abci-rs

A Rust crate for creating ABCI applications.

ABCI Overview

ABCI is the interface between Tendermint (a state-machine replication engine) and your application (the actual state machine). It consists of a set of methods, where each method has a corresponding Request and Response message type. Tendermint calls the ABCI methods on the ABCI application by sending the Request messages and receiving the Response messages in return.

ABCI methods are split across 4 separate ABCI connections:

• Consensus Connection: InitChain, BeginBlock, DeliverTx, EndBlock, Commit
• Mempool Connection: CheckTx
• Info Connection: Info, SetOption, Query
• Snapshot Connection: ListSnapshots, LoadSnapshotChunk, OfferSnapshot, ApplySnapshotChunk

Additionally, there is a Flush method that is called on every connection, and an Echo method that is just for debugging.

To know more about ABCI protocol specifications, go to official ABCI documentation.

Usage

Add abci-rs in your Cargo.toml's dependencies section:

[dependencies]
abci-rs = "0.11"

Each ABCI application has to implement four core traits corresponding to all four ABCI connections, Consensus, Mempool, Info and Snapshot.

Note: Implementations of these traits are expected to be Send + Sync and methods take immutable reference of self. So, internal mutability must be handled using thread safe (Arc, Mutex, etc.) constructs.

Synchronous and asynchronous APIs

abci-rs supports both, synchronous and asynchronous APIs (using sync-api and async-api cargo features). At least one of these features should be enabled. By default, both, sync-api and async-api, features are enabled.

Async runtimes

abci-rs also supports multiple async runtimes. These different runtimes can be enabled by using cargo features use-async-std, use-smol or use-tokio. Only one runtime can be enabled at a time. Compilation will fail if more than one runtime is enabled or none of them are enabled. By default, use-tokio feature is enabled.

Examples

Example ABCI applications can be found in examples/sync-counter.rs (using sync_api) and examples/async-counter.rs (using async_api).

Documentation

• master
• release

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE)
• MIT license (LICENSE-MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.