sudo /script.py - 在 .php 中读出温度和湿度

Question

我目前正在使用我的 Raspberry Pi B+ 进行一个项目。
我正在使用 DHT22 - 温度和湿度传感器。我也在使用与 python 一起工作的 Adafruit。

我的问题是，我真的不知道如何在我的 .php 脚本中读出我想在 index.php（Apache-Server）中实现的特定内容。

我可以通过以下方式读取腻子上的温度和湿度：

sudo /root/Adafruit_Python_DHT/examples/AdafruitDHT.py 22 4

而 22 是 DHT “22” 传感器 - 因为有一个较旧的传感器名为“11”，而 4 是覆盆子的 GPIO。

putty 现在告诉我们：

root@raspberrypi:~# sudo /root/Adafruit_Python_DHT/examples/AdafruitDHT.py 22 4
Temp=21.3*  Humidity=41.6%

AdafruitDHT.py 本身如下所示：

#!/usr/bin/python
# Copyright (c) 2014 Adafruit Industries
# Author: Tony DiCola

# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
import sys

import Adafruit_DHT


# Parse command line parameters.
sensor_args = { '11': Adafruit_DHT.DHT11,
                '22': Adafruit_DHT.DHT22,
                '2302': Adafruit_DHT.AM2302 }
if len(sys.argv) == 3 and sys.argv[1] in sensor_args:
    sensor = sensor_args[sys.argv[1]]
    pin = sys.argv[2]
else:
    print('usage: sudo ./Adafruit_DHT.py [11|22|2302] GPIOpin#')
    print('example: sudo ./Adafruit_DHT.py 2302 4 - Read from an AM2302 connected to GPIO #4')
    sys.exit(1)

# Try to grab a sensor reading.  Use the read_retry method which will retry up
# to 15 times to get a sensor reading (waiting 2 seconds between each retry).
humidity, temperature = Adafruit_DHT.read_retry(sensor, pin)

# Un-comment the line below to convert the temperature to Fahrenheit.
# temperature = temperature * 9/5.0 + 32

# Note that sometimes you won't get a reading and
# the results will be null (because Linux can't
# guarantee the timing of calls to read the sensor).
# If this happens try again!
if humidity is not None and temperature is not None:
    print('Temp={0:0.1f}*  Humidity={1:0.1f}%'.format(temperature, humidity))
else:
    print('Failed to get reading. Try again!')
    sys.exit(1)

我的 .php 看起来像这样：

<?php

$temp = exec('cat /root/Adafruit_Python_DHT/examples/AdafruitDHT.py |grep Temp=');
$temp = explode('Temp=',$temp);
$temp = round($temp,2);

echo $temp;
?>

我知道我的第一行是不正确的。
但我不知道如何读出实时温度和实时湿度。而且我不知道究竟该用谷歌搜索什么。

编辑 1：

使用以下 .php 文件，网站看起来像这样：

`

如您所见，它仅缺少来自 DHT22 传感器的输出。

Answer 1

如果你这样做了

cat /root/Adafruit_Python_DHT/examples/AdafruitDHT.py | grep Temp=

您没有运行/执行 AdafruitDHT.py 程序，您正在复制它的内容（即 python 程序文本）所以您将从 PHP exec 得到的可能是匹配行

print('Temp={0:0.1f}* Humidity={1:0.1f}%'.format(温度, 湿度))

将该行更改为：

$temp = exec('python /root/Adafruit_Python_DHT/examples/AdafruitDHT.py | grep Temp=') 

在确保允许在 PHP exec 调用中使用管道 (|) 之后。 （如果不考虑将脚本的输出仅剥离为您希望在 PHP 中拥有的内容，则删除 | grep .... 部分）。