aws-snap-io

用于实现 AWS 快照的读写库。该库目前不提供异步读写实现，也没有在读取过程中使用并行方式读取多个块。可以使用稀疏缓存层，这样多个读取不会下载同一块多次。

支持的文件系统

使用 Coldsnap 通过并行方式复制整个快照。

read_snapshot

Test tool to read a number of bytes from a given offset in a snapshot. This requires that you have already setup your AWS credentials and region. This application is for testing and example only. Note this tool/lib does not support concurrent reads from a snapshot. Look at Coldsnap for that functionality

Usage: read_snapshot.exe [OPTIONS] --snapshot <SNAPSHOT> --offset <OFFSET> --length <LENGTH>

Options:
  -s, --snapshot <SNAPSHOT>  The name of the snapshot to read from
  -o, --offset <OFFSET>      The offset in the snapshot to start reading from
  -l, --length <LENGTH>      The length in bytes to read
      --logging <LOGGING>    The logging level to use [default: Info] [possible values: Off, Error, Warn, Info, Debug, Trace]
  -h, --help                 Print help information
  -V, --version              Print version information

示例

aws-snap-io$ ./target/release/examples/read_snapshot --snapshot snap-0acad277e952dfa05 --offset 330010624 --length 1091 | xxd -r -p
Files originating with or related to Casablanca v2.6.0, a "Microsoft project for cloud-based client-server communication in native code using a modern asynchronous C++ API design. This project aims to help C++ developers connect to and interact with services." See https://github.com/Microsoft/cpprestsdk. This material is licensed under the terms of the Apache Software License v2.0 (see https://github.com/Microsoft/cpprestsdk/blob/master/license.txt), which state:

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