Read json data from Android with php - php

I'm trying to read data from a decompiled application of Android with a php server. I used wireshark to understand what types of data the application sends, and the result is:
{"initType":"first time","parameters":true,"details":................}
I trying to capture this data and insert them in a file with this php code:
<?php
$json = $_POST["initType"];
$decoded = json_decode($json, TRUE);
if ($decoded === FALSE) {
throw new Exception('Bad JSON format.');
}
$file_handle = fopen('tmp.json', 'w');
fwrite($file_handle, $decoded);
fclose($file_handle);
?>
The file is correctly generated but it's empty. What is the error?

Because $decoded is an array, use a loop to write it to file or write the encoded JSON to file ($json). Try using this:
fwrite('tmp.json', print_r($decoded, TRUE));
or:
file_put_contents('tmp.json', print_r($decoded, TRUE));
Update (per your comments):
If you run a print_r($decoded) and it prints nothing, there is a problem with the decoding process of the JSON object passed in. I would recommend checking this to make sure it is formatted correctly. JSON formatting is a strict business and will halt your end goal if you are missing a double-quote or bracket. Start by echoing out $json ($_POST["initType"]) and compare the format to examples posted online (just Google "json formatting"). I can tell you that one thing that stands out to me is: "parameters":true (from your example above). I have a strong suspicion that the key true should be in double quotes. If you are positive that the JSON variable is correct syntactically, I don't think I would be of any more help. Using json_decode() to produce an array to very straight forward once you get it right.

Don't decode the json at all -this only brings the problem of trying to serialize an array that burmat mentioned in his answer.
Write to the file the json content straight away:
fwrite($file_handle, $json);
Also, though I am not PHP expert it seems you access the body of the post request wrongly. Please refer to the following post.

Related

PHP Json Malformed When Posted From jQuery Ajax

I am having a weird issue, when i use json_decode() on some json from a jquery ajax call it's coming back always saying that the json is malformed (JSON_ERROR_SYNTAX).
I say this is weird because if i take a copy of the raw posted json from the developer console and manually push it through json_decode() then it decodes perfectly fine.
I have uploaded a txt file of the example json here : https://drive.google.com/file/d/1IZ5RkpFK7KLUNYeZe4dPdxGWZXinmFSJ/view?usp=sharing which works manually parsing it but not from posted data. Another weird issue is if i save the json string to a longtext field in a mysql database and then pull it out again, it then decodes fine; but this isn't ideal, it needs to validate it before going to the database and i'm unsure why this would allow it to decode anyway.
Any ideas?
This might be happeing due to new line code added in your code. You can add below code and try to decode the code again it might work.
$content = preg_replace('/[\r\n\t\s]+/s', ' ', $content);#new lines, multiple spaces/tabs/newlines
$content = preg_replace('#/\*.*?\*/#', '', $content);#comments
$content = preg_replace('/^\s+/', '', $content);#spaces on the begining

php: json_decode containing HTML fails to decode

I need to use a customer's API for loading JSON which only contains something like:
{"html" : "foo"}
The API is being used from other services so I'm pretty sure it's valid.
However, when trying to decode it using json_decode i'm always getting an empty string which means it's not valid. I found out i need to "fix" the JSON-String by replacing:
$json = str_replace("\\>", "\\\\>", $json); // \> = invalid json
It works mainly on each request but not on certain others but it's very tricky to debug and i can't imagine that replacing is the proper method.
How would i do it the easy way for converting the json string into a valid one?
thanks
Ok i could find out what's wrong:
The HTML contains backslashes in the closing tags, for example <br\>
You need to replace them like this:
$json = str_replace("\\>", "\\\\>", $json);
and json_decode will work

Does echo and print not work in the 'live' version of php?

So I'm quite new to programming, and I have nothing else to describe it but a live script, so please correct me with the official term. Anyway, a while ago, I made this bot in php and ran it locally in my browser using xampp on my mac. I could very easily use echo and print_r to print arrays and whatever to the webpage. The script would only run if I reloaded the page, so this is what i'm talking about as 'not live'. Now I have started trying to make a messenger bot in PHP, and i'm using cloud9. I also see the script in a browser, but here, I can only see products of echo and print if they are simple strings I have entered, for example:
print_r("stack overflow is life");
This will print as expected in my browser. However, this is where me talking about 'live' script runs comes into play. Instead of reloading the page, it runs live. The messenger bot will always be active on the server, and it instantly replies to a message sent to it as wanted. I use this code:
/* receive and send messages */
$input = json_decode(file_get_contents('php://input'), true);
file_put_contents("fb.txt", file_get_contents('php://input'));
echo ("<pre>"); print_r($input);
echo ("</pre>");
Now, in this case, the $input is not printed. I see nothing. Now I don't know if this is to do with live server response, or what, but I need to know how to see this is the browser. And I have tested to see if there actually is a successfully converted JSON to array, because I am able to use the info in $input to reply to my facebook messaged and the bot works. I can also output the JSON to a txt file, and see it there, but there is no <pre> tags so it is hard to read, and I want the nice clean array to see in the browser. All code revolves around this, so it is very important.
So you are writing the raw input to the file and json decoding it separately. So it is quite possible you are not actually getting valid json.
If you do pass invalid json, json_decode returns NULL which is why you see that when you var_dump - so you have to call json_last_error to be sure it worked.
From Docs:
http://php.net/manual/en/function.json-decode.php
Returns the value encoded in json in appropriate PHP type. Values true, false and null are returned as TRUE, FALSE and NULL respectively. NULL is returned if the json cannot be decoded or if the encoded data is deeper than the recursion limit.
You should really check if json_decode works, here is an example to demonstrate:
<?php
$badjson = '{bad:"json"}';
$decoded = json_decode($badjson);
if(json_last_error()!==JSON_ERROR_NONE){
echo "Json Decode Failed: ".json_last_error_msg();
}else{
var_dump($decoded);
}
echo "\n---\n";
$goodjson = '{"property":"value"}';
$decoded = json_decode($goodjson);
if(json_last_error()!==JSON_ERROR_NONE){
echo "Json Decode Failed: ".json_last_error_msg();
}else{
var_dump($decoded);
}
See it in action here: http://sandbox.onlinephpfunctions.com/code/3a07e57f4cd01bd63d2945d5e367bbb0a6158195
See PHP Docs: http://php.net/manual/en/function.json-last-error.php
You can use a syntax checker to find the problem with your json e.g. http://jsonlint.com/
A common issue if the json is manually created is failing to wrap properties in double quotes e.g. {property:"value"} is invalid while {"property":"value"} is valid.
Note the reason you have to check json_last_error, and can't rely on NULL meaning it failed is because json_decode('NULL'); would return NULL and that would be correct.
Not sure what is cloud9.
For debug you can try var_dump() function. It will print onto your browser data type and data values, because there could be different type of "nothing". It's not a better way for debugging but a naive one. For better: check debug and breakpoint possibilities in this cloud9.
var_dump() can eat as many arguments as you like, so it's handy to dump everything with php input too to check what comes and how it changes.

PHP - trouble receiving POST json

I am writing some simple PHP to receive a POST from another system with a JSON payload. That request is Content-Type: application/json.
I'm simply attempting to dump the json into a txt file as a starting point, but that isn't happening. Here's the PHP file, any suggestions/corrections would be much appreciated!
<?php
ini_set("display_errors", "On");
session_start();
$raw_json = file_get_contents('php://input');
$cooked_json = json_decode($raw_json);
$myfile = fopen('/home/wgordon/log.txt','a');
$fp = fwrite($myfile, $cooked_json);
fclose($myfile);
?>
From the look of it, the initial value of $raw_json would be a string. When you try to access it as an array, you're only going to get a smaller string back. When you pass that to json_decode, it's probably going to return null.
You need to inspect that first value of $raw_json. If it is coming in as a query string of name/value pairs, you'll need to decode it (using split() or something similar) before you can treat it like an array

JSON from Javascript not decoding in PHP

I've been going bananas trying to get some data from Javascript on one page to post to a php file asynchronously. I'm not even attempting to do anything with the data, just a var_dump to spit back out from the ajax call. NULL over and over again.
I've checked the JSON with JSONLint and it validates just fine. I'm getting my JSON from JSON.stringify - Firebug tells me I'm getting the following:
{"items":[["sa1074","1060"],["sa1075","1061"]]}
I've tried php://input, as well as json_decode_nice from the PHP manual comments about the function, and I've tried using utf8_encode - is there something wrong with my JSON?
EDIT: Derpity dee probably should have planned this post a bit more haha. Here's my PHP (using a suggestion from PHP manual comments)
function json_decode_nice($json, $assoc = FALSE){
$json = str_replace(array("\n","\r"),"",$json);
$json = preg_replace('/([{,])(\s*)([^"]+?)\s*:/','$1"$3":',$json);
return json_decode($json,$assoc);
}
if (isset($_POST['build'])){
$kit = file_get_contents('php://input');
var_dump(json_decode_nice($kit));
}
And the JS used to create it:
var jsonKit = JSON.stringify(kit);
$.post("kits.php?", {"build" : jsonKit},
function(data) {
$("#kitItems").html(data);
});
Also: Our host is on PHP 5.2 - I found this out when I uploaded a perfectly good redbean class only to have it explode. Had to re-implement with legacy redbean. Our host is busted.
SOLVED: Thanks to all who commented. Didn't think to check $_POST to see what was coming in. Quotes were being escaped with slashes in the $_POST and json_decode was choking on it. Adding this line before decoding solved the problem. Also forgot to set true to return an associative array. Thanks!
$kit = str_replace('\\', '', $kit);
Without seeing code - I'm just guessing here ... are you using a true assoc variable in your json_decode()?
<?php json_decode($jsonString, true); ?>
That had me stumped on a decode for quite some time my first time trying to decode something,

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