docs

Chronicle

---

Chronicle in simple terms is an indexing software, indexing transactions and modules (Smart contract, Parachain, and so on) Events. Chronicle stores these data in a Postgress DB and renders these data using an GraphQL interface. Chronicle is designed to achieve high-performance and high-reliability in cloud deployments via a modular architecture, Developers can hand-pick modules to build whatever, seeing the components of the Chronicle as pieces of Legos.

The core reasons for building Chronicle are:

1. Exploring the possiblity for building a high-performance and high-reliability blockchain indexer.
2. Building a modular architecture that allows developers to hand-pick modules to build whatever they want.
3. Building an advanced software that intermidate rust engineers and learn from and contribute to.

This is nice to note that a good chuck of the development pratices and rust centered design patterns are inspired by the Substrate, Hyperbridge, and Rundler.

Chronicle is Divided into two main components:

1. Chronicle-Indexer: This is the core of the Chronicle, it is responsible for indexing transactions and modules (Smart contract, Parachain, and so on) Events.
2. Chronicle-GraphQL: This is the interface of the Chronicle, it is responsible for rendering the indexed data in a GraphQL interface. This is refered to as chronicle-server.

The code base is classified into:

1. Binary

   • Chronicle: this is the only binary crate in the code base, it is responsible for running the Chronicle. it is the entry point of the Chronicle, the main.rs file is located in the bin directory. It runs the chronicle-indexer and chronicle-server concurrently, Empowered with a CLI interference to control the Chronicle.

2. Crates

• Chronicle-Indexer: This is the core of the Chronicle, it is responsible for indexing transactions and modules (Smart contract, Parachain, and so on) Events.
• Chronicle-GraphQL: This is the interface of the Chronicle, it is responsible for rendering the indexed data in a GraphQL interface. This is refered to as chronicle-server.
• Chronicle-Primitives: This is a shared library that contains common utilities and data structures used across the Chronicle.
• Chronicle-Task: This implements a rules on how concurrent tasks should be executed in the Chronicle.