Juno is a Cosmos Hub blockchain data aggregator and exporter that provides the ability for developers and clients to query for indexed chain data.

• Juno
  • Table of Contents
  • Background
  • Versions
  • Install
  • Usage
  • Schemas
  • Future Improvements
  • Contributing
  • License

Juno is a Cosmos Hub data aggregator and exporter. In other words, it can be seen as an ETL layer atop of the Cosmos Hub. It improves the Hub's data accessibility by providing an indexed PostgreSQL database exposing aggregated resources and models such as blocks, validators, pre-commits, transactions, and various aspects of the governance module. Juno is meant to run with a GraphQL layer on top so that it even further eases the ability for developers and downstream clients to answer queries such as "what is the average gas cost of a block?" while also allowing them to compose more aggregate and complex queries.

🎉 Fission Labs publishes a public GraphQL API for the Cosmos Hub that can be found here 🎉

• v0.0.5 - v0.0.6
  • Network: cosmoshub-3
• v0.0.4
  • Network: cosmoshub-2
• v0.0.1 - v0.0.3:
  • Network: cosmoshub-1

Juno takes a simple configuration. It needs to only know about a PostgreSQL database instance and a Tendermint RPC node.

Example:

rpc_node = "<rpc-ip/host>:<rpc-port>"
client_node = "<client-ip/host>:<client-port>"

[database]
host = "<db-host>"
port = <db-port>
name = "<db-name>"
user = "<db-user>"
password = "<db-password>"
ssl_mode = "<ssl-mode>"

To install the binary run make install.

Note: Requires Go 1.13+

Juno internally runs a single worker that consumes from a single queue. The queue contains block heights to aggregate and export to a PostgreSQL database. Juno will start a new block even listener where for each new block, it will enqueue the height. A worker listens for new heights and queries for various data related to the block height to persist. For each block height, juno will persist the block, the validators that committed/signed the block, all the pre-commits for the block and the transactions in the block.

In addition, it will also sync missing blocks from --start-height to the latest known height.

$ juno /path/to/config.toml [flags]

The schema definitions are contained in the schema/ directory. Note, these schemas are not necessarily optimal and are subject to change! However, feel free to fork this tool and expand upon the schemas as you see fit. Any tweaks will most likely require adjustments to the database wrapper.

• Unit and integration tests
• Persist governance proposals and tallies
• Improve the db migration process
• Implement better retry logic on failed queries
• Implement a docker-compose setup that allows for complete bootstrapping
• Improve modularity and remove any assumptions about the origin chain so Juno can sync with any Tendermint-based chain

Contributions are welcome! Please open an Issues or Pull Request for any changes.

MPL 2.0