[REQ] Provide more meaningful error messages

[toddysm]

What kind of request is this?

Improvement of existing experience

What is your request or suggestion?

Adding more user context to the error messages that Copa returns helps troubleshoot unattended use of the tool. For example, I made a mistake to call copa with wrong reference to the image using digest like this:

myrepo/myimage:sha:<digest>

And the returned error was:

level=error msg="unexpected: TagNameOnly did create Tagged ref"
Error: unexpected: TagNameOnly did create Tagged ref

The above error doesn't help the user to understand what the problem is and leaves her wondering.

Providing full context how the tool is invoked and what part of the invocation was wrong would be much friendlier.

Are you willing to submit PRs to contribute to this feature request?

• Yes, I am willing to implement it.

[prakrit55]

hey @sozercan, I would like to give it a try

[prakrit55]

hello @sozercan when I tried with
copa patch -r nginx.1.21.6.json -i library/nginx:sha256:2bcabc23b45489fb0885d69a06ba1d648aeda973fae7bb981bafbb884165e514, its giving Error: invalid reference format. Is this an expected behavior ??

[ashnamehrotra]

Hi @prakrit55 the correct format would be copa patch -r nginx.1.21.6.json -i library/nginx:1.21.6@sha256:2bcabc23b45489fb0885d69a06ba1d648aeda973fae7bb981bafbb884165e514. Created issue #624 to add documentation for this.