boto initial_multipart_upload 因签名不匹配而失败

我目前正在尝试在互操作模式下将cassandra_snapshotter与云存储一起使用。但是，第一个上传文件的请求因签名不匹配而失败。

做了一个小测试，因为即使是第一个请求也失败了：

import boto
from boto.s3.connection import S3Connection

connection = S3Connection(
    aws_access_key_id='GOOGY',
    aws_secret_access_key='SECRET',
    host='storage.googleapis.com'
)
bucket = connection.get_bucket('foo-cassandra-backups', validate=False)

mp = bucket.initiate_multipart_upload('/g/mnt/cassandra-data2/data/bar/baz-63b205e0618711e7a41cf5e393c7464c/snapshots/20170705150900/manifest.json.lzo')

这失败了：

send: 'POST /g/mnt/cassandra-data2/data/foo/threshold-63b205e0618711e7a41cf5e393c7464c/snapshots/20170705150900/manifest.json.lzo?uploads HTTP/1.1\r\nHost: blubb-cassandra-backups.storage.googleapis.com\r\nAccept-Encoding: identity\r\nDate: Thu, 06 Jul 2017 11:18:46 GMT\r\nContent-Length: 0\r\nAuthorization: AWS BLUBB:F6Ml3vSzDphY7UTGNuf3m+fe19I=\r\nUser-Agent: Boto/2.47.0 Python/2.7.12 Linux/4.4.0-83-generic\r\n\r\n'
reply: 'HTTP/1.1 403 Forbidden\r\n'
header: X-GUploader-UploadID: BLUBB
header: Content-Type: application/xml; charset=UTF-8
header: Content-Length: 447
header: Vary: Origin
header: Date: Thu, 06 Jul 2017 11:18:46 GMT
header: Server: UploadServer
Traceback (most recent call last):
  File "foo.py", line 11, in <module>
    mp = bucket.initiate_multipart_upload('/g/mnt/cassandra-data2/data/foo/threshold-63b205e0618711e7a41cf5e393c7464c/snapshots/20170705150900/manifest.json.lzo')
  File "/usr/local/lib/python2.7/dist-packages/boto/s3/bucket.py", line 1767, in initiate_multipart_upload
    response.status, response.reason, body)
boto.exception.S3ResponseError: S3ResponseError: 403 Forbidden
<?xml version='1.0' encoding='UTF-8'?><Error><Code>SignatureDoesNotMatch</Code><Message>The request signature we calculated does not match the signature you provided. Check your Google secret key and signing method.</Message><StringToSign>POST


Thu, 06 Jul 2017 11:18:46 GMT
/blubb-cassandra-backups/g/mnt/cassandra-data2/data/foo/threshold-63b205e0618711e7a41cf5e393c7464c/snapshots/20170705150900/manifest.json.lzo</StringToSign></Error>

所以我猜在这种情况下 API 不兼容，我在这里相对迷失了如何正确修复它。此外，我想避免对上传器进行大的更改，因为我们还需要部署补丁。

编辑：这是与 boto 2.47 一起使用的，我想这是因为 AWS 需要?uploads参数，但 googles API 不同，因此在签名中不需要它。