[PATCH net-next v3 2/6] tools/net/ynl: Report netlink errors without stacktrace

[Donald Hunter <donald.hunter@gmail.com>]

ynl does not handle NlError exceptions so they get reported like program
failures. Handle the NlError exceptions and report the netlink errors
more cleanly.

Example now:

Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
	error: -2	extack: {'bad-attr': '.op'}

Example before:

Traceback (most recent call last):
  File "/home/donaldh/net-next/./tools/net/ynl/cli.py", line 81, in <module>
    main()
  File "/home/donaldh/net-next/./tools/net/ynl/cli.py", line 69, in main
    reply = ynl.dump(args.dump, attrs)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/donaldh/net-next/tools/net/ynl/lib/ynl.py", line 906, in dump
    return self._op(method, vals, [], dump=True)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/donaldh/net-next/tools/net/ynl/lib/ynl.py", line 872, in _op
    raise NlError(nl_msg)
lib.ynl.NlError: Netlink error: No such file or directory
nl_len = 44 (28) nl_flags = 0x300 nl_type = 2
	error: -2	extack: {'bad-attr': '.op'}

Signed-off-by: Donald Hunter <donald.hunter@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
---
 tools/net/ynl/cli.py          | 18 +++++++++++-------
 tools/net/ynl/lib/__init__.py |  4 ++--
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/tools/net/ynl/cli.py b/tools/net/ynl/cli.py
index e8a65fbc3698..f131e33ac3ee 100755
--- a/tools/net/ynl/cli.py
+++ b/tools/net/ynl/cli.py
@@ -6,7 +6,7 @@ import json
 import pprint
 import time
 
-from lib import YnlFamily, Netlink
+from lib import YnlFamily, Netlink, NlError
 
 
 class YnlEncoder(json.JSONEncoder):
@@ -66,12 +66,16 @@ def main():
     if args.sleep:
         time.sleep(args.sleep)
 
-    if args.do:
-        reply = ynl.do(args.do, attrs, args.flags)
-        output(reply)
-    if args.dump:
-        reply = ynl.dump(args.dump, attrs)
-        output(reply)
+    try:
+        if args.do:
+            reply = ynl.do(args.do, attrs, args.flags)
+            output(reply)
+        if args.dump:
+            reply = ynl.dump(args.dump, attrs)
+            output(reply)
+    except NlError as e:
+        print(e)
+        exit(1)
 
     if args.ntf:
         ynl.check_ntf()
diff --git a/tools/net/ynl/lib/__init__.py b/tools/net/ynl/lib/__init__.py
index f7eaa07783e7..9137b83e580a 100644
--- a/tools/net/ynl/lib/__init__.py
+++ b/tools/net/ynl/lib/__init__.py
@@ -2,7 +2,7 @@
 
 from .nlspec import SpecAttr, SpecAttrSet, SpecEnumEntry, SpecEnumSet, \
     SpecFamily, SpecOperation
-from .ynl import YnlFamily, Netlink
+from .ynl import YnlFamily, Netlink, NlError
 
 __all__ = ["SpecAttr", "SpecAttrSet", "SpecEnumEntry", "SpecEnumSet",
-           "SpecFamily", "SpecOperation", "YnlFamily", "Netlink"]
+           "SpecFamily", "SpecOperation", "YnlFamily", "Netlink", "NlError"]
-- 
2.42.0