iridis-message 0.4.0

iridis is a framework that lets you define and build dataflow applications with ease.
Documentation 
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//! This module contains the `ArrowMessage` triatt and its implementation for various types.

use std::sync::Arc;

use crate::prelude::*;

use arrow_array::*;
use arrow_data::*;
use arrow_schema::*;

/// Trait to represent a message that can be converted to and from an Arrow array.
pub trait ArrowMessage {
    /// Each message must declare how it's represented as an Arrow field.
    fn field(name: impl Into<String>) -> Field;

    /// Try to convert the message into an Arrow array.
    fn try_into_arrow(self) -> Result<ArrayRef>;

    /// Try to convert an Arrow array into the message.
    fn try_from_arrow(data: ArrayData) -> Result<Self>
    where
        Self: Sized;
}

impl<T> ArrowMessage for Option<T>
where
    T: ArrowMessage,
{
    fn field(name: impl Into<String>) -> Field {
        T::field(name).with_nullable(true)
    }

    fn try_into_arrow(self) -> Result<ArrayRef> {
        match self {
            Some(value) => value.try_into_arrow(),
            None => Ok(Arc::new(NullArray::new(0)) as ArrayRef),
        }
    }

    fn try_from_arrow(data: ArrayData) -> Result<Self>
    where
        Self: Sized,
    {
        match data.data_type() {
            DataType::Null => Ok(None),
            _ => T::try_from_arrow(data).map(|value| Some(value)),
        }
    }
}

impl<T> ArrowMessage for PrimitiveArray<T>
where
    T: ArrowPrimitiveType,
{
    fn field(name: impl Into<String>) -> Field {
        Field::new(name, T::DATA_TYPE, false)
    }

    fn try_into_arrow(self) -> Result<ArrayRef> {
        Ok(Arc::new(self) as ArrayRef)
    }

    fn try_from_arrow(data: ArrayData) -> Result<Self>
    where
        Self: Sized,
    {
        Ok(PrimitiveArray::from(data))
    }
}

macro_rules! impl_arrow_field {
    ($type:ty, $data_type:expr, $array_type:ty) => {
        impl ArrowMessage for $type {
            fn field(name: impl Into<String>) -> Field {
                Field::new(name, $data_type, false)
            }

            fn try_into_arrow(self) -> Result<ArrayRef> {
                Ok(Arc::new(<$array_type>::from(vec![self])) as ArrayRef)
            }

            fn try_from_arrow(data: ArrayData) -> Result<Self>
            where
                Self: Sized,
            {
                let array = <$array_type>::from(data);
                match array.len() {
                    0 => Err(eyre::eyre!("Array is empty")),
                    _ => Ok(array.value(0)),
                }
            }
        }
    };
}

impl_arrow_field!(u8, DataType::UInt8, UInt8Array);
impl_arrow_field!(u16, DataType::UInt16, UInt16Array);
impl_arrow_field!(u32, DataType::UInt32, UInt32Array);
impl_arrow_field!(u64, DataType::UInt64, UInt64Array);
impl_arrow_field!(i8, DataType::Int8, Int8Array);
impl_arrow_field!(i16, DataType::Int16, Int16Array);
impl_arrow_field!(i32, DataType::Int32, Int32Array);
impl_arrow_field!(i64, DataType::Int64, Int64Array);
impl_arrow_field!(f32, DataType::Float32, Float32Array);
impl_arrow_field!(f64, DataType::Float64, Float64Array);
impl_arrow_field!(bool, DataType::Boolean, BooleanArray);

impl ArrowMessage for String {
    fn field(name: impl Into<String>) -> Field {
        Field::new(name, DataType::Utf8, false)
    }

    fn try_into_arrow(self) -> Result<ArrayRef> {
        Ok(Arc::new(StringArray::from(vec![self])) as ArrayRef)
    }

    fn try_from_arrow(data: ArrayData) -> Result<Self>
    where
        Self: Sized,
    {
        let array = StringArray::from(data);
        match array.len() {
            0 => Err(eyre::eyre!("Array is empty")),
            _ => Ok(array.value(0).into()),
        }
    }
}

impl ArrowMessage for StringArray {
    fn field(name: impl Into<String>) -> Field {
        Field::new(name, DataType::Utf8, false)
    }

    fn try_into_arrow(self) -> Result<ArrayRef> {
        Ok(Arc::new(self) as ArrayRef)
    }

    fn try_from_arrow(data: ArrayData) -> Result<Self>
    where
        Self: Sized,
    {
        Ok(StringArray::from(data))
    }
}