!options.content && !options.file && !options.embeds) {
+    throw new Error(Errors.INVALID_WEBHOOK_OPTIONS);
+  }
+
+  if (options.embeds && options.embeds.length > 10) {
+    options.embeds.splice(10);
+  }
+
+  if (options.mentions) {
+    if (options.mentions.users?.length) {
+      if (options.mentions.parse.includes("users")) {
+        options.mentions.parse = options.mentions.parse.filter((p) =>
+          p !== "users"
+        );
+      }
+
+      if (options.mentions.users.length > 100) {
+        options.mentions.users = options.mentions.users.slice(0, 100);
+      }
+    }
+
+    if (options.mentions.roles?.length) {
+      if (options.mentions.parse.includes("roles")) {
+        options.mentions.parse = options.mentions.parse.filter((p) =>
+          p !== "roles"
+        );
+      }
+
+      if (options.mentions.roles.length > 100) {
+        options.mentions.roles = options.mentions.roles.slice(0, 100);
+      }
+    }
+  }
+
+  const result = await RequestManager.post(
+    `${endpoints.WEBHOOK(webhookID, webhookToken)}${
+      options.wait ? "?wait=true" : ""
+    }`,
+    {
+      ...options,
+      allowed_mentions: options.mentions,
+      avatar_url: options.avatar_url,
+    },
+  );
+  if (!options.wait) return;
+
+  return createMessage(result as MessageCreateOptions);
+}

src/types/errors.ts

@@ -28,4 +28,6 @@ export enum Errors {
   REQUEST_UNKNOWN_ERROR = "REQUEST_UNKNOWN_ERROR",
   BOTS_HIGHEST_ROLE_TOO_LOW = "BOTS_HIGHEST_ROLE_TOO_LOW",
   CHANNEL_NOT_IN_GUILD = "CHANNEL_NOT_IN_GUILD",
+  INVALID_WEBHOOK_NAME = "INVALID_WEBHOOK_NAME",
+  INVALID_WEBHOOK_OPTIONS = "INVALID_WEBHOOK_OPTIONS",
 }

src/types/webhook.ts

@@ -0,0 +1,61 @@
+import { UserPayload } from "./guild.ts";
+import { Embed } from "./message.ts";
+
+export interface WebhookPayload {
+  /** The id of the webhook */
+  id: string;
+  /** The type of the webhook */
+  type: WebhookType;
+  /** The guild id this webhook is for */
+  guild_id?: string;
+  /** The channel id this webhook is for */
+  channel_id: string;
+  /** The user this webhook was created by(not returned when getting a webhook with its token) */
+  user?: UserPayload;
+  /** The default name of the webhook */
+  name?: string;
+  /** The default avatar of the webhook */
+  avatar?: string;
+  /** The secure token of the webhook(returned for Incoming Webhooks) */
+  token?: string;
+}
+
+export enum WebhookType {
+  /** Incoming Webhooks can post messages to channels with a generated token */
+  INCOMING = 1,
+  /** Channel Follower Webhooks are internal webhooks used with Channel Following to post new messages into channels */
+  CHANNEL_FOLLOWER = 2,
+}
+
+export interface WebhookCreateOptions {
+  /** Name of the webhook (1-80 characters) */
+  name: string;
+  /** Image url for avatar image for the default webhook avatar */
+  avatar?: string;
+}
+
+export interface ExecuteWebhookOptions {
+  /** waits for server confirmation of message send before response, and returns the created message body (defaults to false; when false a message that is not saved does not return an error) */
+  wait?: boolean;
+  /** the message contents (up to 2000 characters) */
+  content?: string;
+  /** override the default username of the webhook */
+  username?: string;
+  /** override the default avatar of the webhook*/
+  avatar_url?: string;
+  /** true if this is a TTS message */
+  tts?: boolean;
+  /** file contents	the contents of the file being sent	one of content, file, embeds */
+  file?: { blob: unknown; name: string };
+  /** array of up to 10 embed objects	embedded rich content. */
+  embeds?: Embed[];
+  /** allowed mentions for the message */
+  mentions?: {
+    /** An array of allowed mention types to parse from the content. */
+    parse: ("roles" | "users" | "everyone")[];
+    /** Array of role_ids to mention (Max size of 100) */
+    roles?: string[];
+    /** Array of user_ids to mention (Max size of 100) */
+    users?: string[];
+  };
+}