-package de.juplo.facebook.errors;
-
-
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.nio.charset.Charset;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.http.HttpHeaders;
-import org.springframework.http.HttpStatus;
-import org.springframework.http.client.ClientHttpResponse;
-import org.springframework.util.FileCopyUtils;
-import org.springframework.web.client.ResponseErrorHandler;
-
-
-
-/**
- * Error-Handler for error-messages from the Facebook Graph-API.
- * <p>
- * This error-handler handels responses withe the HTTP-status code
- * {@code 400 BAD REQUEST}. It tries to extract and parse the error-message
- * from the HTTP-body. Successfully extracted and parsed messages are mapped
- * to a hierarchy of exceptions, that reflects the hierarchy of the error-
- * codes and -types.
- * <p>
- * If the HTTP-status-code of the response is not {@code 400 BAD REQUEST} or
- * the HTTP-body could not be extracted or parsed, this error-handler
- * delegates the handling to its parent.
- *
- * @see <a href="https://developers.facebook.com/docs/graph-api/using-graph-api/v2.5#errors">Graph-API Documentation</a>
- * @see <a href="http://fbdevwiki.com/wiki/Error_codes">Inofficial Wiki For Facebook-Developers</a>
- * @author Kai Moritz
- */
-public class GraphApiErrorHandler implements ResponseErrorHandler
-{
- private final static Logger LOG =
- LoggerFactory.getLogger(GraphApiErrorHandler.class);
-
- private final ResponseErrorHandler parent;
-
-
- public GraphApiErrorHandler(ResponseErrorHandler errorHandler)
- {
- this.parent = errorHandler;
- }
-
-
- @Override
- public boolean hasError(ClientHttpResponse response) throws IOException
- {
- return
- HttpStatus.Series.CLIENT_ERROR.equals(response.getStatusCode().series())
- || this.parent.hasError(response);
- }
-
- @Override
- public void handleError(final ClientHttpResponse response) throws IOException
- {
- GraphApiErrorHandler.handleError(parent, response);
- }
-
- public static void handleError(
- final ResponseErrorHandler parent,
- final ClientHttpResponse response
- )
- throws
- IOException
- {
- if (response.getBody() == null)
- {
- // There is no body to interpret in the HTTP-message
- LOG.warn("Could not convert the response into an exception, because there is no message-body.");
- parent.handleError(response);
- return;
- }
-
- final byte[] body = FileCopyUtils.copyToByteArray(response.getBody());
- GraphApiException error;
-
- try
- {
- error = GraphApiException.create(response.getStatusCode(), response.getHeaders(), body);
- if (LOG.isInfoEnabled())
- LOG.info("error-response: {}", new String(body, Charset.forName("UTF-8")));
- }
- catch (Exception e)
- {
- // The body of the HTTP-message could not be parsed.
- // Let the parent error-handler try to handle the response.
-
- LOG.warn(
- "Could not convert the response into an exception, " +
- "because the body is unparsable: error={}, body={}",
- e.toString(),
- new String(body, Charset.forName("UTF-8"))
- );
-
- // To do so, we have to wrap the original response to fill in
- // the buffered body, if needed
- ClientHttpResponse buffered = new ClientHttpResponse()
- {
- @Override
- public HttpStatus getStatusCode() throws IOException
- {
- return response.getStatusCode();
- }
-
- @Override
- public synchronized InputStream getBody() throws IOException
- {
- return new ByteArrayInputStream(body);
- }
-
- @Override
- public HttpHeaders getHeaders()
- {
- return response.getHeaders();
- }
-
- @Override
- public String getStatusText() throws IOException
- {
- return response.getStatusText();
- }
-
- @Override
- public void close()
- {
- response.close();
- }
-
- @Override
- public int getRawStatusCode() throws IOException
- {
- return response.getRawStatusCode();
- }
- };
-
- parent.handleError(buffered);
- return;
- }
-
- throw error;
- }
-}