/*
* Copyright 2010-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Portions copyright 2006-2009 James Murty. Please see LICENSE.txt
* for applicable license terms and NOTICE.txt for applicable notices.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file 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 com.amazonaws.services.s3.internal;
import com.amazonaws.Request;
import com.amazonaws.services.s3.Headers;
import com.amazonaws.services.s3.model.ResponseHeaderOverrides;
import com.amazonaws.util.StringUtils;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
/**
* Utilities useful for REST/HTTP S3Service implementations.
*/
public class RestUtils {
/**
* The set of request parameters which must be included in the canonical
* string to sign.
*/
private static final List<String> SIGNED_PARAMETERS = Arrays.asList(new String[] {
"acl", "torrent", "logging", "location", "policy", "requestPayment", "versioning",
"versions", "versionId", "notification", "uploadId", "uploads", "partNumber",
"website", "delete", "lifecycle", "tagging", "cors", "restore", "accelerate",
ResponseHeaderOverrides.RESPONSE_HEADER_CACHE_CONTROL,
ResponseHeaderOverrides.RESPONSE_HEADER_CONTENT_DISPOSITION,
ResponseHeaderOverrides.RESPONSE_HEADER_CONTENT_ENCODING,
ResponseHeaderOverrides.RESPONSE_HEADER_CONTENT_LANGUAGE,
ResponseHeaderOverrides.RESPONSE_HEADER_CONTENT_TYPE,
ResponseHeaderOverrides.RESPONSE_HEADER_EXPIRES,
});
/**
* Calculate the canonical string for a REST/HTTP request to S3. When
* expires is non-null, it will be used instead of the Date header.
*/
public static <T> String makeS3CanonicalString(String method, String resource,
Request<T> request, String expires)
{
StringBuilder buf = new StringBuilder();
buf.append(method + "\n");
// Add all interesting headers to a list, then sort them. "Interesting"
// is defined as Content-MD5, Content-Type, Date, and x-amz-
Map<String, String> headersMap = request.getHeaders();
SortedMap<String, String> interestingHeaders = new TreeMap<String, String>();
if (headersMap != null && headersMap.size() > 0) {
Iterator<Map.Entry<String, String>> headerIter = headersMap.entrySet().iterator();
while (headerIter.hasNext()) {
Map.Entry<String, String> entry = headerIter.next();
String key = entry.getKey();
String value = entry.getValue();
if (key == null)
continue;
String lk = StringUtils.lowerCase(key.toString());
// Ignore any headers that are not particularly interesting.
if (lk.equals("content-type") || lk.equals("content-md5") || lk.equals("date") ||
lk.startsWith(Headers.AMAZON_PREFIX))
{
interestingHeaders.put(lk, value);
}
}
}
// Remove default date timestamp if "x-amz-date" is set.
if (interestingHeaders.containsKey(Headers.S3_ALTERNATE_DATE)) {
interestingHeaders.put("date", "");
}
// Use the expires value as the timestamp if it is available. This
// trumps both the default
// "date" timestamp, and the "x-amz-date" header.
if (expires != null) {
interestingHeaders.put("date", expires);
}
// These headers require that we still put a new line in after them,
// even if they don't exist.
if (!interestingHeaders.containsKey("content-type")) {
interestingHeaders.put("content-type", "");
}
if (!interestingHeaders.containsKey("content-md5")) {
interestingHeaders.put("content-md5", "");
}
// Any parameters that are prefixed with "x-amz-" need to be included
// in the headers section of the canonical string to sign
for (Map.Entry<String, String> parameter : request.getParameters().entrySet()) {
if (parameter.getKey().startsWith("x-amz-")) {
interestingHeaders.put(parameter.getKey(), parameter.getValue());
}
}
// Add all the interesting headers (i.e.: all that startwith x-amz- ;-))
for (Iterator<Map.Entry<String, String>> i = interestingHeaders.entrySet().iterator(); i
.hasNext();) {
Map.Entry<String, String> entry = i.next();
String key = entry.getKey();
String value = entry.getValue();
if (key.startsWith(Headers.AMAZON_PREFIX)) {
buf.append(key).append(':');
if (value != null) {
buf.append(value);
}
} else if (value != null) {
buf.append(value);
}
buf.append("\n");
}
// Add all the interesting parameters
buf.append(resource);
String[] parameterNames = request.getParameters().keySet().toArray(
new String[request.getParameters().size()]);
Arrays.sort(parameterNames);
char separator = '?';
for (String parameterName : parameterNames) {
// Skip any parameters that aren't part of the canonical signed
// string
if (SIGNED_PARAMETERS.contains(parameterName) == false)
continue;
buf.append(separator);
buf.append(parameterName);
String parameterValue = request.getParameters().get(parameterName);
if (parameterValue != null) {
buf.append("=").append(parameterValue);
}
separator = '&';
}
return buf.toString();
}
}