[Solved] How to read events from cloud?

Cloud
1

Hi there,

Newbie here. I successfully run electron and I can see temp coming from the device. I also use iOS app and I get useful information from my device.

Now, I tried to use webhook and I configured it but it stops working time to time. My question is, is there a way that I can read events from the cloud? I’ve read the API section and I did not understand anything. Can I write my own code in C or C# or Python in order to pull those event information from the particle cloud? Is there any tutorial on that?

Sorry for my basic question. My background is not software.

Thanks,

2

If you want to catch events in C# or Python I guess googling SSE (server sent events) will render a load of results since it's a concept not unique to Particle devices.
However, there already are some threads about SSE here
e.g.

For C# you could still use the discontinued SDK here
https://docs.particle.io/reference/discontinued/windows/#events-sub-system

3

Happy to show my working code hooking into the SSE Stream, my question was tagged above by @ScruffR

Got it working in C#.

1 Like
4

Thanks to both of you.
I have one more question. I can easily get diagnostics and SIM Card information using:

curl “https://api.particle.io/v1/diagnostics/DeviceID/update?access_token=1234”

Now, I’m using Electron to publish Temp. How do I get the temp value using curl? This command: curl “https://api.particle.io/v1/devices/DeviceID/events/temp?access_token=1234” does not work for me.

Thanks again,

5

You’d need to register that variable via Particle.variable(), but that’s not an event.
The docs do help with such questions
https://docs.particle.io/reference/device-os/firmware/electron/#particle-variable-

6

Thanks.
Yeah, I’ve read about it and looks very interesting. When I register my variables in the void setup, do I need to keep my electron active and connected? Or can I use System.sleep(SLEEP_MODE_DEEP,600) in the loop?

7

Variables request information from a device, as such, it needs to be awake to respond.
SSEs shout information through the cloud, as such, someone needs to be listening to hear it.

8

Thanks for the information. I’ve read about Events and variables and I could easily implement it. Here is what I’m doing:

Using Cloud APIs, I wrote a Python code to get the diagnostics info as well as the SIM info and post them to my MQTT Broker. Then I’m using Node-Red to display the information. It’s works great!

Now I’m stuck on how to read my sensor info while keeping the board in deep sleep.
If I use Variable to post, the board needs to be awake and hence I can not use System Deep Sleep.
If I use publish and then listen to events, with curl "https://api.particle.io/v1/devices/XXXX/events/Distance?access_token=XXXX" then I can’t catch the event say every 5 minutes. My python is not able to catch streams of events.

Is there another way that I can read my sensor value AND use deep sleep? I don’t use any integrations. I have my own broker.

Thanks!

9

[Update] I solved it. Here is a the python code if anyone is interested:

import json
import pprint
import sseclient

def with_urllib3(url):
    """Get a streaming response for the given event feed using urllib3."""
    import urllib3
    http = urllib3.PoolManager()
    return http.request('GET', url, preload_content=False)

def with_requests(url):
    """Get a streaming response for the given event feed using requests."""
    import requests
    return requests.get(url, stream=True)

url = 'https://api.particle.io/v1/devices/XXX/events/EVENT_NAME?access_token=XXX'
response = with_urllib3(url)  # or with_requests(url)
client = sseclient.SSEClient(response)

for event in client.events():
    pprint.pprint(json.loads(event.data))

You will need sseclient-py and ssclient.
Thanks,

Reference: https://pypi.org/project/sseclient-py/

1 Like