Accessing a child node using JSON within PHP and file_get_contents() - php

Question

OK I am stumped.
I have tried numerous different approaches and I've spent the best part of a good few hours searching to no avail to my exact situation, that or I am tired and blind.
Here is the raw json pulled from a URI using file_get_contents():
{"id":"XXX","name":"Customer1","os":"CentOS Linux 7.3.1611 Core","cpu_type":"Intel(R) Xeon(R) CPU E3-1245 V2 # 3.40GHz","networking_v4":[{"addr":"xxx.xxx.xxx.xxx","if":"eth0"}],"networking_v6":[{"addr":"xxxx","if":"eth0"},{"addr":"xxxx","if":"eth0"}],"agent_version":0.96,"status":"up","last_update":1505949230,"first_update":1500588943,"notifications_count":8,"ip_whois":{"ip":"xxx.xxx.xxx.xxx","hostname":"xxx","city":"Garwood","region":"New Jersey","country":"US","loc":"xxx","org":"AS20473 Choopa, LLC","postal":"xxx"},"additional_fields":[{"value":"xxx","key":"Datacenter"},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""},{"value":"","key":""}]}
As you can see its a pretty simple request and I have every bit of data except those nested within networking_v4 and networking_v6.
I tried to access those like so:
'ipv4' => $json->networking_v4->addr,
'ipv4dev' => $json->networking_v4->if,
'ipv6' => $json->networking_v6->addr,
'ipv6dev' => $json->networking_v6->if,
Here is the full snapshot of code in its entirety:
$content = file_get_contents($url);
$json = json_decode($content);
$server_lastupd = $json->last_update;
$server_firstupd = $json->first_update;
$server = array(
'id' => $json->id,
'name' => $json->name,
'os' => $json->os,
'cputype' => $json->cpu_type,
'ipv4' => $json->networking_v4->addr,
'ipv4dev' => $json->networking_v4->if,
'ipv6' => $json->networking_v6->addr,
'ipv6dev' => $json->networking_v6->if,
'status' => $json->status,
'lastupd' => $json->$server_lastupd,
'firstupd' => $json->$server_firstupd,
'notifications' => $json->notifications_count,
'ip' => $json->ip_whois->ip,
'hostname' => $json->ip_whois->hostname,
'city' => $json->ip_whois->city,
'region' => $json->ip_whois->region,
'country' => $json->ip_whois->country,
'loc' => $json->ip_whois->loc,
'org' => $json->ip_whois->org,
'postal' => $json->ip_whois->postal,
'dctag' => $json->additonal_fields->dctag,
'source' => "XXX"
);
return $server;
So my issue is I appear to be unable to access the child content within networking_v4 and networking_v6.
Any help on this would be massively appreciated, its stumped me for the best part of 6 hours last night and a few more today, so I give in, someone please show me the light!
Many thanks :)

Answer 1

It looks like those are nested in arrays from the [{"key':"value"},{"key":"value"}] square brackets. have you tried
ipv4 => $json->networking_v4[0]->addr,

Answer 2

Try $json->networking_v4[0]->addr.
Both the networking_v4 and the networking_v6 keys point to arrays, so you need to pick which index you want to look at. The former only has one element, so it's easy to pick index 0, but the latter has multiple elements, so you'll need to figure out which one you want.