Question

In Fedora 17 64bit while using netifaces and json imports.

I’m trying to get this format in JSON

"net_info" : [
            {"nic" : ..., "mac" : ..., "ip" : ...},
            {"nic" : ..., "mac" : ..., "ip" : ...},
            {"nic" : ..., "mac" : ..., "ip" : ...},
            ]

I’m currently using a string and just appending to it, and I get this:

"'net_info': [{'nic':eth0,'mac':6c:f0:49:0f:e1:c2,'ip':192.168.1.116},]"

This may not work due to the quotes at the beginning and the end of each string; is there a better way of accomplishing this? I was thinking of using a List of Dictionaries but ended up trying strings first, not sure what would best in this case.

Here’s my code that takes in 3 lists:

def json_serialize(ip=[],mac=[],nic=[]):
    jsonDump = "'net_info': ["
    for i,item in enumerate(ip):
        jsonDump += "{'interface_name':" + nic[i] +",'mac':" 
                      + mac[i] + ",'ip':" + ip[i] +"},"
        jsonDump += "]"
        print jsonDump.strip()

    #Testing output after its passed in to json.dumps(), it now has quotes at beginning
    #and end of string...?
    print "\n"
    print     json.dumps(jsonDump)

Answer 1

Just create a python dict with a contained list instead, then dump that to JSON in one go:

def json_serialize(ip, mac, nic):
    net_info = []
    for ipaddr, macaddr, nicname in zip(ip, mac, nic):
        net_info.append({
            'interface_name': nicaddr,
            'mac': macaddr,
            'ip': ipaddr
        })
    return json.dumps({'net_info': net_info})

Your desired output format seems to be missing the outer { and } brackets to mark it a proper JSON object. If you really have to produce that output (so missing those brackets), just remove them again:

print json_serialize(ip, mac, nic)[1:-1]