AWS Java SDK使用元數據進行上載時出錯

Question

我正在嘗試將文件上傳到S3容器，在進行上傳之前，我正在設置文件的元數據。 上傳失敗，並顯示簽名不匹配的錯誤。 以下是我使用的代碼：

public URL send(File f, HashMap<String,String> metadata, String type) throws Exception {
    String path = type+"/"+f.getName();

    InitiateMultipartUploadRequest req = new InitiateMultipartUploadRequest(container, secretKey).withKey(path);
    req.setCannedACL(CannedAccessControlList.AuthenticatedRead);

    if (metadata != null) {
        ObjectMetadata objectMetadata = new ObjectMetadata();
        Set<String> keys = metadata.keySet();
        Iterator<String> i = keys.iterator();
        while (i.hasNext()) {
            String key = i.next();
            objectMetadata.addUserMetadata(key, metadata.get(key));
        }
        req.setObjectMetadata(objectMetadata);
    }


    InitiateMultipartUploadResult res = s3client.initiateMultipartUpload(req);

    String uploadId = res.getUploadId();
    long fileSize = f.length();
    //check the size doesn't exceed max limit
    if (fileSize > MAX_OBJ_SIZE) {
        throw new Exception("Object size exceeds repository limit");
    }
    long chunkSize = 1024 * 1024 * 16;
    int chunks = (int) (fileSize/chunkSize + 2);
    List<PartETag> chunkList = new ArrayList<PartETag>();
    long pos = 0; 
    try {
        for (int i = 1; i < chunks; i++) {

            if ((chunks -i) < 2) {
                chunkSize = fileSize - pos;
            }

            UploadPartRequest upReq = new UploadPartRequest()
                    .withBucketName(container).withKey(path)
                    .withUploadId(uploadId).withPartNumber(i)
                    .withFileOffset(pos).withFile(f)
                    .withPartSize(chunkSize);

            PartETag pTag = null;
            // repeat the upload until it succeeds.
            boolean repeat;  
            do {
                repeat = false;  // reset switch
                try {
                    // Upload part and add response to our list.
                    pTag =   s3client.uploadPart(upReq).getPartETag(); 
                } 
                catch (Exception ex) {
                    repeat = true; // repeat
                }
            } while (repeat);

            chunkList.add(pTag);
            pos = pos + chunkSize;
        }
        CompleteMultipartUploadRequest compl = new CompleteMultipartUploadRequest(
                container, secretKey, uploadId, chunkList).withKey(path);
        CompleteMultipartUploadResult  complRes = s3client.completeMultipartUpload(compl);
        return new URL(URLDecoder.decode(complRes.getLocation(), "UTF-8"));
    }
    catch (Exception ex) {
        s3client.abortMultipartUpload(new AbortMultipartUploadRequest(container, 
                secretKey, uploadId));
        throw new Exception("File upload error: "+ex.toString());
    }
}

以下是我得到的錯誤：

 com.amazonaws.services.s3.model.AmazonS3Exception: Status Code: 403, AWS Service: Amazon S3, AWS Request ID: 0805716BBD0662AB, AWS Error Code: SignatureDoesNotMatch, AWS Error Message: The request signature we calculated does not match the signature you provided. Check your key and signing method., S3 Extended Request ID: wNAzUyrLZgWCazZFe3KpMHO0uh0FM5FF7fiwBzN1A2YDEYS5hKZBYh5nWSjIhnhG
at com.amazonaws.http.AmazonHttpClient.handleErrorResponse(AmazonHttpClient.java:767)
at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:414)
at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:228)
at com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:3316)
at com.amazonaws.services.s3.AmazonS3Client.initiateMultipartUpload(AmazonS3Client.java:2401)
at net.timbusproject.storage.awss3.S3Client.send(S3Client.java:134)

發生錯誤的S3Client.java中的第134行是：

 InitiateMultipartUploadResult res = s3client.initiateMultipartUpload(req);

如果我沒有附加任何元數據，上傳工作正常。 即，如果我評論下面的行，上傳工作：

 req.setObjectMetadata(objectMetadata);

我無法弄清楚設置元數據時請求失敗的原因。 我錯過了上傳過程中的任何步驟嗎？

Answer 1

我能夠通過URL編碼元數據鍵和值來解決這個問題。

objectMetadata.addUserMetadata(URLEncoder.encode(key, "UTF-8"), URLEncoder.encode(metadata.get(key),"UTF-8"));

顯然，元數據似乎有一些違反AWS調用的違規字符。 此解決方法將允許上載完成而不會出現錯誤，並且還會更新元數據，但字符串仍然是url編碼的，這可能會在以后出現問題。