Streams

Every device variable has a stream attached to it. A stream is a complete history of that variable, every change that occurred and at what time, since the variable was created.

Let's say your device sets a variable temperature after every 10 seconds like this:

Arduino

Grandeur::Project project;
Grandeur::Device device;
unsigned long current = millis();
 
void setup() {
    project = grandeur.init(API_KEY, DEVICE_TOKEN);
    device = project.device(DEVICE_ID);
}
 
void loop() {
    if(millis() - current > 10000) { // Runs if-block after every 10 seconds.
        double temperature = readTemperatureFromGPIO();
        device.data().set("temperature", temperature);
        current = millis();
    }
 
    project.loop();
}

If you get the temperature variable, here's how the result shows:

Python

project = grandeur.init(API_KEY, DEVICE_TOKEN);
device = project.device(DEVICE_ID);
 
print(device.data().get("temperature"));
# Prints:
# {
#    code: "DEVICE-DATA-FETCHED",
#    data: 30.6,
#    logs: [{ timestamp: "2022-01-01T16:00:00.000Z", data: 30.6 }, { timestamp: "2022-01-01T16:00:10.000Z", data: 31.2 }, { timestamp: "2022-01-01T16:00:20.000Z", data: 31.8 }, { timestamp: "2022-01-01T16:00:30.000Z", data: 32.4 }, { timestamp: "2022-01-01T16:00:40.000Z", data: 33 }, ...]
# }

When you delete a variable, you also delete its stream.

Writing queries Add to a stream