fission-s3rofs

README

fission/examples/fission-s3rofs

Example fission (FUSE) File System implementing a read-only File System presentation of an S3 Bucket (with optional Prefix). A clean exit is triggered by sending the process a SIGHUP, SIGINT, or SIGTERM.

Configuration

The program is launched with a single argument specifying the path to a JSON-formatted document with the following structure:

{
  "Verbose"        : false,
  "MountPoint"     : "/mnt",
  "S3AccessKey"    : "test:tester",
  "S3SecretKey"    : "testing",
  "S3Endpoint"     : "http://swift:8080",
  "S3Region"       : "us-east-1",
  "S3Attempts"     : 5,
  "S3Backoff"      : 60,
  "S3Bucket"       : "mybucket",
  "S3Prefix"       : "",
  "FileCacheLines" : 10000,
  "RAMCacheLines"  : 1000,
  "CacheLineSize"  : 1048576
}

If S3AccessKey and/or S3SecretKey are specified as empty strings, their values will be fetched from the ENV.

If FileCacheLines is specified as zero, CacheDirPath's value is ignored. But if FileCacheLines is non-zero, cache lines will spill out of RAM to CacheLineSize sized files in the CacheDirPath specified directory.

Notes

• Not only is the presented File System read-only, it is assumed that the underlying Objects within the Container are unchanging.
• Object names should not contain invalid File basename characters (in particular, no slashes that would suggest a hierarchical directory structure).
• An emulation of the DoGetAttr() / DoLookup() behavior is performed whereby the Attr structure to be returned is computed by means of an Object HEAD response. In particular, the Content-Length in that response is used to initialize the Attr.Size value. The resultant Attr is subsequently cached and there is no cache eviction logic.
• Knowing that the Container contents are unchanging, it would be acceptable to load the Attr.Size values at mount time. But to better emulate a system supporting Attr cache eviction, this mount-time optimization is not performed.