pyth-network_pyth-crosschain/pyth-rng/src/api.rs

use {
    crate::{
        ethereum::PythContract,
        state::HashChainState,
    },
    axum::{
        http::StatusCode,
        response::{
            IntoResponse,
            Response,
        },
    },
    ethers::core::types::Address,
    std::sync::Arc,
};
pub use {
    index::*,
    revelation::*,
};

mod index;
mod revelation;

/// The state of the randomness service for a single blockchain.
#[derive(Clone)]
pub struct ApiState {
    /// The hash chain(s) required to serve random numbers for this blockchain
    pub state:            Arc<HashChainState>,
    /// The EVM contract where the protocol is running.
    pub contract:         Arc<PythContract>,
    /// The EVM address of the provider that this server is operating for.
    pub provider_address: Address,
}


pub enum RestError {
    /// The caller passed a sequence number that isn't within the supported range
    InvalidSequenceNumber,
    /// The caller requested a random value that can't currently be revealed (because it
    /// hasn't been committed to on-chain)
    NoPendingRequest,
    /// The server cannot currently communicate with the blockchain, so is not able to verify
    /// which random values have been requested.
    TemporarilyUnavailable,
    /// A catch-all error for all other types of errors that could occur during processing.
    Unknown,
}

impl IntoResponse for RestError {
    fn into_response(self) -> Response {
        match self {
            RestError::InvalidSequenceNumber => (
                StatusCode::BAD_REQUEST,
                "The sequence number is out of the permitted range",
            )
                .into_response(),
            RestError::NoPendingRequest => (
                StatusCode::FORBIDDEN,
                "The random value cannot currently be retrieved",
            )
                .into_response(),
            RestError::TemporarilyUnavailable => (
                StatusCode::SERVICE_UNAVAILABLE,
                "This service is temporarily unavailable",
            )
                .into_response(),
            RestError::Unknown => (
                StatusCode::INTERNAL_SERVER_ERROR,
                "An unknown error occurred processing the request",
            )
                .into_response(),
        }
    }
}