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/* * Copyright 2011 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.social.soundcloud.api.impl; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.springframework.http.HttpStatus; import org.springframework.http.client.ClientHttpResponse; import org.springframework.social.InternalServerErrorException; import org.springframework.social.InvalidAuthorizationException; import org.springframework.social.NotAuthorizedException; import org.springframework.social.OperationNotPermittedException; import org.springframework.social.ResourceNotFoundException; import org.springframework.social.ServerDownException; import org.springframework.social.UncategorizedApiException; import org.springframework.web.client.DefaultResponseErrorHandler; import com.fasterxml.jackson.core.JsonFactory; import com.fasterxml.jackson.core.JsonParseException; import com.fasterxml.jackson.core.type.TypeReference; import com.fasterxml.jackson.databind.ObjectMapper; /** * Subclass of {@link DefaultResponseErrorHandler} that handles errors from SoundCloud's * API, interpreting them into appropriate exceptions. * @author Michael Lavelle */ class SoundCloudErrorHandler extends DefaultResponseErrorHandler { @Override public void handleError(ClientHttpResponse response) throws IOException { List<Map<String, String>> errorDetails = extractErrorDetailsFromResponse(response); if (errorDetails == null) { handleUncategorizedError(response, errorDetails); } handleSoundCloudError(response.getStatusCode(), errorDetails); // if not otherwise handled, do default handling and wrap with UncategorizedApiException handleUncategorizedError(response, errorDetails); } @Override public boolean hasError(ClientHttpResponse response) throws IOException { if (super.hasError(response)) { return true; } // only bother checking the body for errors if we get past the default error check String content = readFully(response.getBody()); return content.startsWith("{\"errors\":"); } private boolean isMessageContainingText(List<String> messages, String text) { for (String message : messages) { return message.contains(text); } return false; } private boolean isMessageStartsWithText(List<String> messages, String text) { for (String message : messages) { return message.startsWith(text); } return false; } private String constructMessage(List<String> messages) { return messages.toString(); } /** * Examines the error data returned from SoundCloud and throws the most applicable exception. * @param errorDetails a Map containing an "error_message" */ void handleSoundCloudError(HttpStatus statusCode, List<Map<String, String>> errorDetailsList) { // Can't trust the type to be useful. It's often OAuthException, even for things not OAuth-related. // Can rely only on the message (which itself isn't very consistent). List<String> messages = new ArrayList<String>(); for (Map<String, String> errorDetails : errorDetailsList) { String message = errorDetails.get("error_message"); messages.add(message); } String message = constructMessage(messages); if (statusCode == HttpStatus.OK) { } else if (statusCode == HttpStatus.BAD_REQUEST) { throw new ResourceNotFoundException("soundcloud", message); } else if (statusCode == HttpStatus.NOT_FOUND) { throw new ResourceNotFoundException("soundcloud", message); } else if (statusCode == HttpStatus.UNAUTHORIZED) { if (isMessageStartsWithText(messages, "invalid_token")) { handleInvalidAccessToken(message); } throw new NotAuthorizedException("soundcloud", message); } else if (statusCode == HttpStatus.FORBIDDEN) { throw new OperationNotPermittedException("soundcloud", message); } else if (statusCode == HttpStatus.INTERNAL_SERVER_ERROR) { throw new InternalServerErrorException("soundcloud", message); } else if (statusCode == HttpStatus.SERVICE_UNAVAILABLE) { throw new ServerDownException("soundcloud", message); } } private void handleInvalidAccessToken(String message) { if (message.contains("invalid_token")) { throw new InvalidAuthorizationException("soundcloud", "An invalid token was supplied"); } else { throw new InvalidAuthorizationException("soundcloud", message); } } private void handleUncategorizedError(ClientHttpResponse response, List<Map<String, String>> errorDetails) { try { super.handleError(response); } catch (Exception e) { if (errorDetails != null) { String m = ""; throw new UncategorizedApiException("soundcloud", m, e); } else { throw new UncategorizedApiException("soundcloud", "No error details from SoundCloud", e); } } } /* * Attempts to extract SoundCloud error details from the response. * Returns null if the response doesn't match the expected JSON error response. */ @SuppressWarnings("unchecked") private List<Map<String, String>> extractErrorDetailsFromResponse(ClientHttpResponse response) throws IOException { ObjectMapper mapper = new ObjectMapper(new JsonFactory()); List<String> authenticateHeaders = response.getHeaders().get("Www-Authenticate"); String authenticateHeader = authenticateHeaders == null || authenticateHeaders.size() == 0 ? null : authenticateHeaders.get(0); String json = null; if (authenticateHeader != null) { json = "{" + authenticateHeader.replace('=', ':').replace("OAuth realm", "\"OAuth realm\"") .replace("error", "\"error\"") + "}"; try { Map<String, String> responseMap = mapper.<Map<String, String>>readValue(json, new TypeReference<Map<String, String>>() { }); List<Map<String, String>> errorsList = new ArrayList<Map<String, String>>(); if (responseMap.containsKey("error")) { Map<String, String> errorMap = new HashMap<String, String>(); errorMap.put("error_message", responseMap.get("error")); errorsList.add(errorMap); return errorsList; } } catch (JsonParseException e) { return null; } } else { json = readFully(response.getBody()); try { Map<String, Object> responseMap = mapper.<Map<String, Object>>readValue(json, new TypeReference<Map<String, Object>>() { }); if (responseMap.containsKey("errors")) { return (List<Map<String, String>>) responseMap.get("errors"); } else { return null; } } catch (JsonParseException e) { return null; } } return null; } private String readFully(InputStream in) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(in)); StringBuilder sb = new StringBuilder(); while (reader.ready()) { sb.append(reader.readLine()); } return sb.toString(); } }