feat(GuildPreview): implement support for "preview" endpoint (#3965)

* feat(GuildPreview): method — fetchGuildPreview

* feat(GuildPreview): structure — GuildPreview

* feat(GuildPreview): update typings

* fix(GuildPreview): remove typedef for Features — already exists

* refactor(GuildPreview): update JSDocs & method

* feat(GuildPreview): implement DiscoverySplash function

* fix(GuildPreview): description & error handling for id

* fix(GuildPreview): misleading description, assign emojis correctly

* feat(GuildPreview): func DisplaySplash & GuildPreviewEmoji interface

* fix(Typings): satisfy TSLint

* fix(GuildPreview): toJSON - returns a value now

* feat(GuildPreview): add fetchPreview method on instance of Guild

* feat(GuildPreview): update typings

* fix: missing client constructor

* fix: typo in typings

* feat(BaseEmoji): implement BaseEmoji — parent for emoji instances

* feat(BaseEmoji): refactor - GuildEmoji extends BaseEmoji now

* feat(BaseEmoji): refactor - adjust emojis prop to BaseEmoji instance

* feat(BaseEmoji): not documented fully - GuildPreviewEmoji

* feat(BaseEmoji): update typings

* fix: remove duplicate typing properties - inherited

* fix: remove redundant methods & properties - inherited / already set

* fix: let -> const

* fix: typings - put BaseEmoji after BaseClient

* fix: remove _clone method  - redundant

* refactor(GuildPreview): emojis should be a collection

* refactor: rename base class, move relevant props there and expose roles

* fix(GuildPreview): update emojis in _patch

* fix(Typings): remove empty line, add Client#fetchGuildPreview

* feat: export GuildPreview

* fix(Typings): add GuildPreview#discoverSplash, icon, and splash

Co-authored-by: LxveFades <twitchisadeck@gmail.com>
Co-authored-by: Crawl <icrawltogo@gmail.com>
Co-authored-by: SpaceEEC <spaceeec@yahoo.com>

src/structures/BaseGuildEmoji.js

@@ -0,0 +1,58 @@
+'use strict';
+
+const Emoji = require('./Emoji');
+
+/**
+ * Parent class for {@link GuildEmoji} and {@link GuildPreviewEmoji}.
+ * @extends {Emoji}
+ */
+class BaseGuildEmoji extends Emoji {
+  constructor(client, data, guild) {
+    super(client, data);
+
+    /**
+     * The guild this emoji is a part of
+     * @type {Guild|GuildPreview}
+     */
+    this.guild = guild;
+
+    /**
+     * Array of role ids this emoji is active for
+     * @name BaseGuildEmoji#_roles
+     * @type {Snowflake[]}
+     * @private
+     */
+    Object.defineProperty(this, '_roles', { value: [], writable: true });
+
+    this._patch(data);
+  }
+
+  _patch(data) {
+    if (data.name) this.name = data.name;
+
+    /**
+     * Whether or not this emoji requires colons surrounding it
+     * @type {boolean}
+     * @name GuildEmoji#requiresColons
+     */
+    if (typeof data.require_colons !== 'undefined') this.requiresColons = data.require_colons;
+
+    /**
+     * Whether this emoji is managed by an external service
+     * @type {boolean}
+     * @name GuildEmoji#managed
+     */
+    if (typeof data.managed !== 'undefined') this.managed = data.managed;
+
+    /**
+     * Whether this emoji is available
+     * @type {boolean}
+     * @name GuildEmoji#available
+     */
+    if (typeof data.available !== 'undefined') this.available = data.available;
+
+    if (data.roles) this._roles = data.roles;
+  }
+}
+
+module.exports = BaseGuildEmoji;

src/structures/Guild.js

@@ -2,6 +2,7 @@
 
 const Base = require('./Base');
 const GuildAuditLogs = require('./GuildAuditLogs');
+const GuildPreview = require('./GuildPreview');
 const Integration = require('./Integration');
 const Invite = require('./Invite');
 const VoiceRegion = require('./VoiceRegion');
@@ -709,6 +710,17 @@ class Guild extends Base {
       });
   }
 
+  /**
+   * Obtains a guild preview for this guild from Discord, only available for public guilds.
+   * @returns {Promise<GuildPreview>}
+   */
+  fetchPreview() {
+    return this.client.api
+      .guilds(this.id)
+      .preview.get()
+      .then(data => new GuildPreview(this.client, data));
+  }
+
   /**
    * Fetches the vanity url invite code to this guild.
    * Resolves with a string matching the vanity url invite code, not the full url.

src/structures/GuildEmoji.js

@@ -1,65 +1,29 @@
 'use strict';
 
-const Emoji = require('./Emoji');
+const BaseGuildEmoji = require('./BaseGuildEmoji');
 const { Error } = require('../errors');
 const GuildEmojiRoleManager = require('../managers/GuildEmojiRoleManager');
 const Permissions = require('../util/Permissions');
 
 /**
  * Represents a custom emoji.
- * @extends {Emoji}
+ * @extends {BaseGuildEmoji}
  */
-class GuildEmoji extends Emoji {
+class GuildEmoji extends BaseGuildEmoji {
   /**
+   * @name GuildEmoji
+   * @kind constructor
+   * @memberof GuildEmoji
    * @param {Client} client The instantiating client
    * @param {Object} data The data for the guild emoji
    * @param {Guild} guild The guild the guild emoji is part of
    */
-  constructor(client, data, guild) {
-    super(client, data);
 
-    /**
-     * The guild this emoji is part of
-     * @type {Guild}
-     */
-    this.guild = guild;
-
-    /**
-     * The ID of this emoji
-     * @type {Snowflake}
-     * @name GuildEmoji#id
-     */
-
-    this._roles = [];
-    this._patch(data);
-  }
-
-  _patch(data) {
-    if (data.name) this.name = data.name;
-
-    /**
-     * Whether or not this emoji requires colons surrounding it
-     * @type {boolean}
-     * @name GuildEmoji#requiresColons
-     */
-    if (typeof data.require_colons !== 'undefined') this.requiresColons = data.require_colons;
-
-    /**
-     * Whether this emoji is managed by an external service
-     * @type {boolean}
-     * @name GuildEmoji#managed
-     */
-    if (typeof data.managed !== 'undefined') this.managed = data.managed;
-
-    /**
-     * Whether this emoji is available
-     * @type {boolean}
-     * @name GuildEmoji#available
-     */
-    if (typeof data.available !== 'undefined') this.available = data.available;
-
-    if (data.roles) this._roles = data.roles;
-  }
+  /**
+   * The guild this emoji is part of
+   * @type {Guild}
+   * @name GuildEmoji#guild
+   */
 
   _clone() {
     const clone = super._clone();

src/structures/GuildPreview.js

@@ -0,0 +1,157 @@
+'use strict';
+
+const Base = require('./Base');
+const GuildPreviewEmoji = require('./GuildPreviewEmoji');
+const Collection = require('../util/Collection');
+
+/**
+ * Represents the data about the guild any bot can preview, connected to the specified public guild.
+ * @extends {Base}
+ */
+class GuildPreview extends Base {
+  constructor(client, data) {
+    super(client);
+
+    if (!data) return;
+
+    this._patch(data);
+  }
+
+  /**
+   * Builds the public guild with the provided data.
+   * @param {*} data The raw data of the public guild
+   * @private
+   */
+  _patch(data) {
+    /**
+     * The id of this public guild
+     * @type {string}
+     */
+    this.id = data.id;
+
+    /**
+     * The name of this public guild
+     * @type {string}
+     */
+    this.name = data.name;
+
+    /**
+     * The icon of this public guild
+     * @type {?string}
+     */
+    this.icon = data.icon;
+
+    /**
+     * The splash icon of this public guild
+     * @type {?string}
+     */
+    this.splash = data.splash;
+
+    /**
+     * The discovery splash icon of this public guild
+     * @type {?string}
+     */
+    this.discoverySplash = data.discovery_splash;
+
+    /**
+     * An array of enabled guild features
+     * @type {Features[]}
+     */
+    this.features = data.features;
+
+    /**
+     * The approximate count of members in this public guild
+     * @type {number}
+     */
+    this.approximateMemberCount = data.approximate_member_count;
+
+    /**
+     * The approximate count of online members in this public guild
+     * @type {number}
+     */
+    this.approximatePresenceCount = data.approximate_presence_count;
+
+    /**
+     * The description for this public guild
+     * @type {?string}
+     */
+    this.description = data.description;
+
+    if (!this.emojis) {
+      /**
+       * Collection of emojis belonging to this public guild
+       * @type {Collection<Snowflake, GuildPreviewEmoji>}
+       */
+      this.emojis = new Collection();
+    } else {
+      this.emojis.clear();
+    }
+    for (const emoji of data.emojis) {
+      this.emojis.set(emoji.id, new GuildPreviewEmoji(this.client, emoji, this));
+    }
+  }
+
+  /**
+   * The URL to this public guild's splash.
+   * @param {ImageURLOptions} [options={}] Options for the Image URL
+   * @returns {?string}
+   */
+  splashURL({ format, size } = {}) {
+    if (!this.splash) return null;
+    return this.client.rest.cdn.Splash(this.id, this.splash, format, size);
+  }
+
+  /**
+   * The URL to this public guild's discovery splash.
+   * @param {ImageURLOptions} [options={}] Options for the Image URL
+   * @returns {?string}
+   */
+  discoverySplashURL({ format, size } = {}) {
+    if (!this.discoverySplash) return null;
+    return this.client.rest.cdn.DiscoverySplash(this.id, this.discoverySplash, format, size);
+  }
+
+  /**
+   * The URL to this public guild's icon.
+   * @param {ImageURLOptions} [options={}] Options for the Image URL
+   * @returns {?string}
+   */
+  iconURL({ format, size, dynamic } = {}) {
+    if (!this.icon) return null;
+    return this.client.rest.cdn.Icon(this.id, this.icon, format, size, dynamic);
+  }
+
+  /**
+   * Fetches this public guild.
+   * @returns {Promise<GuildPreview>}
+   */
+  fetch() {
+    return this.client.api
+      .guilds(this.id)
+      .preview.get()
+      .then(data => {
+        this._patch(data);
+        return this;
+      });
+  }
+
+  /**
+   * When concatenated with a string, this automatically returns the guild's name instead of the Guild object.
+   * @returns {string}
+   * @example
+   * // Logs: Hello from My Guild!
+   * console.log(`Hello from ${previewGuild}!`);
+   */
+  toString() {
+    return this.name;
+  }
+
+  toJSON() {
+    const json = super.toJSON();
+    json.iconURL = this.iconURL();
+    json.splashURL = this.splashURL();
+    return json;
+  }
+}
+
+module.exports = GuildPreview;

src/structures/GuildPreviewEmoji.js

@@ -0,0 +1,26 @@
+'use strict';
+
+const BaseGuildEmoji = require('./BaseGuildEmoji');
+
+/**
+ * Represents an instance of an emoji belonging to a public guild obtained through Discord's preview endpoint.
+ * @extends {BaseGuildEmoji}
+ */
+class GuildPreviewEmoji extends BaseGuildEmoji {
+  /**
+   * The public guild this emoji is part of
+   * @type {GuildPreview}
+   * @name GuildPreviewEmoji#guild
+   */
+
+  /**
+   * Set of roles this emoji is active for
+   * @type {Set<Snowflake>}
+   * @readonly
+   */
+  get roles() {
+    return new Set(this._roles);
+  }
+}
+
+module.exports = GuildPreviewEmoji;