This changeset moves common checks from driver implementations into base
package. The Base type can be embedded in a driver implementation, ensuring
that incoming arguments are checked for validity.
Signed-off-by: Stephen J Day <stephen.day@docker.com>
We now also have a storagedriver error variable for identifying
api calls that are not implemented by drivers (the URLFor method
is not implemented by either the filesystem or inmemory drivers)
v4auth will default to true and if the frankfurt (eu-central-1) region
is selected with v4auth set to false explicitly, the driver will error
out upon initialization.
The secure flag will be true by default and will change the
s3 endpoint of the region to http instead of https when selected as false.
The main benefits of running with secure being false is that it apparently
has a roughly 33% performance boost (even on pure data transfer, not only
connection setup which is what I would have expected).
Note that the README currently contains details about the secure parameter which is part of a
separate pull request. I feel confident adding it here since I am certain we will eventually add
the secure parameter. Also note that encrypt now defaults to true and rootdirectory defaults to
the empty string.
This requires some discussion of how we will handle errors due to network problems
and after further changes in that direction some more stress testing. There is also an
upcomming commit implementing zero fill on WriteStream when offset is greater than
the current size of the file.
The packages causing build errors are being disabled for now to let us split up
the work in the different driver implementations without blocking integration
into the main branch. The s3 and azure implementations need some effort to add
Stat support. The ipc package needs that work plus some care around hanging
send calls.
This change brings the storagedriver API in line with the Go standard library's
use of int64 for offsets. The main benefit is simplicity in interfacing with
the io library reducing the number of type conversions in simple code.
This only works for a specific whitelist of error types, which is
currently all errors in the storagedriver package.
Also improves storagedriver tests to enforce proper error types are
returned
Custom storage drivers can register a factory to create the driver by
name, similar to the database/sql package's Register and Open
factory.Create returns an in-process driver if registered or an IPC
driver if one can be found, erroring otherwise
This standardizes parameter passing for creation of storage drivers
Also adds documentation for storagedriver package and children
