Device Authorization

npx @better-auth/cli login

const { data } = await authClient.device.code({
  client_id: "your-client-id",
  scope: "openid profile email",
});

if (data) {
  console.log(`Please visit: ${data.verification_uri}`);
  console.log(`And enter code: ${data.user_code}`);
}

let pollingInterval = 5; // Start with 5 seconds
const pollForToken = async () => {
  const { data, error } = await authClient.device.token({
    grant_type: "urn:ietf:params:oauth:grant-type:device_code",
    device_code,
    client_id: yourClientId,
    fetchOptions: {
      headers: {
        "user-agent": `My CLI`,
      },
    },
  });

  if (data?.access_token) {
    console.log("Authorization successful!");
  } else if (error) {
    switch (error.error) {
      case "authorization_pending":
        // Continue polling
        break;
      case "slow_down":
        pollingInterval += 5;
        break;
      case "access_denied":
        console.error("Access was denied by the user");
        return;
      case "expired_token":
        console.error("The device code has expired. Please try again.");
        return;
      default:
        console.error(`Error: ${error.error_description}`);
        return;
    }
    setTimeout(pollForToken, pollingInterval * 1000);
  }
};

pollForToken();

export default function DeviceAuthorizationPage() {
  const [userCode, setUserCode] = useState("");
  const [error, setError] = useState(null);
  
  const handleSubmit = async (e) => {
    e.preventDefault();
    
    try {
      // Format the code: remove dashes and convert to uppercase
      const formattedCode = userCode.trim().replace(/-/g, "").toUpperCase();

      // Check if the code is valid using GET /device endpoint
      const response = await authClient.device.deviceVerify({
        query: { user_code: formattedCode },
      });
      
      if (response.data) {
        // Redirect to approval page
        window.location.href = `/device/approve?user_code=${formattedCode}`;
      }
    } catch (err) {
      setError("Invalid or expired code");
    }
  };
  
  return (
    <form onSubmit={handleSubmit}>
      <input
        type="text"
        value={userCode}
        onChange={(e) => setUserCode(e.target.value)}
        placeholder="Enter device code (e.g., ABCD-1234)"
        maxLength={12}
      />
      <button type="submit">Continue</button>
      {error && <p>{error}</p>}
    </form>
  );
}

export default function DeviceApprovalPage() {
  const { user } = useAuth(); // Must be authenticated
  const searchParams = useSearchParams();
  const userCode = searchParams.get("userCode");
  const [isProcessing, setIsProcessing] = useState(false);
  
  const handleApprove = async () => {
    setIsProcessing(true);
    try {
      await authClient.device.deviceApprove({
        userCode: userCode,
      });
      // Show success message
      alert("Device approved successfully!");
      window.location.href = "/";
    } catch (error) {
      alert("Failed to approve device");
    }
    setIsProcessing(false);
  };
  
  const handleDeny = async () => {
    setIsProcessing(true);
    try {
      await authClient.device.deviceDeny({
        userCode: userCode,
      });
      alert("Device denied");
      window.location.href = "/";
    } catch (error) {
      alert("Failed to deny device");
    }
    setIsProcessing(false);
  };

  if (!user) {
    // Redirect to login if not authenticated
    window.location.href = `/login?redirect=/device/approve?user_code=${userCode}`;
    return null;
  }
  
  return (
    <div>
      <h2>Device Authorization Request</h2>
      <p>A device is requesting access to your account.</p>
      <p>Code: {userCode}</p>
      
      <button onClick={handleApprove} disabled={isProcessing}>
        Approve
      </button>
      <button onClick={handleDeny} disabled={isProcessing}>
        Deny
      </button>
    </div>
  );
}

deviceAuthorization({
  validateClient: async (clientId) => {
    // Check if client is authorized
    const client = await db.oauth_clients.findOne({ id: clientId });
    return client && client.allowDeviceFlow;
  },
  
  onDeviceAuthRequest: async (clientId, scope) => {
    // Log device authorization requests
    await logDeviceAuthRequest(clientId, scope);
  },
})

deviceAuthorization({
  generateDeviceCode: async () => {
    // Custom device code generation
    return crypto.randomBytes(32).toString("hex");
  },
  
  generateUserCode: async () => {
    // Custom user code generation
    // Default uses: ABCDEFGHJKLMNPQRSTUVWXYZ23456789
    // (excludes 0, O, 1, I to avoid confusion)
    const charset = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789";
    let code = "";
    for (let i = 0; i < 8; i++) {
      code += charset[Math.floor(Math.random() * charset.length)];
    }
    return code;
  },
})

import { createAuthClient } from "better-auth/client";
import { deviceAuthorizationClient } from "better-auth/client/plugins";
import open from "open";

const authClient = createAuthClient({
  baseURL: "http://localhost:3000",
  plugins: [deviceAuthorizationClient()],
});

async function authenticateCLI() {
  console.log("🔐 Better Auth Device Authorization Demo");
  console.log("⏳ Requesting device authorization...");
  
  try {
    // Request device code
    const { data, error } = await authClient.device.code({
      client_id: "demo-cli",
      scope: "openid profile email",
    });
    
    if (error || !data) {
      console.error("❌ Error:", error?.error_description);
      process.exit(1);
    }
    
    const {
      device_code,
      user_code,
      verification_uri,
      verification_uri_complete,
      interval = 5,
    } = data;
    
    console.log("\n📱 Device Authorization in Progress");
    console.log(`Please visit: ${verification_uri}`);
    console.log(`Enter code: ${user_code}\n`);
    
    // Open browser with the complete URL
    const urlToOpen = verification_uri_complete || verification_uri;
    if (urlToOpen) {
      console.log("🌐 Opening browser...");
      await open(urlToOpen);
    }
    
    console.log(`⏳ Waiting for authorization... (polling every ${interval}s)`);
    
    // Poll for token
    await pollForToken(device_code, interval);
  } catch (err) {
    console.error("❌ Error:", err.message);
    process.exit(1);
  }
}

async function pollForToken(deviceCode: string, interval: number) {
  let pollingInterval = interval;
  
  return new Promise<void>((resolve) => {
    const poll = async () => {
      try {
        const { data, error } = await authClient.device.token({
          grant_type: "urn:ietf:params:oauth:grant-type:device_code",
          device_code: deviceCode,
          client_id: "demo-cli",
        });
        
        if (data?.access_token) {
          console.log("\n✅ Authorization Successful!");
          console.log("Access token received!");
          
          // Get user session
          const { data: session } = await authClient.getSession({
            fetchOptions: {
              headers: {
                Authorization: `Bearer ${data.access_token}`,
              },
            },
          });
          
          console.log(`Hello, ${session?.user?.name || "User"}!`);
          resolve();
          process.exit(0);
        } else if (error) {
          switch (error.error) {
            case "authorization_pending":
              // Continue polling silently
              break;
            case "slow_down":
              pollingInterval += 5;
              console.log(`⚠️  Slowing down polling to ${pollingInterval}s`);
              break;
            case "access_denied":
              console.error("❌ Access was denied by the user");
              process.exit(1);
              break;
            case "expired_token":
              console.error("❌ The device code has expired. Please try again.");
              process.exit(1);
              break;
            default:
              console.error("❌ Error:", error.error_description);
              process.exit(1);
          }
        }
      } catch (err) {
        console.error("❌ Network error:", err.message);
        process.exit(1);
      }
      
      // Schedule next poll
      setTimeout(poll, pollingInterval * 1000);
    };
    
    // Start polling
    setTimeout(poll, pollingInterval * 1000);
  });
}

// Run the authentication flow
authenticateCLI().catch((err) => {
  console.error("❌ Fatal error:", err);
  process.exit(1);
});