nref / gpio

A web service for Raspberry Pi GPIO

gpio

A web service for Raspberry Pi GPIO

Features

• Access GPIO pins via GET and POST

  • Using BCM (Broadcom) GPIO pin identifiers.
    • not using board identifiers
    • See http://pinout.xyz/

• Optional heartbeat fail-safe

  • Turns all pins OFF if it is not called within 2 seconds.

Requirements

• A Raspberry Pi
• Python3
• gpiozero

Running

> git clone https://github.com/slater1/gpio
> cd gpio
> make run
python3 -u main.py >> main.log 2>&1 &
tail -n 0 -f main.log
Server up at :8001

Stopping

> cd gpio
> make stop
kill 23028

Configuration

See HOST and PORT in the makefile

Routes

GET

/pin/{id}

Get the value of the given BCM (Broadcom) GPIO pin identifier. 0 means OFF, 1 means ON.

Examples:

curl http://raspberrypi:8001/pin/1
0

curl http://raspberrypi:8001/pin/2
1

/pins

Return all set GPIOs

Example:

GET http://raspberrypi:8001/pins
[(1, 0), (2, 1), (3, 0)] # GPIOs 1 and 3 are off, 2 is on

/

Same as /pins

POST

/heartbeat/enable

Enable the heartbeat check.

When the heartbeat check is enabled, the /heartbeat endpoint must be POSTed to at least once every 2 seconds. If not, all previously accessed pins are turned OFF.

Example:

curl --request POST http://zerow2:8001/heartbeat/enable
ok

/heartbeat/disable

Disable the heartbeat check.

Example:

curl --request POST http://zerow2:8001/heartbeat/disable
ok

/heartbeat

Update the heartbeat.

When the heartbeat check is enabled, this endpoint must be POSTed to at least once every 2 seconds. If not, all previously accessed pins are turned OFF.

Example:

curl --request POST http://zerow2:8001/heartbeat
ok

/pin/{id}/on

Turn the given pin ON

/pin/{id}/off

Turn the given pin OFF

Debugging (hot-reload):

> cd gpio
> make hot
./hott.sh "python3 -u main.py" ">> main.log 2>&1 &" *.py &
touch main.log
tail -n 0 -f main.log
python3 -u main.py >> main.log 2>&1 &
Server up at :8001

Testing:

With service running (via make run or make hot:

> cd gpio
> make test

# test pins
curl http://raspberrypi:8001/pins
[]
curl --request POST http://raspberrypi:8001/pin/1/on
ok
curl --request POST http://raspberrypi:8001/pin/2/on
ok
curl http://raspberrypi:8001/pin/1
1
curl http://raspberrypi:8001/pin/2
1
curl http://raspberrypi:8001/pins
[(1, 1), (2, 1)]
curl --request POST http://raspberrypi:8001/pin/1/off
ok
curl --request POST http://raspberrypi:8001/pin/2/off
ok
curl http://raspberrypi:8001/pin/1
0
curl http://raspberrypi:8001/pin/2
0
curl http://raspberrypi:8001/pins
[(1, 0), (2, 0)]
curl http://raspberrypi:8001/pin/3
0
curl http://raspberrypi:8001/pins
[(1, 0), (2, 0), (3, 0)]
# test heartbeat
curl --request POST http://raspberrypi:8001/heartbeat/enable
ok
curl --request POST http://raspberrypi:8001/heartbeat
ok
curl --request POST http://raspberrypi:8001/heartbeat
ok
curl --request POST http://raspberrypi:8001/heartbeat
ok
curl --request POST http://raspberrypi:8001/heartbeat
ok
curl --request POST http://raspberrypi:8001/pin/1/on
ok
# Should be 1
curl http://raspberrypi:8001/pin/1
1
sleep 3
# Should be 0
curl http://raspberrypi:8001/pin/1
0
curl --request POST http://raspberrypi:8001/heartbeat/disable
ok
curl --request POST http://raspberrypi:8001/pin/1/on
ok
# Should be 1
curl http://raspberrypi:8001/pin/1
1
sleep 3
# Should be 1
curl http://raspberrypi:8001/pin/1
1