Crate slung 

Slung Rust SDK

An abstraction library for interacting with the Slung runtime.

Quickstart

Add to your rust project’s Cargo.toml:

[dependencies]
slung = "0.1.0"

And then at the top of your module:

use slung::prelude::*;

Example

Here’s a basic anomaly detection example:

use slung::prelude::*;

#[main]
fn main() -> Result<()> {
    // Subscribe to live stream updates.
    let handle = query_live("AVG:temp:[sensor=1]")?;
    poll_handle(handle, on_event, 100.0)?;

    Ok(())
}

fn on_event(event: Event, alert_threshold: f64) -> Result<()> {
    if event.value > alert_threshold {
        println!("event timestamp={} value={}", event.timestamp, event.value);
        for producer in event.producers {
            writeback_ws(producer, "ALERT: threshold exceeded")?;
        }
    }

    Ok(())
}

Query Syntax

OP:SERIES:[TAGS]:[RANGE]

• RANGE is optional
• OP: AVG, MIN, MAX, SUM, COUNT
• TAGS: AND, OR, NOT
• RANGE: [start_time,end_time]. Timestamps in microseconds. Also supports sec, min, hour, day, week (short & plural forms apply).

License

Unlike the root project, this SDK is licensed under the MIT License - see the LICENSE file for details.

Modules

prelude

Common imports for workflow handlers.

Structs

Avg

Running average state.

Event

Event payload returned by host polling.

Enums

PollState

Polled aggregate state variants.

WritebackMethod

HTTP method mapping expected by the host writeback API.

Functions

free_handle

Free a live query handle on the host.

poll_handle

Poll a live query forever and invoke callback for each received event.

poll_handle_state

Poll a live query once and decode aggregate state if available.

query_history

Execute a historical aggregation query and return the aggregate value.

query_live

Register a live query and return its host handle.

unix_micros

Return the current Unix epoch timestamp in microseconds.

write_event

Write a new event to the host.

writeback_http

Send an HTTP writeback request through the host.

writeback_ws

Write back text data to a websocket producer destination.

Type Aliases

QueryHandle

Opaque handle returned by live-query registration.