Crate actyx_sdk

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Latest Version Rust Documentation

§ 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:

Modules§

language
legacy
service
types
Types that you may want to use in describing the event payload data

Macros§

app_id
Macro for constructing an AppId literal.
arcval_scalar
Helper macro to create interned string types
fish_name
Macro for constructing a FishName literal.
semantics
Macro for constructing a Semantics literal.
source_id
Macro for constructing a SourceId literal.
tag
Macro for constructing a Tag literal.
tags
Macro for constructing a set of Tag values.

Structs§

AppId
The app ID denotes a specific app (sans versioning)
AppManifest
App manifest used for requesting a bearer token via the API. For more information see the docs.
Event
Events are delivered in this envelope together with their metadata
EventKey
The sort key of an event
HttpClient
LamportTimestamp
A logical timestamp taken from a Lamport clock
Metadata
Metadata attached to an event that can be used for filtering.
NodeId
The Actyx node identifier
Offset
Event offset within a stream
OffsetMap
Multi-dimensional cursor for event streams: an OffsetMap describes the set of events given by the event streams of each included source up to the associated Offset.
OffsetOrMin
Event offset within a SourceId’s stream or MIN value
Opaque
A ref-counted slice of memory holding a compact binary representation of an event payload
Payload
Compact binary storage of events created when they are received
StreamId
The unique identifier of a single event stream emitted by an Actyx node
StreamNr
Stream number. Newtype alias for u64
Tag
A Tag that semantically characterises an event.
TagSet
A set of tags in canonical iteration order
Timestamp
Microseconds since the UNIX epoch, without leap seconds and in UTC
Url
A parsed URL record.

Enums§

ParseError