Gohan Razuberi

What it is?

It's an REST service to manage Raspberry PI GPIOs. It is build on top of Gohan framework.

It aims to provide simple REST API to manage devices connected to RPi via GPIO pins.

It uses go-rpi library for gpios and supports same rpi version as this library.

How to run it

1. Install go on RasPi (http://dave.cheney.net/2015/09/04/building-go-1-5-on-the-raspberry-pi)
2. Install gohan (http://gohan.cloudwan.io/gohan/installation.html)
3. Install go-rpi: go get github.com/stianeikeland/go-rpio
4. Run: go run razuberi.go srv --config-file config.yaml
5. Voila! REST api is running on http://localhost:9091.

You can use keystone for authorization and authentication. Default config use fake keystone, which provides no security.

Check gohan docs for more info.

How to use it

With default config you can use gohan client to connect to the server.

1. source gohan.rc
2. gohan client gpio_output create --gpio_pin {pin_no} to create gpio resource. You can specify optional values like --name or --is_up.
3. gohan client gpio_output set --is_up true {pin_uuid or name} to set HIGH on given GPIO
4. gohan client gpio_output set --is_up false {pin_uuid or name} to set LOW on given GPIO

See schema.yaml for details about API.

You can also use CURL for direct access to API.

1. Acquire keystone token (for fake keystone this is always admin_token)
2. curl -H X-Auth-Token:{keystone_token} http://localhost:9091/v1.0/gpio_outputs - list of gpios.

Gohan API support normal actions like POST, PUT, DELETE.

If you don't need auth and don't use gohan client you can turn off keystone at all in config.yaml. gohan client requires at least fake keystone.

Default configuration uses sqlite3 but you can use also MySQL. See gohan docs for all posible configuration options

Example

Full example of lighting up a LED connected to pin 26.

# gohan client gpio_output create --name led26 --gpio_pin 26
+-----------+--------------------------------------+
| PROPERTY  |                VALUE                 |
+-----------+--------------------------------------+
| gpio_pin  | 26                                   |
| id        | eb2ebc72-21ba-459f-8ae0-fa0acaa94c79 |
| is_up     | false                                |
| name      | led26                                |
| tenant_id | fc394f2ab2df4114bde39905f800dc57     |
+-----------+--------------------------------------+
# gohan client gpio_output set --is_up true led26
+-----------+--------------------------------------+
| PROPERTY  |                VALUE                 |
+-----------+--------------------------------------+
| gpio_pin  | 26                                   |
| id        | eb2ebc72-21ba-459f-8ae0-fa0acaa94c79 |
| is_up     | true                                 |
| name      | led26                                |
| tenant_id | fc394f2ab2df4114bde39905f800dc57     |
+-----------+--------------------------------------+
# echo 'Led is now lit up'
# gohan client gpio_output set --is_up false led26
+-----------+--------------------------------------+
| PROPERTY  |                VALUE                 |
+-----------+--------------------------------------+
| gpio_pin  | 26                                   |
| id        | eb2ebc72-21ba-459f-8ae0-fa0acaa94c79 |
| is_up     | false                                |
| name      | led26                                |
| tenant_id | fc394f2ab2df4114bde39905f800dc57     |
+-----------+--------------------------------------+
# echo 'And now it is not'

TODO

• Manage also GPIO inputs (for now only outputs are available)
• Some higher level resources for most popular GPIO devices (like RGB Led or Motor).
• PWM support (not supported by go-rpi :( )