qwal 0.1.0

A disk baced Write Ahead Log that can functuin as a FIFO queue
Documentation 
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// Copyright 2021, The Tremor Team
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use std::convert::Infallible;

/// Represents a serializable entry in the write-ahead-log
pub trait Entry {
    type Output;
    type Error: std::error::Error;
    fn serialize(self) -> Result<Vec<u8>, Self::Error>;
    fn deserialize(data: Vec<u8>) -> Result<Self::Output, Self::Error>;
}

impl Entry for Vec<u8> {
    type Output = Vec<u8>;
    type Error = Infallible;
    fn serialize(self) -> Result<Vec<u8>, Self::Error> {
        Ok(self)
    }

    fn deserialize(data: Vec<u8>) -> Result<Self::Output, Self::Error> {
        Ok(data)
    }
}

impl Entry for &[u8] {
    type Output = Vec<u8>;
    type Error = Infallible;
    fn serialize(self) -> Result<Vec<u8>, Self::Error> {
        Ok(self.to_vec())
    }

    fn deserialize(data: Vec<u8>) -> Result<Self::Output, Self::Error> {
        Ok(data)
    }
}