feat: TikTok social provider (#397)

* feat: add TikTok social provider integration with client key support

* chore: lint

* deleted duplicate typeof

* changing verbose of the parameter clientId to client key

* chore: lint

* test: gracefully handle oauth mock server stop

* test: update generic-oauth test server port from 8080 to 8081

---------

Co-authored-by: Bereket Engida <86073083+Bekacru@users.noreply.github.com>
Co-authored-by: Bereket Engida <bekacru@gmail.com>

packages/better-auth/src/oauth2/types.ts

@@ -65,6 +65,11 @@ export type ProviderOptions<Profile extends Record<string, any> = any> = {
 	 * whitelisted in the provider's dashboard.
 	 */
 	redirectURI?: string;
+	/**
+	 * The client key of your application
+	 * Tiktok Social Provider uses this field instead of clientId
+	 */
+	clientKey?: string;
 	/**
 	 * Disable provider from allowing users to sign in
 	 * with this provider with an id token sent from the

packages/better-auth/src/oauth2/validate-authorization-code.ts

@@ -29,6 +29,7 @@ export async function validateAuthorizationCode({
 	body.set("grant_type", "authorization_code");
 	body.set("code", code);
 	codeVerifier && body.set("code_verifier", codeVerifier);
+	options.clientKey && body.set("client_key", options.clientKey);
 	deviceId && body.set("device_id", deviceId);
 	body.set("redirect_uri", options.redirectURI || redirectURI);
 	if (authentication === "basic") {

packages/better-auth/src/social-providers/index.ts

@@ -11,6 +11,7 @@ import { twitter } from "./twitter";
 import { dropbox } from "./dropbox";
 import { linkedin } from "./linkedin";
 import { gitlab } from "./gitlab";
+import { tiktok } from "./tiktok";
 import { reddit } from "./reddit";
 import { roblox } from "./roblox";
 import { z } from "zod";
@@ -28,6 +29,7 @@ export const socialProviders = {
 	dropbox,
 	linkedin,
 	gitlab,
+	tiktok,
 	reddit,
 	roblox,
 	vk,
@@ -38,8 +40,6 @@ export const socialProviderList = Object.keys(socialProviders) as [
 	...(keyof typeof socialProviders)[],
 ];
 
-export type SocialProviderList = typeof socialProviderList;
-
 export const SocialProviderListEnum = z.enum(socialProviderList, {
 	description: "OAuth2 provider to use",
 });
@@ -66,6 +66,9 @@ export * from "./twitter";
 export * from "./dropbox";
 export * from "./linkedin";
 export * from "./gitlab";
+export * from "./tiktok";
 export * from "./reddit";
 export * from "./roblox";
 export * from "./vk";
+
+export type SocialProviderList = typeof socialProviderList;

packages/better-auth/src/social-providers/tiktok.ts

@@ -0,0 +1,182 @@
+import { betterFetch } from "@better-fetch/fetch";
+import type { OAuthProvider, ProviderOptions } from "../oauth2";
+import { validateAuthorizationCode } from "../oauth2";
+
+/**
+ * [More info](https://developers.tiktok.com/doc/tiktok-api-v2-get-user-info/)
+ */
+export interface TiktokProfile extends Record<string, any> {
+	data: {
+		user: {
+			/**
+			 * The unique identification of the user in the current application.Open id
+			 * for the client.
+			 *
+			 * To return this field, add `fields=open_id` in the user profile request's query parameter.
+			 */
+			open_id: string;
+			/**
+			 * The unique identification of the user across different apps for the same developer.
+			 * For example, if a partner has X number of clients,
+			 * it will get X number of open_id for the same TikTok user,
+			 * but one persistent union_id for the particular user.
+			 *
+			 * To return this field, add `fields=union_id` in the user profile request's query parameter.
+			 */
+			union_id?: string;
+			/**
+			 * User's profile image.
+			 *
+			 * To return this field, add `fields=avatar_url` in the user profile request's query parameter.
+			 */
+			avatar_url?: string;
+			/**
+			 * User`s profile image in 100x100 size.
+			 *
+			 * To return this field, add `fields=avatar_url_100` in the user profile request's query parameter.
+			 */
+			avatar_url_100?: string;
+			/**
+			 * User's profile image with higher resolution
+			 *
+			 * To return this field, add `fields=avatar_url_100` in the user profile request's query parameter.
+			 */
+			avatar_large_url: string;
+			/**
+			 * User's profile name
+			 *
+			 * To return this field, add `fields=display_name` in the user profile request's query parameter.
+			 */
+			display_name: string;
+			/**
+			 * User's username.
+			 *
+			 * To return this field, add `fields=username` in the user profile request's query parameter.
+			 */
+			username: string;
+			/** @note Email is currently unsupported by TikTok  */
+			email?: string;
+			/**
+			 * User's bio description if there is a valid one.
+			 *
+			 * To return this field, add `fields=bio_description` in the user profile request's query parameter.
+			 */
+			bio_description?: string;
+			/**
+			 * The link to user's TikTok profile page.
+			 *
+			 * To return this field, add `fields=profile_deep_link` in the user profile request's query parameter.
+			 */
+			profile_deep_link?: string;
+			/**
+			 * Whether TikTok has provided a verified badge to the account after confirming
+			 * that it belongs to the user it represents.
+			 *
+			 * To return this field, add `fields=is_verified` in the user profile request's query parameter.
+			 */
+			is_verified?: boolean;
+			/**
+			 * User's followers count.
+			 *
+			 * To return this field, add `fields=follower_count` in the user profile request's query parameter.
+			 */
+			follower_count?: number;
+			/**
+			 * The number of accounts that the user is following.
+			 *
+			 * To return this field, add `fields=following_count` in the user profile request's query parameter.
+			 */
+			following_count?: number;
+			/**
+			 * The total number of likes received by the user across all of their videos.
+			 *
+			 * To return this field, add `fields=likes_count` in the user profile request's query parameter.
+			 */
+			likes_count?: number;
+			/**
+			 * The total number of publicly posted videos by the user.
+			 *
+			 * To return this field, add `fields=video_count` in the user profile request's query parameter.
+			 */
+			video_count?: number;
+		};
+	};
+	error?: {
+		/**
+		 * The error category in string.
+		 */
+		code?: string;
+		/**
+		 * The error message in string.
+		 */
+		message?: string;
+		/**
+		 * The error message in string.
+		 */
+		log_id?: string;
+	};
+}
+
+export interface TiktokOptions extends ProviderOptions {}
+
+export const tiktok = (options: TiktokOptions) => {
+	return {
+		id: "tiktok",
+		name: "TikTok",
+		createAuthorizationURL({ state, scopes, redirectURI }) {
+			const _scopes = scopes || ["user.info.profile"];
+			options.scope && _scopes.push(...options.scope);
+			return new URL(
+				`https://www.tiktok.com/v2/auth/authorize?scope=${_scopes.join(
+					",",
+				)}&response_type=code&client_key=${options.clientKey}&client_secret=${
+					options.clientSecret
+				}&redirect_uri=${encodeURIComponent(
+					options.redirectURI || redirectURI,
+				)}&state=${state}`,
+			);
+		},
+
+		validateAuthorizationCode: async ({ code, redirectURI }) => {
+			return validateAuthorizationCode({
+				code,
+				redirectURI: options.redirectURI || redirectURI,
+				options,
+				tokenEndpoint: "https://open.tiktokapis.com/v2/oauth/token/",
+			});
+		},
+
+		async getUserInfo(token) {
+			const fields = [
+				"open_id",
+				"avatar_large_url",
+				"display_name",
+				"username",
+			];
+			const { data: profile, error } = await betterFetch<TiktokProfile>(
+				`https://open.tiktokapis.com/v2/user/info/?fields=${fields.join(",")}`,
+				{
+					headers: {
+						authorization: `Bearer ${token.accessToken}`,
+					},
+				},
+			);
+
+			if (error) {
+				return null;
+			}
+
+			return {
+				user: {
+					email: profile.data.user.email || profile.data.user.username,
+					id: profile.data.user.open_id,
+					name: profile.data.user.display_name || profile.data.user.username,
+					image: profile.data.user.avatar_large_url,
+					/** @note Tiktok does not provide emailVerified or even email*/
+					emailVerified: profile.data.user.email ? true : false,
+				},
+				data: profile,
+			};
+		},
+	} satisfies OAuthProvider<TiktokProfile>;
+};