Recipes

This page includes some recipes for using the Python library to make custom programs with the utilities provided, perhaps combined with other libraries. See the Python library API page for a full API reference.

Note

You’ll need to create an API key to be able to use these recipes. See the Getting started page to begin. The following examples assume the API keys are set using environment variables, but they can be provided as arguments to the PiCloud class constructor.

Provisioning Pis

Provision a Pi

from hostedpi import PiCloud

cloud = PiCloud()

pi = cloud.create_pi('mypi', model=3, disk=10)

Provision some Pis

from hostedpi import PiCloud

cloud = PiCloud()

pis = [
    cloud.create_pi('mypi{}'.format(n), model=3, disk=10)
    for n in range(10)
]

Push button to provision a Pi

from hostedpi import PiCloud
from gpiozero import Button, LED

cloud = PiCloud()
btn = Button(2)
led = LED(3)

def make_pi():
    name = "helloworld"
    cloud.create_pi(name)
    led.on()

btn.when_pressed = make_pi

See a live demo at https://twitter.com/ben_nuttall/status/1300442981779025921

Note

This requires the gpiozero library.

Retrieving data about Pis

List all Pis

from hostedpi import PiCloud

cloud = PiCloud()

for name in cloud.pis:
    print(name)

List all Pis and their IPv6 address

from hostedpi import PiCloud

cloud = PiCloud()

for name, pi in cloud.pis.items():
    print(name, pi.ipv6_address)

Rebooting

Reboot all Pis

from hostedpi import PiCloud

cloud = PiCloud()

for pi in cloud.pis.values():
    pi.reboot()

Power on/off

Boot all Pis powered off

from hostedpi import PiCloud

cloud = PiCloud()

for pi in cloud.pis.values():
    if not pi.power:
        pi.on()

SSH

List SSH commands for all Pis

from hostedpi import PiCloud

cloud = PiCloud()

for pi in cloud.pis.values():
    print(pi.ipv4_ssh_command)

from hostedpi import PiCloud

cloud = PiCloud()

for pi in cloud.pis.values():
    print(pi.ipv6_ssh_command)

Write SSH config to a file

from hostedpi import PiCloud

cloud = PiCloud()

with open('config', 'w') as f:
    f.write(cloud.ssh_config)

Web

Retrieve the contents of the homepage

Note

Note that a web server must be installed on the Pi for the URL to resolve in a web browser, and an SSL certificate must be created for the https URL to resolve.

Print out:

from hostedpi import PiCloud
import requests

cloud = PiCloud()
pi = cloud.pis['somepi']

r = requests.get(pi.url)
print(r.text)

Save to a file:

from hostedpi import PiCloud
import requests

cloud = PiCloud()
pi = cloud.pis['somepi']

r = requests.get(pi.url)
with open('pi.html', 'w') as f:
    f.write(r.text)

Access a particular web location

Access data.json from the web server, and print out the message value:

from hostedpi import PiCloud
import requests

cloud = PiCloud()
pi = cloud.pis['somepi']

url = pi.url + '/data.json'
r = requests.get(url)
data = r.json()
print(data['message'])