aws s3 android sdk,兼容S3 SDK-Android
SDK-Android
概述
您可以使用Android SDK管理互盟云对象存储，可从https://github.com/aws/aws-sdk-android 下载Android Source Code
操作
由于android sdk用chunk 方式进行传输，并且把chunk-signature放置在body中，oss不支持这种case；sdk中支持的参数 S3ClientOptions.builder.disableChunkedEncoding在判断的时候并没有采用，因而需要更深层次的hack，需要继承AWSS3V4Signer.java并且覆盖原始的processRequestPayload(计算payload的签名并放在body的开头)和calculateContentHash(长度包含签名部分)，代码如下：
package com.amazonaws.demo.s3transferutility;
import com.amazonaws.AmazonClientException;
import com.amazonaws.Request;
import com.amazonaws.services.s3.Headers;
import com.amazonaws.services.s3.internal.AWSS3V4Signer;
import com.amazonaws.util.BinaryUtils;
import java.io.IOException;
import java.io.InputStream;
public class HmAWSS3V4Signerextends AWSS3V4Signer{
@Override
protectedvoid processRequestPayload(Request> request, HeaderSigningResult headerSigningResult){
}
@Override
protected String calculateContentHash(Request> request){
request.addHeader("x-amz-content-sha256", "required");
final String contentLength =
request.getHeaders().get(Headers.CONTENT_LENGTH);
final long originalContentLength;
if (contentLength !=null) {
originalContentLength = Long.parseLong(contentLength);
}else { /**
* "Content-Length" header could be missing if the caller is
* uploading a stream without setting Content-Length in
* ObjectMetadata. Before using sigv4, we rely on HttpClient to
* add this header by using BufferedHttpEntity when creating the
* HttpRequest object. But now, we need this information
* immediately for the signing process, so we have to cache the
* stream here.
*/
try {
originalContentLength = getContentLength(request);
}catch (IOException e) {
throw new AmazonClientException(
"Cannot get the content-lenght of the request content.",e);
}
}
request.addHeader("x-amz-decoded-content-length",Long.toString(originalContentLength));
final InputStream payloadStream = getBinaryRequestPayloadStream(request);
payloadStream.mark(-1);
final String contentSha256 = BinaryUtils.toHex(hash(payloadStream));
try {
payloadStream.reset();
}catch (final IOException e) {
throw new AmazonClientException(
"Unable to reset stream after calculating AWS4 signature", e);
}
return contentSha256;
}
private long getContentLength(Request> request) throws IOException{
InputStream content = request.getContent();
if (!content.markSupported()) {
throw new AmazonClientException("Failed to get content length");
}
final int DEFAULT_BYTE_LENGTH = 4096;
long contentLength = 0;
byte[ ] tmp =new byte[DEFAULT_BYTE_LENGTH];
int read;
content.mark(-1);
while ((read = content.read(tmp)) != -1) {
contentLength += read;
}
content.reset();
return contentLength;
}
}
然后利用SignerFactory.registerSigner("HmAWSS3V4Signer", HmAWSS3V4Signer.class)替换标准签名，实现代码如下：
SignerFactory.registerSigner("HmAWSS3V4Signer", HmAWSS3V4Signer.class);
System.setProperty(SDKGlobalConfiguration.ENABLE_S3_SIGV4_SYSTEM_PROPERTY, "true");
ClientConfiguration config = new ClientConfiguration();
config.setProtocol(Protocol.HTTP);
config.setSignerOverride("HmAWSS3V4Signer");
sS3Client = new AmazonS3Client(getCredProvider(context.getApplicationContext()), config);
sS3Client.setEndpoint("https://oss-cn-shenzhen.humengyun.com");
S3ClientOptions options = S3ClientOptions.builder()
.disableChunkedEncoding()
.setPayloadSigningEnabled(true)
.build();
sS3Client.setS3ClientOptions(options);