import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
-import java.util.List;
+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.http.converter.HttpMessageConverter;
-import org.springframework.http.converter.HttpMessageNotReadableException;
-import org.springframework.security.oauth2.client.http.OAuth2ErrorHandler;
import org.springframework.util.FileCopyUtils;
-import org.springframework.web.client.HttpMessageConverterExtractor;
-import org.springframework.web.client.RestClientException;
-import org.springframework.web.client.RestTemplate;
+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.
*
- * @author kai
+ * @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 extends OAuth2ErrorHandler
+public class GraphApiErrorHandler implements ResponseErrorHandler
{
- private final OAuth2ErrorHandler errorHandler;
- private List<HttpMessageConverter<?>> messageConverters =
- new RestTemplate().getMessageConverters();
+ private final static Logger LOG =
+ LoggerFactory.getLogger(GraphApiErrorHandler.class);
-
- public GraphApiErrorHandler(OAuth2ErrorHandler errorHandler)
- {
- super(null);
- this.errorHandler = errorHandler;
- }
+ private final ResponseErrorHandler parent;
- /**
- * @param messageConverters the messageConverters to set
- */
- @Override
- public void setMessageConverters(
- List<HttpMessageConverter<?>> messageConverters
- )
+ public GraphApiErrorHandler(ResponseErrorHandler errorHandler)
{
- this.messageConverters = messageConverters;
- errorHandler.setMessageConverters(messageConverters);
+ this.parent = errorHandler;
}
+
@Override
public boolean hasError(ClientHttpResponse response) throws IOException
{
return
HttpStatus.Series.CLIENT_ERROR.equals(response.getStatusCode().series())
- || this.errorHandler.hasError(response);
+ || this.parent.hasError(response);
}
@Override
public void handleError(final ClientHttpResponse response) throws IOException
{
- if (!HttpStatus.Series.CLIENT_ERROR.equals(response.getStatusCode().series()))
+ if (!HttpStatus.BAD_REQUEST.equals(response.getStatusCode()))
+ {
+ // We will only handle 400 BAD REQUEST
+ LOG.debug("ignoring response with status-code {}.", response.getStatusCode());
+ parent.handleError(response);
+ return;
+ }
+
+
+ if (response.getBody() == null)
{
- // We should only care about 400 level errors. Ex: A 500 server error shouldn't
- // be an oauth related error.
- errorHandler.handleError(response);
+ // 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;
}
- else
+
+ final byte[] body = FileCopyUtils.copyToByteArray(response.getBody());
+ GraphApiException error;
+
+ try
{
- // Need to use buffered response because input stream may need to be consumed multiple times.
- ClientHttpResponse bufferedResponse = new ClientHttpResponse()
- {
- private byte[] lazyBody;
+ error = GraphApiException.create(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: {}", body);
+ // 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
{
@Override
public synchronized InputStream getBody() throws IOException
{
- if (lazyBody == null) {
- InputStream bodyStream = response.getBody();
- if (bodyStream != null) {
- lazyBody = FileCopyUtils.copyToByteArray(bodyStream);
- }
- else {
- lazyBody = new byte[0];
- }
- }
- return new ByteArrayInputStream(lazyBody);
+ return new ByteArrayInputStream(body);
}
@Override
}
};
-
- HttpMessageConverterExtractor<GraphApiException> extractor =
- new HttpMessageConverterExtractor<>(
- GraphApiException.class,
- messageConverters
- );
-
- try
- {
- GraphApiException body = extractor.extractData(bufferedResponse);
- if (body != null)
- {
- // If we can get an OAuth2Exception already from the body, it is likely
- // to have more information than the header does, so just re-throw it
- // here.
- body.setHttpErrorCode(response.getRawStatusCode());
- throw body;
- }
- }
- catch (RestClientException|HttpMessageNotReadableException e)
- {
- // ignore
- }
-
- errorHandler.handleError(bufferedResponse);
+ parent.handleError(buffered);
+ return;
}
+
+ throw error;
}
}
projects / facebook-utils / blobdiff