Re: bridge mdb json output broken/invalid

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 5 Apr 2019 15:59:03 +0300
Nikolay Aleksandrov <nikolay@cumulusnetworks.com> wrote:

> Hi Stephen,
> It seems that commit c7c1a1ef51aea ("bridge: colorize output and use JSON print library") broke
> bridge mdb's json output. The json after that commit is invalid, more below.
> 
> Setup: 2 bridges - virbr0 and br-test
> 
> non-json bridge mdb show:
> 3: virbr0  vnet3  239.10.10.50  temp 
> 3: virbr0  vnet3  225.1.2.3  temp 
> 14: br-test  v1  224.224.224.224  permanent 
> 
> json bridge -d -p -j mdb show before c7c1a1ef51aea:
> {
>     "mdb": [ {
>             "dev": "virbr0",
>             "port": "vnet3",
>             "grp": "239.10.10.50",
>             "state": "temp"
>         },{
>             "dev": "virbr0",
>             "port": "vnet3",
>             "grp": "225.1.2.3",
>             "state": "temp"
>         },{
>             "dev": "br-test",
>             "port": "v1",
>             "grp": "224.224.224.224",
>             "state": "permanent"
>         } ],
>     "router": {
>         "virbr0": [ {
>                 "port": "vnet3"
>             } ],
>         "br-test": [ {
>                 "port": "v1"
>             } ]
>     }
> }
> 
> json bridge -d -p -j mdb show after c7c1a1ef51aea:
> [ 
>     "mdb": [ {
>             "index": 3,
>             "dev": "virbr0",
>             "port": "vnet3",
>             "grp": "239.10.10.50",
>             "state": "temp",
>             "flags": [ ]
>         },{
>             "index": 3,
>             "dev": "virbr0",
>             "port": "vnet3",
>             "grp": "225.1.2.3",
>             "state": "temp",
>             "flags": [ ]
>         } ],
>     "router": [ 
>         "virbr0": [ {
>                 "port": "vnet3"
>             } ] ],
>     "mdb": [ ],
>     "mdb": [ {
>             "index": 14,
>             "dev": "br-test",
>             "port": "v1",
>             "grp": "224.224.224.224",
>             "state": "permanent",
>             "flags": [ ]
>         } ],
>     "router": [ 
>         "br-test": [ {
>                 "port": "v1"
>             } ] ] ]
> 
> 
> Obviously this is not a valid object array and even if it was converted, it must not contain
> duplicate entries. The "mdb" and "router" array entries must be unique and should contain
> all the single entries inside, also the global context shouldn't be array.
> 
> Cheers,
>  Nik

Yes this is wrong, sending the list twice.
Not sure why that is happening, the original code had some awkward flags to handle this.