parsing json responses in real time in php

Question

I am working on a research project for my graduate program in finance regarding crypto currencies (bitcoin,etc) . I am trying to parse out individual objects from JSON responses produced by cryptsy (market for exchanging crypto currencies) api(https://www.cryptsy.com/pages/privateapi). I am using the API example code given by cryptsy which can be found in the URL provided above. I would like to grab my account balances for starters. your help here would be very much appreciated.

The responses I am getting look like this:

Array
(
    [success] => 1
    [return] => Array
        (
            [balances_available] => Array
                (
                    [42] => 0.00000000
                    [AGS] => 0.00000000
                    [ALN] => 0.00000000
                    [ALF] => 0.00000000
                    [AMC] => 0.00000000

My code I am trying to write not working so well:

$result = api_query("getinfo");
$json = file_get_contents($result);
$json2 = json_decode($json, true);
foreach($json2->attachments->balances_available AS $attach) {
    file_put_contents('test.txt', $attach, FILE_APPEND);


}

echo "<pre>".print_r($json2, true)."</pre>";


Error Message: 

Warning: file_get_contents() expects parameter 1 to be a valid path, array given in /Users/Aditya/Desktop/PHP-1.php on line 45

Warning: Invalid argument supplied for foreach() in /Users/Aditya/Desktop/PHP-1.php on line 47

Any help would be very much appreciated, I have looked all over every forum and I am not a computer science guy. Once again thank you for your time and patience.

Please explain what "not working so well" means. Error message for accessing an array with property names? What gets stored in the file, what did you try to accomplish instead? — mario, Aug 24 '14 at 12:34
Sorry so the error messages say (Parse error: parse error in /Users/Aditya/Desktop/PHP-1.php on line 72) but on line 72 I have commented out (//$result = api_query("calculatefees", array("ordertype" => 'Buy', 'quantity' => 1000, 'price' => '0.005'));) This came directly from the example provided in the example api. I dont know where the file gets stored or even if its being created, and I have not tried to accomplish anything instead..I am stuck..Please forgive me I am very new computer science. — RustyShackleford, Aug 24 '14 at 14:39
So the code in your question is irrelevant then. It's impossible to tell why you got a syntax error there; the error message excerpt is shortened out. And your excerpt does not reveal much. See [PHP Parse/Syntax Errors; and How to solve them?](http://stackoverflow.com/q/18050071) then. You're on your own. — mario, Aug 24 '14 at 14:43
You can always [edit your question](http://stackoverflow.com/posts/25471717/edit) to include relevant information. Don't paste code into comments. That's not readable. Else nobody will notice and have a second look at your questions — mario, Aug 24 '14 at 21:04
Sorry about that Mario. I have corrected the code within the question now. Very new here sorry. Regardless my end goal is that I want to be able to make a call to say [42] and get the balance in my account. — RustyShackleford, Aug 24 '14 at 21:10

score 1 · Accepted Answer · answered Aug 24 '14 at 21:50

The sample api_query method already returns an array:

$array = api_query("getinfo");

Therefore you need to apply neither file_get_contents nor json_decode on the $result variable.

It's a plain array at this point, so just [] accesses, no -> property traversal. I'm not sure it's wrapped in ["attachments"] anyway. See var_dump($array) for the actual structure.

You can just loop over it:

foreach ($array["attachments"]["balances_available"] as $key => $value) {
    print " $key == $value \n<br>";
}

If you want to store it into an file (you may wish to elaborate on the format), then append it likewise:

foreach (/* as seen above*/) {
    file_put_contents(
        'test.txt',
        " $key has $value balance \n",
        FILE_APPEND
    );
}

parsing json responses in real time in php

1 Answers1