pyth-crosschain/price_service/server

Pyth Price Service

** Pyth price service is deprecated. Please use Hermes instead. **

The Pyth price service is a webservice that listens to the Wormhole Network for Pyth price updates and serves them via a convenient web API. The service allows users to easily query for recent price updates via a REST API, or subscribe to a websocket for streaming updates. Price service JS client connects to an instance of the price service in order to fetch on-demand price updates.

Wormhole Spy

The price service depends on a Wormhole Spy to stream Pyth messages from the Wormhole Network to it. The spy is a Wormhole component that listens to the Wormhole verified messages from the Wormhole Network peer-to-peer network; then, it streams the messages that are coming from certain emitters (e.g., Pyth data emitters) to its subscribers.

The price service subscribes to the spy to fetch all verified prices coming from the Pyth data sources. The Pyth data sources should be defined in SPY_SERVICE_FILTERS environment variable as a JSON array.

Run

This repository contains testnet and mainnet docker-compose files to run both the price service and spy. To run the mainnet docker compose file run the following command:

docker compose -f docker-compose.mainnet.yaml up

Now your own instance of the price service is up and running! Running the following command should give you the Pyth price of ETH/USD :

curl localhost:4200/api/latest_price_feeds?ids[]=0xff61491a931112ddf1bd8147cd1b641375f79f5825126d665480874634fd0ace

If everything is working, you should get an output like this :

[{"ema_price":{"conf":"52359655","expo":-8,"price":"169041770000","publish_time":1675365813},"id":"ff61491a931112ddf1bd8147cd1b641375f79f5825126d665480874634fd0ace","price":{"conf":"64041644","expo":-8,"price":"167043958356","publish_time":1675365813}}]

The compose files use a public release of Pyth price service and spy. If you wish to change the price service you should:

1. Build an image for using it first according to the section below.
2. Change the price service image to your local docker image (e.g., pyth_price_server)

Self-Hosting

If you would like to host your own instance of the price service, we recommend running the process on a 4 core machine with 4 GB of RAM. We also recommend using a host like Latitude or Hetzner and avoiding cloud service providers like AWS in order to reduce the cost. The price service participates in a peer-to-peer network which can use a lot of bandwidth. Cloud hosts like AWS charge high fees for bandwidth, which makes running the service much more expensive than necessary. Using one of the recommended hosts above should cost $10-50 / month.

Build an image

Build the image from the repo root like below. It will create a local image named pyth_price_server.

$ docker buildx build -f tilt_devnet/docker_images/Dockerfile.lerna -t lerna .
$ docker buildx build -f price_service/server/Dockerfile -t pyth_price_server .

If you wish to build price service without docker, please follow the instruction of the price service Dockerfile

Known Issues

The spy sometimes fails to connect to the peer-to-peer network on initialization. If this happens, the price service will not be able to retrieve any data. You can fix this problem by quitting, removing the containers from Docker, then restarting both containers. Simply stopping and starting the services tends not to work.