用树莓派学编程系列1——树莓派状态读取

树莓派运行状态：CPU温度，使用率，内存，硬盘，电压等值

树莓派系列1——树莓派状态读取

前期准备

• 环境要求python

  安装方式见
  http://blog.csdn.net/weixiazailaide/article/details/52735076

• 安装rpi.gpio
  由于pip安装时总出现超时错误，建议用国内镜像或者超时提高到6000

sudo pip install pip.gpio -timeout 6000

读取树莓派的状态

创建raspberrypistate应用

创建

cd  /home/pi/helloworldpython manage.py startapp raspberrypistate

配置django

• 配置settings.py

cd helloworldvim settings.py

settings.py 需要在INSTALLED_APPS 处添加
'raspberrypistate.apps.raspberrypistateConfig',
把TEMPLATES 中DIRS更改为
'DIRS': [os.path.join(BASE_DIR, 'templates')],
如下所示

# Application definitionINSTALLED_APPS = [    'raspberrypistate.apps.RaspberrypistateConfig',    'django.contrib.admin',    'django.contrib.auth',    'django.contrib.contenttypes',    'django.contrib.sessions',    'django.contrib.messages',    'django.contrib.staticfiles',]TEMPLATES = [    {        'BACKEND': 'django.template.backends.django.DjangoTemplates',        'DIRS': [os.path.join(BASE_DIR, 'templates')],        'APP_DIRS': True,        'OPTIONS': {            'context_processors': [                'django.template.context_processors.debug',                'django.template.context_processors.request',                'django.contrib.auth.context_processors.auth',                'django.contrib.messages.context_processors.messages',            ],        },    },]

• 配置urls.py

vim urls.py

urls.py更改为以下内容即可

from django.conf.urls import include, urlfrom django.contrib import adminurlpatterns = [    url(r'^raspberrypistate/', include('raspberrypistate.urls',namespace="raspberrypistate")),    url(r'^admin/', admin.site.urls),]

• Django接收raspberrypistate的更改

cd ..python manage.py migratepython manage.py makemigrations raspberrypistate

• 配置raspberrypistate的urls.py

cd raspberrypistatevim urls.py

urls.py

from django.conf.urls import urlfrom . import viewsurlpatterns = [    url(r'^$', views.index, name='index'),]

• 写views.py

vim views.py

views.py

# -*- coding:utf-8 -*-from django.http import HttpResponse# Create your views here.def index(request):    return HttpResponse("Hello, world. 树莓派状态显示")

初步配置完成，进行测试

测试django配置

• 重启uwsgi服务

sudo systemctl restart emperor.uwsgi.service

在树莓派浏览器输入
http://127.0.0.1/raspberrypistate
或者在电脑浏览器输入 http://raspberrypi/raspberrypistate

测试完成

读取树莓派CPU温度

• 创建状态读取文件state.py

vim state.py

state.py

# -*- coding:utf-8 -*-import commandsdef getCPUtemperature():    res = commands.getoutput('vcgencmd measure_temp').replace( 'temp=', ''    ).replace( '\'C', '' )    tem = "CPU温度: "+str(res)+"°C"    return tem

• 更改views.py

 vim views.py 

views.py

# -*- coding:utf-8 -*-from django.http import HttpResponsefrom . import state# Create your views here.def index(request):        tem=state.getCPUtemperature()        return HttpResponse(tem)

• 重启uwsgi服务

sudo systemctl restart emperor.uwsgi.service

在树莓派浏览器输入
http://127.0.0.1/raspberrypistate
或者在电脑浏览器输入 http://raspberrypi/raspberrypistate

测试完成

读取树莓派状态

• 修改state.py文件

vim state.py

state.py

## -*- coding:utf-8 -*-import commandsdef getCPUtemperature():    return float(commands.getoutput('vcgencmd measure_temp')\                      .replace('temp=','').replace('\'C', ''))def getRAMinfo():    return commands.getoutput('free').split()[7:10]def getCPUuse():    return commands.getoutput("top -bcn 1").split()[24]def getDiskSpace():    return commands.getoutput("df -h /").split()[7:11]def getPiVolts():        volts=["core","sdram_c","sdram_i","sdram_p"]        res={}        for volt in volts:                res[volt]=float(commands\                                .getoutput("vcgencmd measure_volts "+volt)\                                .replace('volt=','')\                                .replace('V',''))    return resdef getCPU():    tem = "CPU温度: "+str(getCPUtemperature())+"°C "    RAM_info=getRAMinfo()        inf = "RAM_total: "+str(round(int(RAM_info[0])/1000,1))+"MB  \               RAM_used: "+str(round(int(RAM_info[1])/1000,1))+"MB  \               RAM_free: "+str(round(int(RAM_info[2])/1000,1))+"MB  "    use = "CPU使用率: "+str(getCPUuse())+"%  "    disk_space=getDiskSpace()    space = "硬盘容量: "+disk_space[0]+"B\                 已用: "+disk_space[1]+"B  \                 可用: "+disk_space[2]+"B  \                 使用率: "+disk_space[3]+"  "    pi_volts=getPiVolts();    volts=""    for volt,value in pi_volts.items():                volts+=(volt+"电压: "+str(round(value,2))+"V  ")    CPUstate=tem+inf+use+space+volts    return CPUstate

• 修改views.py文件

vim views.py

views.py

# -*- coding:utf-8 -*-from django.http import HttpResponsefrom . import state# Create your views here.def index(request):        tem=state.getCPU()        return HttpResponse(tem)

• 重启uwsgi服务

sudo systemctl restart emperor.uwsgi.service

在树莓派浏览器输入
http://127.0.0.1/raspberrypistate
或者在电脑浏览器输入 http://raspberrypi/raspberrypistate

测试完成

历时曲线制作学习中

待续。。。

参考教程

django官方文档
https://docs.djangoproject.com/en/1.10/intro/tutorial01/