accessing $_POST array variables in php - php

Question

I'm able to access my $_POST array values, but can't seem to get the correct syntax for returning only the "data" part of the array. If I run var_dump($_POST["attributes"]);, I receive the following in the response callback(which is exactly what I expected):
string '{
"device_maker" = unknown;
"device_model" = Simulator;
"first_visit" = "1387478168.109";
"last_visit" = "1388358490.638";
latitude = "37.78583526611328";
locale = en;
longitude = "-122.4064178466797";
"opted_in" = 1;
"opted_out" = 0;
"os_platform" = "iPhone OS";
"os_version" = "7.0.3";
"this_visit" = "1387478168.109";
"user_id" = 1;
}' (length=389)
If I try to access any one of the attributes separately, like var_dump($_POST["attributes"]["device_model"]);, all I get in return is string '{' (length=1). I'm apparently missing a key idea on parsing this data. How do I parse "attributes" so I can place each one of the listed values into an insert statement(I've got that part ready to go once I get the data)? Granted, my php is very rusty. So I may be overlooking something obvious.
It's frustrating to see the data I need and not know how to correctly access it. So, any help is appreciated. Please ask if you need clarification.

Answer 1

Apparently the string being retrieved in your POST is not valid JSON. If you can't replace the values being sent to the server, you can always do a (dirty) workaround:
First, replace some characters to make it a valid json:
$jsonStr = str_replace('=', ':', $_POST["attributes"]);
$jsonStr = str_replace(';', ',', $jsonStr);
$jsonStr = str_replace(',}', '}', $jsonStr);
Then we can try to parse it using the json_decode function:
$jsonArray = json_decode($jsonStr);
Now you can access it as a regular associative array, e.g.:
echo $jsonArray['device_model'];

Answer 2

What you show here looks like JSON encoded data - it's a single string so there is no $_POST["attributes"]["device_model"].
You can access the data embedded in the attributes variable by converting it from JSON:
$a_string='{
"device_maker" = unknown;
"device_model" = Simulator;
"first_visit" = "1387478168.109";
"last_visit" = "1388358490.638";
latitude = "37.78583526611328";
locale = en;
longitude = "-122.4064178466797";
"opted_in" = 1;
"opted_out" = 0;
"os_platform" = "iPhone OS";
"os_version" = "7.0.3";
"this_visit" = "1387478168.109";
"user_id" = 1;
}';
// or $astring=$_POST['attributes']
$data=json_decode($a_string);
print $data['device_model'];
....but you need to verify the origin of the data - if it' not JSON, then this will break at some point.