Anna Shaleva

This issue was opened as a *discussion*, the result of this issue is the RPC errors proposal (https://github.com/neo-project/proposals/pull/156). Thus, I consider we may close this issue as completed and move...

Just for the record: we've successfully adopted this standard to the NeoGo RPC server in https://github.com/nspcc-dev/neo-go/pull/3063. It works fine in tests and we'll integrate these new error codes into NeoFS...

@roman-khimov, we likely need one more error code: `-400` "Access denied" for those methods that require user's authentication. See the https://github.com/neo-project/neo-modules/pull/815#discussion_r1401568346.

> I guess we need a number for it now. 23? Since this PR is ready to be merged and is in the final stage, I think 23 is good....

Totally agree with Roman, we should adjust this NEP to standardize a single update method. The rest of methods standards should be moved to a separate granular NEPs.

@roman-khimov, let's merge this one also since we've agreed to add DCO to our commits.

Updated.

The following new features may be useful for us: https://cli.urfave.org/v2/examples/flags/#grouping, https://cli.urfave.org/v2/examples/flags/#placeholder-values. For required flags (#2861) we need to combine https://cli.urfave.org/v2/examples/flags/#required-flags with https://cli.urfave.org/v2/examples/flags/#flag-actions to validate the flag is not empty.

Just for the record: migration to Cobra has been declined in favor of Urfave upgrade since there's no issues that can't be resolved with Urfave. The issue with UTF-8 compatibility...

LGTM, we can always iterate through the whole set of blocks stored by `storage.ExecBlock` executable prefix and use `StoreBlock` for them one more time to apply the new DB format....