In early days of YNL development dumping the NlMsg on errors was quite useful, as the library itself could have been buggy. These days increasingly the NlMsg is just taking up screen space and means nothing to a typical user. Try to format the errors more in line with how YNL C formats its errors strings. Before: $ ynl --family ethtool --do channels-set --json '{}' Netlink error: Invalid argument nl_len = 44 (28) nl_flags = 0x300 nl_type = 2 error: -22 extack: {'miss-type': 'header'} $ ynl --family ethtool --do channels-set --json '{..., "tx-count": 999}' Netlink error: Invalid argument nl_len = 88 (72) nl_flags = 0x300 nl_type = 2 error: -22 extack: {'msg': 'requested channel count exceeds maximum', 'bad-attr': '.tx-count'} After: $ ynl --family ethtool --do channels-set --json '{}' Netlink error: Invalid argument {'miss-type': 'header'} $ ynl --family ethtool --do channels-set --json '{..., "tx-count": 999}' Netlink error: requested channel count exceeds maximum: Invalid argument {'bad-attr': '.tx-count'} Signed-off-by: Jakub Kicinski --- CC: donald.hunter@gmail.com CC: ast@fiberby.net --- tools/net/ynl/pyynl/lib/ynl.py | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/tools/net/ynl/pyynl/lib/ynl.py b/tools/net/ynl/pyynl/lib/ynl.py index 62383c70ebb9..bac9eb33ba89 100644 --- a/tools/net/ynl/pyynl/lib/ynl.py +++ b/tools/net/ynl/pyynl/lib/ynl.py @@ -105,7 +105,17 @@ from .nlspec import SpecFamily self.error = -nl_msg.error def __str__(self): - return f"Netlink error: {os.strerror(self.error)}\n{self.nl_msg}" + msg = "Netlink error: " + + extack = self.nl_msg.extack.copy() if self.nl_msg.extack else {} + if extack: + if 'msg' in extack: + msg += extack['msg'] + ': ' + del extack['msg'] + msg += os.strerror(self.error) + if extack: + msg += ' ' + str(extack) + return msg class ConfigError(Exception): -- 2.51.0