/**
* Copyright (C) 2009-2013 FoundationDB, LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.foundationdb.rest;
import com.foundationdb.rest.resources.ResourceHelper;
import com.foundationdb.server.Quote;
import com.foundationdb.server.error.ErrorCode;
import com.foundationdb.server.error.NoSuchRoutineException;
import com.foundationdb.server.error.NoSuchTableException;
import com.foundationdb.util.AkibanAppender;
import com.fasterxml.jackson.core.JsonParseException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.StreamingOutput;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.nio.charset.Charset;
import java.util.HashMap;
import java.util.Map;
public class RestResponseBuilder {
public interface BodyGenerator {
public void write(PrintWriter writer) throws Exception;
}
private static final Charset UTF8 = Charset.forName("UTF-8");
private static final Map<Class,Response.Status> EXCEPTION_STATUS_MAP = buildExceptionStatusMap();
private static final Logger LOG = LoggerFactory.getLogger(RestResponseBuilder.class);
private final HttpServletRequest request;
private final boolean isJsonp;
private BodyGenerator outputGenerator;
private String outputBody;
private String jsonp;
private int status;
private MediaType type;
public RestResponseBuilder(HttpServletRequest request, String jsonp) {
this.request = request;
this.jsonp = jsonp;
this.isJsonp = jsonp != null;
this.status = Response.Status.OK.getStatusCode();
}
public static RestResponseBuilder forRequest(HttpServletRequest request) {
return new RestResponseBuilder(request, request.getParameter(ResourceHelper.JSONP_ARG_NAME));
}
public RestResponseBuilder status(Response.Status status) {
this.status = status.getStatusCode();
return this;
}
public RestResponseBuilder type(MediaType type) {
this.type = type;
return this;
}
public RestResponseBuilder body(String outputBody) {
this.outputBody = outputBody;
this.outputGenerator = null;
return this;
}
public RestResponseBuilder body(ErrorCode code, String message) {
body(formatErrorWithJsonp(code.getFormattedValue(), message));
return this;
}
public RestResponseBuilder body(BodyGenerator outputGenerator) {
this.outputBody = null;
this.outputGenerator = outputGenerator;
return this;
}
public Response build() {
if(outputBody == null && outputGenerator == null && jsonp == null) {
status(Response.Status.NO_CONTENT);
}
if (isJsonp) {
status(Response.Status.OK);
}
Response.ResponseBuilder builder;
if (this.status == Response.Status.NO_CONTENT.getStatusCode()) {
builder = Response.status(status).type((MediaType)null);
} else {
builder = Response.status(status).entity(createStreamingOutput());
}
if(isJsonp) {
builder.type(ResourceHelper.APPLICATION_JAVASCRIPT_TYPE);
} else if (type != null) {
builder.type(type);
}
return builder.build();
}
public static void formatJsonError(StringBuilder builder, String code, String message, String note) {
builder.append("{\"code\":\"");
builder.append(code);
builder.append("\", \"message\":\"");
Quote.JSON_QUOTE.append(AkibanAppender.of(builder), message);
if (note != null) {
builder.append("\", \"note\":\"");
Quote.JSON_QUOTE.append(AkibanAppender.of(builder), note);
}
builder.append("\"}");
}
private String formatErrorWithJsonp(String code, String message) {
StringBuilder builder = new StringBuilder();
if(isJsonp) {
builder.append(jsonp);
builder.append('(');
}
formatJsonError(builder, code, message, null);
if(isJsonp) {
builder.append(')');
}
builder.append('\n');
return builder.toString();
}
public WebApplicationException wrapException(Throwable e) {
final ErrorCode code = ErrorCode.getCodeForRESTException(e);
Response.Status status = EXCEPTION_STATUS_MAP.get(e.getClass());
if(status == null) {
status = Response.Status.CONFLICT;
}
code.logAtImportance(
LOG, "Exception from request(method: {}, url: {}, params: {})",
request.getMethod(), request.getRequestURL(), request.getQueryString(),
e
);
String exMsg = (e.getMessage() != null) ? e.getMessage() : e.getClass().getName();
return new WebApplicationException(
Response.status(status)
.entity(formatErrorWithJsonp(code.getFormattedValue(), exMsg))
.type(isJsonp ? ResourceHelper.APPLICATION_JAVASCRIPT_TYPE : MediaType.APPLICATION_JSON_TYPE)
.build()
);
}
private StreamingOutput createStreamingOutput() {
return new StreamingOutput() {
@Override
public void write(OutputStream output) {
try {
PrintWriter writer = new PrintWriter(new OutputStreamWriter(output, UTF8), false);
if(isJsonp) {
writer.write(jsonp);
writer.write('(');
}
if(outputGenerator != null) {
outputGenerator.write(writer);
} else if(outputBody != null) {
writer.write(outputBody);
}
if(isJsonp) {
writer.write(')');
}
writer.write('\n');
writer.flush();
writer.close();
} catch(Throwable t) {
throw wrapException(t);
}
}
};
}
private static Map<Class, Response.Status> buildExceptionStatusMap() {
Map<Class, Response.Status> map = new HashMap<>();
map.put(NoSuchTableException.class, Response.Status.NOT_FOUND);
map.put(NoSuchRoutineException.class, Response.Status.NOT_FOUND);
map.put(JsonParseException.class, Response.Status.BAD_REQUEST);
return map;
}
}