This commit locks down the set of http error codes that will be part of the
inital V2 specification, proposed in docker/docker#9015. The naming order has
been slightly changed and there are few tweaks to ensure all conditions are
captured but this will be set the docker core will be impleemnted against.
To support this, the errors have been moved into an api/errors package. A new
type, ErrorDescriptor, has been defined to centralize the code, message and
definitions used with each type. The information therein can be used to
generate documentation and response code mappings (yet to come...).
In addition to the refactoring that came along with this change, several tests
have been added to ensure serialization round trips are reliable. This allows
better support for using these error types on the client and server side. This
is coupled with some tweaks in the client code to fix issues with error
reporting.
Other fixes in the client include moving client-specific errors out of the base
package and ensuring that we have correct parameters for finishing uploads.
This changeset move the Manifest type into the storage package to make the type
accessible to client and registry without import cycles. The structure of the
manifest was also changed to accuratle reflect the stages of the signing
process. A straw man Manifest.Sign method has been added to start testing this
concept out but will probably be accompanied by the more import
SignedManifest.Verify method as the security model develops.
This is probably the start of a concerted effort to consolidate types across
the client and server portions of the code base but we may want to see how such
a handy type, like the Manifest and SignedManifest, would work in docker core.
Running goroutines with pullLayer are blocked to send error of a
pull operation. If we abort pulling without notify them about
cancelation they will get stucked forever. To avoid this possible
leak cancelCh was introduced. In case of abort we close that channel
to notify other goroutines about cancelation.
A layer can only be pushed/pulled if the layer preceding it by the
length of the push/pull window has been successfully pushed.
An error returned from pushing or pulling any layer will cause the full
operation to be aborted.
These methods rely on an ObjectStore interface, which is meant to
approximate the storage behavior of the docker engine. This is very much
subject to change.
