Add last.fm provider

.github/ISSUE_TEMPLATE/2_bug_provider.yml

@@ -63,6 +63,7 @@ body:
         - "Frontegg"
         - "Keycloak"
         - "Kinde"
+        - "Last.fm"
         - "Line"
         - "LinkedIn"
         - "Logto"

packages/core/src/providers/lastfm.ts

@@ -0,0 +1,189 @@
+/**
+ * <div class="provider" style={{backgroundColor: "#000", display: "flex", justifyContent: "space-between", color: "#fff", padding: 16}}>
+ * <span>Built-in <b>Last.fm</b> integration.</span>
+ * <a href="https://www.last.fm/">
+ *   <img style={{display: "block"}} src="https://authjs.dev/img/providers/lastfm.svg" height="48" />
+ * </a>
+ * </div>
+ *
+ * @module providers/lastfm
+ */
+import { createHash } from "crypto";
+
+import type { TokenSet } from "../types.js";
+import type { OAuthConfig, OAuthUserConfig } from "./index.js";
+
+export interface LastfmSignatureParams {
+  method: string;
+  token: string;
+  api_key: string;
+  api_secret: string;
+}
+
+export interface LastfmSession {
+  session: {
+    name: string;
+    key: string;
+    subscriber: string;
+  };
+}
+
+export interface LastfmProfileImage {
+  size: "small" | "medium" | "large" | "extralarge";
+  "#text": string;
+}
+
+export interface LastfmProfile extends Record<string, any> {
+  user: {
+    name: string;
+    age: string;
+    subscriber: string;
+    realname: string;
+    bootstrap: string;
+    playcount: string;
+    artist_count: string;
+    playlists: string;
+    track_count: string;
+    album_count: string;
+    image: LastfmProfileImage[];
+    registered: {
+      unixtime: string;
+      "#text": number;
+    };
+    country: string;
+    gender: string;
+    url: string;
+    type: string;
+  };
+}
+
+function generateApiSig({
+  method,
+  token,
+  api_key,
+  api_secret,
+}: LastfmSignatureParams): string {
+  const raw = `api_key${api_key}method${method}token${token}${api_secret}`;
+
+  return createHash("md5").update(raw).digest("hex");
+}
+
+/**
+ * Add Last.fm login to your page.
+ *
+ * ### Setup
+ *
+ * #### Callback URL
+ * ```
+ * https://example.com/api/auth/callback/lastfm
+ * ```
+ *
+ * #### Configuration
+ *```ts
+ * import { Auth } from "@auth/core"
+ * import Lastfm from "@auth/core/providers/lastfm"
+ *
+ * const request = new Request(origin)
+ * const response = await Auth(request, {
+ *   providers: [
+ *     Lastfm({
+ *       clientId: LASTFM_API_KEY,
+ *       clientSecret: LASTFM_SHARED_SECRET,
+ *     }),
+ *   ],
+ * })
+ * ```
+ *
+ * ### Resources
+ *
+ * - [Last.fm OAuth documentation](https://www.last.fm/api/webauth)
+ * - [Last.fm app console](https://www.last.fm/api/accounts)
+ *
+ * ### Notes
+ *
+ * By default, Auth.js assumes that the Last.fm provider is
+ * based on the [OAuth 2](https://www.rfc-editor.org/rfc/rfc6749.html) specification.
+ *
+ * :::tip
+ *
+ * The Last.fm provider comes with a [default configuration](https://github.com/nextauthjs/next-auth/blob/main/packages/core/src/providers/lastfm.ts).
+ * To override the defaults for your use case, check out [customizing a built-in OAuth provider](https://authjs.dev/guides/configuring-oauth-providers).
+ *
+ * :::
+ *
+ * :::info **Disclaimer**
+ *
+ * If you think you found a bug in the default configuration, you can [open an issue](https://authjs.dev/new/provider-issue).
+ *
+ * Auth.js strictly adheres to the specification and it cannot take responsibility for any deviation from
+ * the spec by the provider. You can open an issue, but if the problem is non-compliance with the spec,
+ * we might not pursue a resolution. You can ask for more help in [Discussions](https://authjs.dev/new/github-discussions).
+ *
+ * :::
+ */
+export default function Lastfm<P extends LastfmSession>(
+  options: OAuthUserConfig<P>
+): OAuthConfig<P> {
+  return {
+    id: "lastfm",
+    name: "Last.fm",
+    type: "oauth",
+    authorization: {
+      url: "http://www.last.fm/api/auth",
+      params: { api_key: options.clientId },
+    },
+    token: {
+      request: async ({ provider, params }) => {
+        const token = params.token;
+
+        const apiSig = generateApiSig({
+          method: "auth.getSession",
+          token,
+          api_key: provider.clientId!,
+          api_secret: provider.clientSecret!,
+        });
+
+        const res = await fetch(
+          `https://ws.audioscrobbler.com/2.0/?method=auth.getSession&api_key=${provider.clientId}&token=${token}&api_sig=${apiSig}&format=json`
+        );
+
+        const data = (await res.json()) as LastfmSession;
+
+        return {
+          tokens: {
+            access_token: data.session.key,
+            token_type: "bearer",
+            scope: "",
+            expires_at: null,
+          } satisfies TokenSet,
+        };
+      },
+    },
+    userinfo: {
+      request: async ({ provider, tokens }) => {
+        const res = await fetch(
+          `https://ws.audioscrobbler.com/2.0/?method=user.getInfo&api_key=${provider.clientId}&sk=${tokens.access_token}&format=json`
+        );
+
+        const user = (await res.json()) as LastfmProfile;
+
+        return {
+          session: {
+            name: user.name,
+            key: tokens.access_token,
+            subscriber: user.subscriber,
+          },
+        };
+      },
+    },
+    profile(profile) {
+      return {
+        id: profile.session.key,
+        name: profile.session.name,
+        email: null,
+        image: null,
+      };
+    },
+    options,
+  };
+}