Python请求库发布请求在本地开发服务器上失败？

Question

Ok so I have been looking at the code I have for far too long I know through I number of tests that I must be facing an issue beyond the scope of my knowledge.

In short, I am trying to send data that I have received from an Arduino (connected to my laptop, and communicating via serial port) to a server that is running on my laptop.

I am trying to send various pieces of information in a POST requests using the Requests Library as follows:

import requests
import json

url = 'http://<usernames computer>.local/final/'
headers = {'Content-type': 'application/json'}
data = [
    ('state','true'),
    ('humidity', 45),
    ('temperature',76)
]

r = requests.post(url, data, headers = headers)

print r.text

This code works. I know this because I tested it at http://www.posttestserver.com/ . All of the data is sent properly.

But I am trying to send it to a server side script that looks like this:

<?php   
$state = $_POST["state"];

$myfile = fopen("./data/current.json", "w") or die("Unable to open file!");
$txt = "$state";

fwrite($myfile, $txt);
fclose($myfile);

echo "\nThe current state is:\n $state\n";

?>

However when I run the code, my script spits out:

<br />
<b>Notice</b>:  Undefined index: state in
<b>/Applications/XAMPP/xamppfiles/htdocs/final/index.php</b> on line   
<b>2</b><br />

The current state is:
<This is where something should come back, but does not.>

What could be going wrong? Thanks for your help!

Answer 1

$state = $_POST["state"];

You are sending the data as type application/json , but PHP won't auto de-serialize the string into json for you. Also Python Requests will not autoserialize:

[
('state','true'),
('humidity', 45),
('temperature',76)
]

into json.

What you will want to do is serialize the request for on the client side:

data = [
    ('state','true'),
    ('humidity', 45),
    ('temperature',76)
]

r = requests.post(url, json=data, headers=headers)

Now on the server side, de-serialize it:

if ($_SERVER["CONTENT_TYPE"] == "application/json") {
    $postBody = file_get_contents('php://input');
    $data = json_decode($postBody);

    $state = $data["state"];
    //rest of your code...
}