在python脚本中循环，阻止网页重新加载

Question

下午所有，

我有一个用于编写NFC标签的网页。当我在页面上提交表单时，PHP将变量发送到python脚本。此脚本（write.py）检查read.py脚本是否已终止并处理写入请求。这部分工作正常。

我遇到的问题是当我回想起read.py时，它包含一个循环，它会阻止网页在写完成后刷新。我试过从PHP脚本内部和write.py结束时调用read.py，同样的事情发生了。我也试过添加一个＆amp;到read.py命令的末尾。

有人可以看一下我到目前为止的情况，让我知道我做错了什么以及如何解决这个问题。

干杯，

的Blinky

HTML / PHP

<?php
session_start();
if( !empty( $_POST ) )
{
    echo "Write to card using python";
    $company = $_POST[ 'company' ];
    $name    = $_POST[ 'name' ];
    $email   = $_POST[ 'email' ];
    $cmd     = "sudo python write.py '$company' '$name' '$email' &";
    $resp    = shell_exec( $cmd );
    if( strpos( $resp, 'written' ) !== false )
    {
        header("Location: http://192.168.1.176/index.php");
    }
    unset( $_POST );
}
?>

<form action="<?php echo $_SERVER["PHP_SELF"]; ?>" method="post">
    <input type="text" name="name" id="name">
    <input type="text" name="email" id="email">
    <select name="company" id="company">
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
        <option value="4">4</option>
    </select>
    <input type="submit">
</form>

read.py

#!/usr/bin/env python
# -*- coding: utf8 -*-

import RPi.GPIO as GPIO
import MFRC522
import signal
import MySQLdb
import os
from datetime import datetime

os.system("sudo kill $(ps aux | grep 'write.py' | awk '{print $2}')")

db = MySQLdb.connect(host="", user="", passwd="", db="")
cursor = db.cursor()

continue_reading = True

# Capture SIGINT for cleanup when the script is aborted
def end_read(signal,frame):
    global continue_reading
    print "Ctrl+C captured, ending read."
    continue_reading = False
    GPIO.cleanup()

# Hook the SIGINT
signal.signal(signal.SIGINT, end_read)

# Create an object of the class MFRC522
MIFAREReader = MFRC522.MFRC522()

# Welcome message
print "Welcome to the MFRC522 data read example"
print "Press Ctrl-C to stop."

# This loop keeps checking for chips. If one is near it will get the UID and authenticate
while continue_reading:

    # Scan for cards    
    (status,TagType) = MIFAREReader.MFRC522_Request(MIFAREReader.PICC_REQIDL)

    # If a card is found
    if status == MIFAREReader.MI_OK:
    print "Card detected"

    # Get the UID of the card
    (status,uid) = MIFAREReader.MFRC522_Anticoll()

    # If we have the UID, continue
    if status == MIFAREReader.MI_OK:

        uid_str = str(uid[0])+"."+str(uid[1])+"."+str(uid[2])+"."+str(uid[3])
        # Print UID
        #print "Card read UID: "+str(uid[0])+","+str(uid[1])+","+str(uid[2])+","+str(uid[3])
        #print "\n".join(str(uid))    
        # This is the default key for authentication
        key = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]

        # Select the scanned tag
        MIFAREReader.MFRC522_SelectTag(uid)

        # Authenticate
        status = MIFAREReader.MFRC522_Auth(MIFAREReader.PICC_AUTHENT1A, 8, key, uid)

        # Check if authenticated
        if status == MIFAREReader.MI_OK:
            print "Inserting data"
            data = MIFAREReader.MFRC522_Read(8)
            try:
                date_time = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
                query = "INSERT INTO %s (tag_uid, company, date_time, card_data) VALUES ('%s', '%s', '%s', '%s')"%('attendance_reader',uid_str,1,str(date_time),data)
                cursor.execute(query)
                db.commit()
                print "Data committed"
            except (MySQLdb.Error, MySQLdb.Warning) as e:
                print(e)
                print "Error: the database is being rolled back"
                db.rollback()
            MIFAREReader.MFRC522_StopCrypto1()
        else:
            print "Authentication error"

write.py

#!/usr/bin/env python
# -*- coding: utf8 -*-

import RPi.GPIO as GPIO
import MFRC522
import signal
import sys
import binascii
import os
import time
from random import randint

os.system("sudo kill $(ps aux | grep 'read.py' | awk '{print $2}')")

company = sys.argv[1]
name    = sys.argv[2]
email   = sys.argv[3]

ident_code = [int(company)]
for x in range(0,15):
    ident_code.append(randint(001, 255))

print ident_code

continue_reading = True

# Capture SIGINT for cleanup when the script is aborted
def end_read(signal,frame):
    global continue_reading
    print "Ctrl+C captured, ending read."
    continue_reading = False
    GPIO.cleanup()

# Hook the SIGINT
signal.signal(signal.SIGINT, end_read)

# Create an object of the class MFRC522
MIFAREReader = MFRC522.MFRC522()

# This loop keeps checking for chips. If one is near it will get the UID and authenticate
while continue_reading:

    # Scan for cards    
    (status,TagType) = MIFAREReader.MFRC522_Request(MIFAREReader.PICC_REQIDL)

    # If a card is found
    if status == MIFAREReader.MI_OK:
        print "Card detected"

    # Get the UID of the card
    (status,uid) = MIFAREReader.MFRC522_Anticoll()

    # If we have the UID, continue
    if status == MIFAREReader.MI_OK:

    # This is the default key for authentication
    key = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]

    # Select the scanned tag
    MIFAREReader.MFRC522_SelectTag(uid)

    # Authenticate
    status = MIFAREReader.MFRC522_Auth(MIFAREReader.PICC_AUTHENT1A, 8, key, uid)
    #print "\n"

    # Check if authenticated
    if status == MIFAREReader.MI_OK:

        #print "Sector 8 will now be filled with 0xFF:"
        # Write the data
        MIFAREReader.MFRC522_Write(8, ident_code)

        # Stop
        MIFAREReader.MFRC522_StopCrypto1()
        #time.sleep(5)
        continue_reading = False
        os.system( "sudo python read.py" )
        # os.system( "sudo python read.py &" )
        # os.system( "sudo kill $(ps aux | grep 'write.py' | awk '{print $2}')" )
        # Make sure to stop reading for cards
    else:
        print "Authentication error"