Re: [BPF v1] tools: bpftool: Fix JSON output when lookup fails

[Quentin Monnet]

2019-06-05 21:17 UTC+0200 ~ Krzesimir Nowak <krzesimir@xxxxxxxxxx>
> In commit 9a5ab8bf1d6d ("tools: bpftool: turn err() and info() macros
> into functions") one case of error reporting was special cased, so it
> could report a lookup error for a specific key when dumping the map
> element. What the code forgot to do is to wrap the key and value keys
> into a JSON object, so an example output of pretty JSON dump of a
> sockhash map (which does not support looking up its values) is:
> 
> [
>     "key": ["0x0a","0x41","0x00","0x02","0x1f","0x78","0x00","0x00"
>     ],
>     "value": {
>         "error": "Operation not supported"
>     },
>     "key": ["0x0a","0x41","0x00","0x02","0x1f","0x78","0x00","0x01"
>     ],
>     "value": {
>         "error": "Operation not supported"
>     }
> ]
> 
> Note the key-value pairs inside the toplevel array. They should be
> wrapped inside a JSON object, otherwise it is an invalid JSON. This
> commit fixes this, so the output now is:
> 
> [{
>         "key": ["0x0a","0x41","0x00","0x02","0x1f","0x78","0x00","0x00"
>         ],
>         "value": {
>             "error": "Operation not supported"
>         }
>     },{
>         "key": ["0x0a","0x41","0x00","0x02","0x1f","0x78","0x00","0x01"
>         ],
>         "value": {
>             "error": "Operation not supported"
>         }
>     }
> ]
> 
> Fixes: 9a5ab8bf1d6d ("tools: bpftool: turn err() and info() macros into functions")
> Cc: Quentin Monnet <quentin.monnet@xxxxxxxxxxxxx>
> Signed-off-by: Krzesimir Nowak <krzesimir@xxxxxxxxxx>

Thanks for the fix!

Quentin