无法从我的 Google App Engine Servlet (Java) 将对象存储在我的 Google Cloud Storage 中答案

【问题标题】：Cannot store objects in my Google Cloud Storage from my Google App Engine Servlet (Java)无法从我的 Google App Engine Servlet (Java) 将对象存储在我的 Google Cloud Storage 中
【发布时间】：2017-06-19 11:56:51
【问题描述】：

我正在使用我的 App Engine 来允许应用上传文件。该文件是在 HTTP POST 中接收的，我正在尝试将其存储在 Google Storage 中。

我的服务器代码；

GcsFileOptions instance = GcsFileOptions.getDefaultInstance();
GcsFilename fileName = new GcsFilename("my-bucket", "file.dat");
GcsOutputChannel outputChannel;

log.info("Saving " + fileName + " to " + instance);

outputChannel = gcsService.createOrReplace(fileName, instance);
copy(req.getInputStream(), Channels.newOutputStream(outputChannel));

中间的Log条目产生；

com.my.app.Servlet: Saving GcsFilename(my-bucket, file.dat) to GcsFileOptions [userMetadata={}]

这会导致异常；

com.google.appengine.tools.cloudstorage.RetriesExhaustedException: RetryHelper(5.644 s, 10 attempts, com.google.appengine.tools.cloudstorage.GcsServiceImpl$1@1af95fcc): Too many failures, giving up
    at com.google.appengine.tools.cloudstorage.RetryHelper.doRetry(RetryHelper.java:127)
    at com.google.appengine.tools.cloudstorage.RetryHelper.runWithRetries(RetryHelper.java:166)
    at com.google.appengine.tools.cloudstorage.RetryHelper.runWithRetries(RetryHelper.java:156)
    at com.google.appengine.tools.cloudstorage.GcsServiceImpl.createOrReplace(GcsServiceImpl.java:70)
    at com.my.app.Servlet.saveFile(Servlet.java:128)
    at com.my.app.Servlet.doPost(Servlet.java:107)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
... <Cut by submitter>
Caused by: java.io.IOException: java.lang.NullPointerException
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService$BlobStorageAdapter.getInstance(LocalRawGcsService.java:186)
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService$BlobStorageAdapter.access$000(LocalRawGcsService.java:109)
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService.ensureInitialized(LocalRawGcsService.java:194)
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService.beginObjectCreation(LocalRawGcsService.java:249)
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService.beginObjectCreation(LocalRawGcsService.java:92)
    at com.google.appengine.tools.cloudstorage.GcsServiceImpl$1.call(GcsServiceImpl.java:74)
    at com.google.appengine.tools.cloudstorage.GcsServiceImpl$1.call(GcsServiceImpl.java:70)
    at com.google.appengine.tools.cloudstorage.RetryHelper.doRetry(RetryHelper.java:108)
    ... 34 more
Caused by: java.lang.NullPointerException
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService$BlobStorageAdapter.<init>(LocalRawGcsService.java:123)
    at com.google.appengine.tools.cloudstorage.dev.LocalRawGcsService$BlobStorageAdapter.getInstance(LocalRawGcsService.java:184) 
    ... 41 more

【问题讨论】：

标签： java google-app-engine google-cloud-storage

【解决方案1】：

解决了。这个问题（在类似的情况下）已经在这里回答了：How to fetch the file list from gcs?

【讨论】：