Quasar - A Soroban indexer

Quasar offers a GraphQL API for ledgers, transactions, contracts, operations and events among others written in Rust.

Currently built to handle a subset of the Stellar dataset.

Why?

Because those who will build on top of Soroban need easy access to complex data and for them to succeed they need to focus on their core value proposition not build custom data pipes every time they need processed data or event notifications.

Project Overview

Quasar, aims to be a robust Soroban indexer built on top of the extended Stellar core node implementation. The tool is designed to provide high-quality Web3 infrastructure to wallets and other interfaces that connect raw data to user experiences, offering access to the Soroban ecosystem with greater efficiency and reliability. You can also think of it as an extension to the Horizon API, what Horizon is to core Stellar data, Quasar is to the Soroban ecosystem. Quasar can be build standalone or be an extension to the existing Horizon API.

Prerequisites

• You need a running Stellar Core node.

docker run --rm -it -p "8000:8000" -p "8001:5432" --name stellar stellar/quickstart:latest --standalone --enable-soroban-rpc

• You also need a running Postgres instance for persistence, eg:

docker run --name quasar -e POSTGRES_PASSWORD=quasar -e POSTGRES_DB=quasar_development  -p 5432:5432 -v postgres-data:/var/lib/postgresql/data -d postgres

Setup

You will need a config file located in the path config/config.toml.

Here is an example:

quasar_database_url = "postgres://postgres:postgres@localhost:5432/quasar_development"
stellar_node_database_url = "postgres://stellar:<password>@localhost:8001/core"

[ingestion]
polling_interval = 5

[api]
host = "127.0.0.1"
port = 8000
depth_limit = 16
complexity_limit = 64

[metrics]
database_polling_interval = 5

Getting started

Install quasar from the releases page. Here is an example in Linux:

  curl -L https://github.com/eigerco/quasar/releases/download/<version>/quasar_indexer-x86_64-unknown-linux-gnu.tar.gz > quasar.tar.gz
  tar -xf quasar.tar.gz
  ./quasar_indexer

GraphQL Playground will be available at http://localhost:8000/. Prometheus metrics at http://localhost:8000/metrics.

Development

Clone the project

  git clone https://github.com/eigerco/quasar

Go to the project directory

  cd quasar

Run Tests

  cargo test

Start the server

  cargo run

Overview of features

• Ingestion of:
  • ledgers
  • accounts
  • transactions
  • operations
  • contracts
  • events
• GraphQL:
  • Playground IDE with documentation
  • sorting
  • filtering
  • pagination
  • relationships
• Prometheus metrics

Planned features

Handling of the full Stellar dataset

Currently Quasar supports working with a limited subset of the Stellar dataset. We plan to support the full dataset, so that Quasar can run alongside a Full Validator, in the future. This will allow Quasar to be used as a data source for Stellar applications.

GraphQL subscriptions

Subscriptions will allow clients to receive real-time updates from the indexer. For example a client can subscribe to a specific account and receive updates when the account's balance changes. This will be useful for building real-time applications.

Processing of more data

The current version of Quasar supports only basic data types. Not all of their fields are ingested and processed. Some relationships between entities are also missing. We plan to add support for:

• more Stellar data types
• missing fields in existing data types
• more relationships between entities
• aggregated data

More contract-specific GraphQL queries

We plan to add more GraphQL queries that are specific to Stellar contracts.

Access control

We plan to add access control to the GraphQL API. This will allow owners of the server to restrict access to certain data.

Contributing

Contributions are always welcome!

About Eiger

We are engineers. We contribute to various ecosystems by building low level implementations and core components. We built Quasar early in Sorobans development to help newcomers to the Stellar ecosystem. Contact us at hello@eiger.co Follow us on X/Twitter