A REST API for controlling CHIP GPIO
Manual:
For Python2.7:
sudo apt-get update sudo apt-get install git build-essential python-dev python-pip flex bison python-flask -y git clone https://github.com/xtacocorex/chip_python_aREST.git cd chip_python_aREST sudo python setup.py install
For Python3:
sudo apt-get update sudo apt-get install git build-essential python3-dev python3-pip flex bison python-flask -y git clone https://github.com/xtacocorex/chip_python_aREST.git cd chip_python_aREST sudo python3 setup.py install
CHIP_IO is required to use this library, code and instructions are here: https://github.com/xtacocorex/CHIP_IO Scripts using this library will need to be run with root permissions (sudo or started at boot by init script).
This library is also available on pypi and can be installed via pip/pip3.:
# Python2 sudo pip install chip-python-aREST # Python3 sudo pip3 install chip-python-aREST
Example Script
The following is an example script that details a basic way to instantiate the REST API on your CHIP:
import CHIP_aREST.aREST as aREST
# Setup the id
# The id is a special identifier for your CHIP
aREST.set_id('5gad42')
# Setup the name
# The name can be anything you want
aREST.set_name("My Local CHIP")
# Setup the hardware type
# Not really needed until CHIP_IO get CHIP Pro support
aREST.set_hardware("chip")
# This is where any variables and functions would be setup
# Start the API
# Debug can be turned on/off
# Keep the host 0.0.0.0 to allow for local network access
# Port can be whatever you want it to be
aREST.RestApp(host="0.0.0.0"<Plug>PeepOpenort=3000,debug=True)
The API also supports user specified variables and functions:
# First create the variable
temperature = 25.2
# Then add it to the API
aREST.variable("temperature",temperature)
# For funtions, we need to define it first
# Functions can have arguments and they can be fed in with url parameters
def myfunction():
# you can do whatever you want here
# CHIP_IO Specific calls
# crazy math
# or in this case
return "myfunction was called, howdy!"
# Now we add it to the API
# Make sure you don't add the () to the function
aREST.function("functiontest",myfunction)
Cloud features TBD.
Example scripts are found in the examples folder. They are also installed into /usr/local/bin/.
For local instances of the API, you can access the CHIP via:
http://192.168.0.5:3000/
Replace the IP address with the one for your CHIP. If you have avahi installed on your CHIP, you can replace the IP address with <hostname>.local.
All of the REST API are detailed in the tables below. Note the HTTP Method used for the call. Not everything uses a normal HTTP GET method.
If you use a web browser to send the URL to the CHIP, you are limited to the GET method.
The curl program installed in Linux or MacOS/OS X can be used to test the API:
curl -X GET http://chipdev.local:3000/digital/csid0/1 curl -X GET http://chipdev.local:3000/temperature curl -X PUT http://chipdev.local:3000/temperature?value=-24.2
Basics
Method Command Description GET / Basic Info GET /id Basic Info GET /debug Dump all data GET /<variablename> Get value of <variablename> DELETE /<variablename> Delete <variablename> PUT, POST /<variablename>?value=<value> Set <variablename> to <value> GET /<functionname> Get value of <functionname> GET /<functionname>?value=<value> Get value of <functionname> with <value> as input GET /version Get current CHIP_IO version
GPIO
Method Command Description GET, PUT, POST /digital/<pinname>/[0,1] Digital Write 0 or 1 to <pinname> GET /digital/<pinname> Digital Read <pinname> GET /digital/<pinname>/r Digital Read <pinname> GET /digital/cleanup Cleanup all GPIO Pins GET /digital/cleanup/<pinname> Cleanup only GPIO Pin: <pinname>
PWM
Method Command Description GET /pwm/0/start?duty_cycle=[0.0-100.0]&frequency=<frequency> Start PWM0 with duty cycle and frequency. duty_cycle and frequency are optional, they default to 25.0% and 200.0 GET /pwm/0/stop Stop PWM0 GET /pwm/0/cleanup Cleanup PWM0 GET, PUT, POST /pwm/0/duty_cycle/[0.0-100.0] Change PWM0 Duty Cycle GET, PUT, POST /pwm/0/frequency/<frequency> Change PWM0 Frequency
Software PWM
Method Command Description GET /softpwm/<pinname>/start?duty_cycle=[0.0-100.0]&frequency=<frequency> Start SoftPWM on <pinname> with duty cycle and frequency. duty_cycle and frequency are optional, they default to 25.0% and 35.0 GET /softpwm/<pinname>/stop Stop SoftPWM on <pinname> GET /softpwm/<pinname>/cleanup Cleanup SoftPWM on <pinname> GET, PUT, POST /softpwm/<pinname>/duty_cycle/[0.0-100.0] Change SoftPWM Duty Cycle on <pinname> GET, PUT, POST /softpwm/<pinname>/frequency/<frequency> Change SoftPWM Frequency on <pinname>
LRADC
Method Command Description GET, PUT, POST /analog/sample_rate/[32.25,62.5,125,250] Set LRADC Sample Rate to 32.25, 62.5, 125, or 250 GET /analog/sample_rate Get currrent LRADC Sample Rate GET /analog/scale_factor Get LRADC Scale Factor GET /analog/raw/[0,1] Get raw LRADC output for channel 0 or 1 GET /analog/full/[0,1] Get full LRADC output for channel 0 or 1 Utilities
Method Command Description GET, PUT, POST /1v8_pin/enable/[1.8,2.0,2.6,3.3] Enable 1.8V Pin to output 1.8, 2.0, 2.6, or 3.3V GET /1v8_pin/voltage Get currrent 1.8V Pin voltage setting GET /1v8_pin/disable Disable 1.8V Pin GET /unexport_all Backup function to unexport all GPIO
Marco Schwartz for the original pi-aREST node.js code that was used as a basis for this code. (https://github.com/marcoschwartz/pi-aREST)
CHIP Python aREST by Robert Wolterman, released under the MIT License.