Actyx SDK

Actyx is a decentralized event database, streaming and processing engine that allows you to easily build local-first cooperative apps. It makes it easy to run distributed applications on multiple nodes. It is a piece of software that allows you to run your own apps on one or more edge devices and have these apps seamlessly communicate and share data with each other.

This crate defines the data types needed for communicating with Actyx and provides Rust bindings for the Actyx APIs. It also provides serialization instances for processing the events with differential-dataflow under the "dataflow" feature flag.

Examples

Below you find a full example using the EventService client that retrieves some events. Please adapt the queried tags to match your stored events in order to see output.

Note: this example needs the client feature to compile.

use actyx_sdk::{
  app_id, AppManifest, HttpClient,
  service::{EventService, Order, QueryRequest, QueryResponse},
};
use futures::stream::StreamExt;
use url::Url;

#[tokio::main]
pub async fn main() -> anyhow::Result<()> {
  // add your app manifest, for brevity we will use one in trial mode
  let app_manifest = AppManifest::new(
      app_id!("com.example.my-awesome-app"),
      "display name".into(),
      "0.1.0".into(),
      None,
  );

  // Url of the locally running Actyx node
  let url = Url::parse("http://localhost:4454")?;
  // create client for it
  let service = HttpClient::new(url, app_manifest).await?;

  // all events matching the given subscription
  // sorted backwards, i.e. youngest to oldest
  let mut events = service
      .query(QueryRequest {
          lower_bound: None,
          upper_bound: None,
          query: "FROM 'MyFish'".parse()?,
          order: Order::Desc,
      })
      .await?;

  // print out the payload of each event
  // (cf. Payload::extract for more options)
  while let Some(QueryResponse::Event(event)) = events.next().await {
      println!("{}", event.payload.json_value());
  }
  Ok(())
}

Feature flags

The default is to provide only the data types with serialization and deserialization support for serde. The following features can be enabled in addition:

• client: include HTTP client bindings using the reqwest crate
• dataflow: provide Abomonation instances for use with tools like Differential Dataflow
• arb: provide quickcheck::Arbitrary instances for common data types. This is useful for testing.