iridis_message/
helper.rs

1use std::{collections::HashMap, sync::Arc};
2
3use crate::prelude::*;
4
5use arrow_array::*;
6use arrow_buffer::*;
7use arrow_data::*;
8use arrow_schema::*;
9
10/// Helper function to create a union field.
11pub fn make_union_fields(name: impl Into<String>, fields: Vec<Field>) -> Field {
12    Field::new(
13        name,
14        DataType::Union(
15            UnionFields::new(0..fields.len() as i8, fields),
16            UnionMode::Dense,
17        ),
18        false,
19    )
20}
21
22/// Helper function to unpack a union array.
23pub fn unpack_union(data: ArrayData) -> (HashMap<String, usize>, Vec<ArrayRef>) {
24    let (fields, _, _, children) = UnionArray::from(data).into_parts();
25
26    let map = fields
27        .iter()
28        .map(|(id, field)| (field.name().into(), id as usize))
29        .collect::<HashMap<String, usize>>();
30
31    (map, children)
32}
33
34/// Helper function to extract data from a union array.
35pub fn extract_union_data<T: ArrowMessage>(
36    field: &str,
37    map: &HashMap<String, usize>,
38    children: &[ArrayRef],
39) -> Result<T> {
40    T::try_from_arrow(
41        children
42            .get(
43                *map.get(field)
44                    .ok_or(eyre::eyre!("Field {} not found", field))?,
45            )
46            .ok_or(eyre::eyre!("Field {} not found", field))?
47            .into_data(),
48    )
49}
50
51/// Helper function to get the union fields of a message.
52pub fn get_union_fields<T: ArrowMessage>() -> Result<UnionFields> {
53    match T::field("").data_type() {
54        DataType::Union(fields, _) => Ok(fields.clone()),
55        _ => Err(eyre::eyre!("Expected Union data type")),
56    }
57}
58
59/// Helper function to create a union array.
60pub fn make_union_array(union_fields: UnionFields, children: Vec<ArrayRef>) -> Result<ArrayRef> {
61    UnionArray::try_new(
62        union_fields,
63        ScalarBuffer::from(vec![]),
64        Some(ScalarBuffer::from(vec![])),
65        children,
66    )
67    .map(|union| Arc::new(union) as ArrayRef)
68    .map_err(eyre::Report::msg)
69}
iridis_message/helper.rs

iridis_message/
helper.rs
