Backgroundoras.Copy is consisted of several different operations. To add more context to the returned error, current implementation is to wrap a description string over the error, e.g. when resolving the source artifact fails, below string will be added to wrap the original error:
Problem
This method imposes below challenges when processing the obtained error:
1) string context are hard to process: taking the above error as an example, it's hard to extract out the added context failed to resolve $srcRef out elegantly from caller side
2) lack information of where the error happens: an error might happens on source target or destination target, it's not reflected in the added context
Solution
Adding a structured error type for error returned by oras.Copy like below
type CopyError struct {
// represents the failing operation, e.g. resolve
Op string
// represents where it fails
On string // enumerable string, source or dest
// Inner error
Err error
}
Background
oras.Copy
is consisted of several different operations. To add more context to the returned error, current implementation is to wrap a description string over the error, e.g. when resolving the source artifact fails, below string will be added to wrap the original error:https://github.com/oras-project/oras-go/blob/f29607202d5a72ee5325171bf7fc6698ccb4e45f/copy.go#L138
Problem This method imposes below challenges when processing the obtained error: 1) string context are hard to process: taking the above error as an example, it's hard to extract out the added context
failed to resolve $srcRef
out elegantly from caller side 2) lack information of where the error happens: an error might happens on source target or destination target, it's not reflected in the added contextSolution Adding a structured error type for error returned by
oras.Copy
like below