Struct ReduceSpec 

pub struct ReduceSpec { /* private fields */ }

A reduce operation over already-sorted input.

Every input table must already be sorted by a column set that starts with reduce_by — SortSpec is how a table gets that way. When it is, this is the operation to reach for: a map-reduce over the same data would pay for a shuffle that has already been done.

use ytsaurus_client::ReduceSpec;

let spec = ReduceSpec::new("./wordcount reduce", ["//tmp/sorted"], ["//tmp/counts"], ["word"])
    .with_local_file("//tmp/wordcount");

Implementations

impl ReduceSpec

pub fn new<I, O, K>( command: impl Into<String>, inputs: I, outputs: O, reduce_by: K, ) -> Self

where I: IntoIterator, I::Item: Into<String>, O: IntoIterator, O::Item: Into<String>, K: IntoIterator, K::Item: Into<String>,

A reduce running command over inputs, grouped by reduce_by.

pub fn with_local_file(self, path: impl Into<String>) -> Self

Adds a Cypress file the job needs — normally the worker binary.

pub fn with_local_file_named( self, path: impl Into<String>, name: impl AsRef<str>, ) -> Self

Adds a Cypress file under a different name in the job’s sandbox.

See MapSpec::with_local_file_named for why the name matters.

pub fn with_memory_limit(self, bytes: i64) -> Self

Sets the reducer’s memory limit, in bytes.

pub fn with_formats(self, input: DataFormat, output: DataFormat) -> Self

Selects the reducer’s input and output data formats.

YSON selections apply to every table. A Skiff selection must contain one table schema per corresponding input or output table, in the same order. The default remains binary YSON.

A Skiff reducer receives its key switch as a $key_switch boolean column rather than as a YSON control record, so the input schema has to declare that column for ytsaurus-job’s SkiffJobReader to report it — enable_key_switch asks the cluster to deliver key switches, and the format decides how they arrive. A schema without the column leaves a grouping reducer seeing one group, exactly as Self::without_key_switch would.

pub fn with_skiff_formats(self, input: SkiffFormat, output: SkiffFormat) -> Self

Uses validated Skiff formats for the reducer’s input and output streams.

This compatibility convenience delegates to Self::with_formats.

pub fn with_env(self, key: impl Into<String>, value: impl Into<String>) -> Self

Sets an environment variable for the job, e.g. RUST_BACKTRACE.

pub fn with_sort_by<K>(self, columns: K) -> Self

where K: IntoIterator, K::Item: Into<String>,

Sets the columns the input is sorted by, when they differ from reduce_by.

reduce_by must be a prefix of them. Saying so asks the cluster to check the input really is sorted that way, and guarantees the order rows arrive in within a group.

pub fn with_job_count(self, count: i64) -> Self

Requests a specific job count.

pub fn with_input_table_index(self) -> Self

Asks for the input table index to be delivered with each row.

Reduce merges several sorted tables into one stream, so this is how a job tells which table a row came from.

pub fn without_key_switch(self) -> Self

Turns off key_switch delivery to the reducer.

pub fn skiff_table_mismatch(&self) -> Option<String>

Describes a Skiff format that does not match this spec’s table lists.

A reduce merges its input tables into one sorted stream but keeps them distinguishable, so the input format describes every input table, as the Go SDK’s setupSkiffInputFormat also requires. See MapSpec::skiff_table_mismatch for what an unchecked mismatch costs. Client::start_reduce checks this before sending the spec.

pub fn with_raw(self, key: impl Into<String>, value: YsonValue) -> Self

Sets any spec field this builder does not model.

pub fn to_yson(&self) -> YsonValue

Renders the spec.

Trait Implementations

impl Clone for ReduceSpec

fn clone(&self) -> ReduceSpec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ReduceSpec

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

Formats the value using the given formatter.