Struct DoraArray 

pub struct DoraArray(/* private fields */);

A dora payload: an Apache Arrow array owned by dora.

DoraArray is the counterpart to IntoArrow: dora node APIs hand received outputs to nodes as DoraArray, which is read back into plain Rust values through its TryFrom<&DoraArray> implementations.

The wrapped Arrow array is private. That is the whole point of the type: it is what lets dora change its internal Arrow major without breaking the 1.x contract. To reach the Arrow array itself, enable the feature naming the major you want — see the crate-level docs.

Two conversion shapes are provided, with different length contracts:

• Scalar conversions (bool, the primitive integer/float types, String, &str, and the chrono date/time types) require the array to hold exactly one element and no nulls; any other length is an error.
• Slice / Vec conversions (&[T] and Vec<T> for the primitive types) accept any length but still reject any null values.

Example

use dora_arrow_convert::{DoraArray, IntoArrow};

// Scalar: a single-element array converts to the value.
let data: DoraArray = 42_u8.into_arrow();
let scalar: u8 = (&data).try_into()?;
assert_eq!(scalar, 42);

// Strings follow the same single-element rule.
let data = "hello".to_string().into_arrow();
let text: String = (&data).try_into()?;
assert_eq!(text, "hello");

// Vec: any length, collected into an owned `Vec`.
let data = vec![1_i32, 2, 3].into_arrow();
let values: Vec<i32> = (&data).try_into()?;
assert_eq!(values, vec![1, 2, 3]);

// A multi-element array cannot be read as a scalar.
let data = vec![1_i32, 2, 3].into_arrow();
let scalar: Result<i32, _> = (&data).try_into();
assert!(scalar.is_err());

Implementations

impl DoraArray

pub fn len(&self) -> usize

The number of elements in the payload.

pub fn is_empty(&self) -> bool

Whether the payload holds no elements.

pub fn null_count(&self) -> usize

The number of null elements in the payload.

pub fn type_name(&self) -> String

A human-readable name for the payload’s Arrow type, e.g. "UInt8" or "List(Field { name: \"item\", .. })".

Returned as a String rather than an arrow_schema::DataType so that the ungated surface stays free of Arrow types. Use it for logging and error messages; to actually inspect the type, take the array through a version-gated accessor.

Trait Implementations

impl Clone for DoraArray

fn clone(&self) -> DoraArray

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DoraArray

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl IntoArrow for DoraArray

fn into_arrow(self) -> DoraArray

Convert the data into a dora payload.