树莓派学习笔记——webiopi配置文件说明

0.前言

    webiopi是一个可控制树莓派GPIO的web框架，该框架面向物联网IoT开发。该项目托管于google，并可在sourceforge上下载到源代码。现在webiopi已经发展到0.7版本，webiopi支持REST Server，CoAP server，并提供python库和javascript库，毫无疑问的说webiopi是一个优秀的框架。从sourceforge上的信息来看，下载量前三位为美国，德国和英国，天朝的下载量排在了26位（2014年3月8日），所以我觉得应该写点什么普及一下webiopi，并顺便激励一下仍在玩“单片机”的中国嵌入式工程师们，往前走“一步”海阔天空也。

    要熟练使用webiopi，先要对webiopi的配置有所了解，webiopi通过某一个config文件实现。

 

1.GPIO初始化

[GPIO]

# Initialize following GPIOs with given function and optional value

# This is used during WebIOPi start process

#21 = IN

#23 = OUT 0

#24 = OUT 0

#25 = OUT 1

 

【作用】

webiopi运行之后立即设置GPIO端口的状态，例如输入还是输出，若是输出的话输出高电平还是低电平

 

2.GPIO重置

[~GPIO]

# Reset following GPIOs with given function and optional value

# This is used at the end of WebIOPi stop process

#21 = IN

#23 = IN

#24 = IN

#25 = OUT 0

 

【作用】

webiopi结束运行之前，设置GPIO状态。该设置最好和GPIO初始化相对应，更确切的说恢复所有的GPIO为输入。

 

3.载入脚本

[SCRIPTS]

# Load custom scripts syntax :

# name = sourcefile

# each sourcefile may have setup, loop and destroy functions and macros

#myscript = /home/pi/webiopi/examples/scripts/macros/script.py

 

【作用】

script.py可理解为一个主文件，主文件中包含3大块内容，setup loop和destroy。webiopi运行之后的顺序依次是：setup运行一次，webiopi运行时loop连续运行，webiopi运行结束之前destroy运行一次。script.py文件的主要功能存在于loop中，在没有网页操作时，loop中的相关操作也会运行。

 

4.HTTP服务

# HTTP Server configuration

enabled = true

port = 8000

 

# File containing sha256(base64("user:password"))

# Use webiopi-passwd command to generate it

passwd-file = /etc/webiopi/passwd

 

# Change login prompt message

prompt = "WebIOPi"

 

# Use doc-root to change default HTML and resource files location

#doc-root = /home/pi/webiopi/examples/scripts/macros

 

# Use welcome-file to change the default "Welcome" file

#welcome-file = index.html

 

【作用】

1.使能或者禁止HTTP服务

2.设置HTTP服务的端口号，默认为8000，注意由于存在web各种web服务器（apache或者lighttpd），所有请勿使用80端口。

3.设置登录用户名和密码，若是新手建议不用修改。

4.设置html文件目录（请注意是目录而不是文件）。该设置经常会被修改。

 

5.CoAP服务

# CoAP Server configuration

enabled = true

port = 5683

# Enable CoAP multicast

multicast = true

 

【作用】

1.使能CoAP服务

2.CoAP的默认端口为5683，不建议修改。

 

6.载入设备

[DEVICES]

# Device configuration syntax:

# name = device [args...]

# name : used in the URL mapping

# device : device name

# args : (optional) see device driver doc

# If enabled, devices configured here are mapped on REST API /device/name

# Devices are also accessible in custom scripts using deviceInstance(name)

# See device driver doc for methods and URI scheme available

 

# Raspberry native UART on GPIO, uncomment to enable

# Don't forget to remove console on ttyAMA0 in /boot/cmdline.txt

# And also disable getty on ttyAMA0 in /etc/inittab

#serial0 = Serial device:ttyAMA0 baudrate:9600

 

# USB serial adapters

#usb0 = Serial device:ttyUSB0 baudrate:9600

#usb1 = Serial device:ttyACM0 baudrate:9600

 

#temp0 = TMP102

#temp1 = TMP102 slave:0x49

#temp2 = DS18B20

#temp3 = DS18B20 slave:28-0000049bc218

 

#bmp = BMP085

 

#gpio0 = PCF8574

#gpio1 = PCF8574 slave:0x21

 

#light0 = TSL2561T

#light1 = TSL2561T slave:0b0101001

 

#gpio0 = MCP23017

#gpio1 = MCP23017 slave:0x21

#gpio2 = MCP23017 slave:0x22

 

#pwm0 = PCA9685

#pwm1 = PCA9685 slave:0x41

 

#adc0 = MCP3008

#adc1 = MCP3008 chip:1 vref:5

#dac1 = MCP4922 chip:1

 

【作用】

载入各种设备，由于设备暂缺未详细测试。

 

7.REST设置

# By default, REST API allows to GET/POST on all GPIOs

# Use gpio-export to limit GPIO available through REST API  

#gpio-export = 21, 23, 24, 25

 

# Uncomment to forbid changing GPIO values 

#gpio-post-value = false

 

# Uncomment to forbid changing GPIO functions 

#gpio-post-function = false 

 

# Uncomment to disable automatic device mapping

#device-mapping = false

【作用】

默认的情况下，通过REST API可以控制所有的GPIO端口。这些危险操作会和loop中的功能冲突，为了防止该情况可通过配置限制REST的功能，例如设置GPIO的方法和输出电平。

 

8.URL重路由

# Custom REST API route syntax :

# source = destination

# source : URL to route

# destination : Resulting URL

# Adding routes allows to simplify access with Human comprehensive URLs

 

# In the next example with have the bedroom light connected to GPIO 25

# and a temperature sensor named temp2, defined in [DEVICES] section

# - GET /bedroom/light => GET /GPIO/25/value, returns the light state

# - POST /bedroom/light/0 => POST /GPIO/25/value/0, turn off the light

# - POST /bedroom/light/1 => POST /GPIO/25/value/1, turn on the light

# - GET /bedroom/temperature => GET /devices/temp2/temperature/c, returns the temperature in celsius

#/bedroom/light = /GPIO/25/value

#/bedroom/temperature = /devices/temp2/temperature/c

 

#/livingroom/light = /devices/expander0/0

#/livingroom/brightness = /devices/adc/0/float

#/livingroom/temperature = /devices/temp0/temperature/c

 

#/weather/temperature = /devices/bmp/temperature/c

#/weather/pressure = /devices/bmp/pressure/hpa

 

【作用】

使得REST API看起来更尤优美一些，暂时未详细测试。