virtx 0.1.2

//! [`Failure`], the one error shape every [`Client`](crate::protocol::Client) method returns.

use crate::protocol::Error;

/// Why a call produced no result.
///
/// A refusal is about the call (retry or report it); a broken channel is about the
/// session, and every later call will fail the same way.
#[derive(Debug)]
pub enum Failure {
    /// The server answered `error`. Branch on [`code`](Error::code): only
    /// [`TIMED_OUT`](Error::TIMED_OUT) is worth retrying, with more time.
    Refused(Error),

    /// The channel or the server process failed; no answer will come.
    Broken(anyhow::Error),
}

impl Failure {
    /// The protocol code for a refusal; `None` for a broken channel.
    pub fn code(&self) -> Option<i64> {
        match self {
            Failure::Refused(error) => Some(error.code),
            Failure::Broken(_) => None,
        }
    }

    pub(crate) fn broken(what: impl Into<String>) -> Failure {
        Failure::Broken(anyhow::Error::msg(what.into()))
    }
}

impl std::fmt::Display for Failure {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        match self {
            Failure::Refused(error) => write!(f, "the console server refused: {error}"),
            Failure::Broken(e) => write!(f, "the console channel broke: {e}"),
        }
    }
}

impl std::error::Error for Failure {
    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
        match self {
            Failure::Refused(error) => Some(error),
            Failure::Broken(e) => Some(e.as_ref()),
        }
    }
}

impl From<Error> for Failure {
    fn from(error: Error) -> Failure {
        Failure::Refused(error)
    }
}