Class YouTubeAuthHelper

java.lang.Object

uno.anahata.asi.yam.tools.youtube.YouTubeAuthHelper

public class YouTubeAuthHelper
extends Object

Pure Java Google OAuth 2.0 helper managing browser login, authorization code capture, and background access token refresh for YouTube Data API v3.

Operates with zero external OAuth dependencies by utilizing HttpServer for local callback interception, Desktop for system browser launch, and HttpClient for token exchanges.

Author:

anahata

Field Summary

Fields

Modifier and Type	Field	Description
private static String	cachedAccessToken	Cached in-memory access token.
private static final String	CALLBACK_PATH	Local path context where Google OAuth redirects with the authorization code.
static final String	DEFAULT_CLIENT_ID	Default official Anahata ASI Desktop Google Cloud OAuth 2.0 Client ID.
static final String	DEFAULT_CLIENT_SECRET	Default official Anahata ASI Desktop Google Cloud OAuth 2.0 Client Secret.
private static final String	GOOGLE_AUTH_ENDPOINT	Google OAuth 2.0 user authorization endpoint URL.
private static final String	GOOGLE_TOKEN_ENDPOINT	Google OAuth 2.0 token exchange and refresh endpoint URL.
private static final HttpClient	HTTP_CLIENT	Shared HTTP client configured with a 15-second connect timeout for OAuth exchanges.
private static final com.fasterxml.jackson.databind.ObjectMapper	MAPPER	Shared JSON object mapper for deserializing Google token responses.
private static final int	PREFERRED_PORT	Preferred local port for the ephemeral OAuth callback HTTP server.
private static Instant	tokenExpiry	Expiration instant of the cached access token.
private static final String	YOUTUBE_SCOPES	Space-delimited list of YouTube Data API v3 OAuth scopes required for uploading and managing videos.

Constructor Summary

Constructors

Constructor	Description
YouTubeAuthHelper()

Method Summary

Modifier and Type	Method	Description
static String	getValidAccessToken(YouTubeCredentials credentials)	Obtains a valid, unexpired OAuth2 access token.
static YouTubeCredentials	loginInteractive(String clientId, String clientSecret, String playlistId)	Executes the interactive 1-click browser login flow.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

GOOGLE_AUTH_ENDPOINT

private static final String GOOGLE_AUTH_ENDPOINT

Google OAuth 2.0 user authorization endpoint URL.

See Also:

• Constant Field Values

GOOGLE_TOKEN_ENDPOINT

private static final String GOOGLE_TOKEN_ENDPOINT

Google OAuth 2.0 token exchange and refresh endpoint URL.

See Also:

• Constant Field Values

YOUTUBE_SCOPES

private static final String YOUTUBE_SCOPES

Space-delimited list of YouTube Data API v3 OAuth scopes required for uploading and managing videos.

See Also:

• Constant Field Values

DEFAULT_CLIENT_ID

public static final String DEFAULT_CLIENT_ID

Default official Anahata ASI Desktop Google Cloud OAuth 2.0 Client ID.

DEFAULT_CLIENT_SECRET

public static final String DEFAULT_CLIENT_SECRET

Default official Anahata ASI Desktop Google Cloud OAuth 2.0 Client Secret.

PREFERRED_PORT

private static final int PREFERRED_PORT

Preferred local port for the ephemeral OAuth callback HTTP server.

See Also:

• Constant Field Values

CALLBACK_PATH

private static final String CALLBACK_PATH

Local path context where Google OAuth redirects with the authorization code.

See Also:

• Constant Field Values

MAPPER

private static final com.fasterxml.jackson.databind.ObjectMapper MAPPER

Shared JSON object mapper for deserializing Google token responses.

HTTP_CLIENT

private static final HttpClient HTTP_CLIENT

Shared HTTP client configured with a 15-second connect timeout for OAuth exchanges.

cachedAccessToken

private static String cachedAccessToken

Cached in-memory access token.

tokenExpiry

private static Instant tokenExpiry

Expiration instant of the cached access token.

Constructor Details

YouTubeAuthHelper

public YouTubeAuthHelper()

Method Details

getValidAccessToken

public static String getValidAccessToken(YouTubeCredentials credentials)
                                  throws IOException

Obtains a valid, unexpired OAuth2 access token.

If the cached token is expired or missing, it automatically refreshes the token using the stored refresh_token via Google's token endpoint.

Parameters:

credentials - The loaded YouTubeCredentials.

Returns:

A valid OAuth2 bearer access token.

Throws:

IOException - If the token request or refresh fails.

loginInteractive

public static YouTubeCredentials loginInteractive(String clientId,
 String clientSecret,
 String playlistId)
                                           throws Exception

Executes the interactive 1-click browser login flow.

1. Launches a temporary local HTTP server on port 8888.
2. Opens the user's default browser to Google's OAuth consent screen.
3. Intercepts the authorization code from the redirect callback.
4. Exchanges the code for a permanent refresh_token and access token.
5. Saves credentials to ~/.anahata/asi/youtube/credentials.json.

Parameters:

clientId - The Google Cloud OAuth Client ID.

clientSecret - The Google Cloud OAuth Client Secret.

playlistId - The optional default playlist ID.

Returns:

The authenticated and saved YouTubeCredentials.

Throws:

Exception - If authorization or token exchange fails.