Struct TransformingSource 

pub struct TransformingSource { /* private fields */ }

Source decorator that applies a fixed list of compiled stages to every record. Emits faucet_transform_* metrics per page via instrumented_apply_stages.

Example

use faucet_core::{RecordTransform, Source, TransformingSource};
use faucet_core::observability::Labels;
use faucet_core::stage::TransformStage;
use faucet_core::transform::KeyCaseMode;

let inner: Box<dyn Source> = build_inner();
let wrapped = TransformingSource::new(
    inner,
    vec![TransformStage::Map(RecordTransform::KeysCase { mode: KeyCaseMode::Snake })],
    Labels::for_named("rest"),
).unwrap();

Implementations

impl TransformingSource

pub fn new( inner: Box<dyn Source>, stages: Vec<TransformStage>, labels: Labels, ) -> Result<TransformingSource, FaucetError>

Compile stages and wrap inner. Returns FaucetError::Transform if any stage’s compilation fails (e.g. invalid regex in RenameKeys).

Trait Implementations

impl Source for TransformingSource

fn fetch_with_context<'life0, 'life1, 'async_trait>( &'life0 self, ctx: &'life1 HashMap<String, Value>, ) -> Pin<Box<dyn Future<Output = Result<Vec<Value>, FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, TransformingSource: 'async_trait,

Primary fetch method. Receives context from a parent source’s records.

fn fetch_with_context_incremental<'life0, 'life1, 'async_trait>( &'life0 self, ctx: &'life1 HashMap<String, Value>, ) -> Pin<Box<dyn Future<Output = Result<(Vec<Value>, Option<Value>), FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, TransformingSource: 'async_trait,

Incremental fetch with parent context support.

fn stream_pages<'a>( &'a self, ctx: &'a HashMap<String, Value>, batch_size: usize, ) -> Pin<Box<dyn Stream<Item = Result<StreamPage, FaucetError>> + Send + 'a>>

Stream records page-by-page so the pipeline can write to the sink as pages arrive instead of buffering the full result set.

fn state_key(&self) -> Option<String>

Stable key under which this source’s incremental-replication bookmark should be persisted in a StateStore.

fn apply_start_bookmark<'life0, 'async_trait>( &'life0 self, bookmark: Value, ) -> Pin<Box<dyn Future<Output = Result<(), FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, TransformingSource: 'async_trait,

Apply a bookmark loaded from a StateStore as this run’s starting point.

fn connector_name(&self) -> &'static str

Stable identifier used as the connector label on metrics and the connector attribute on spans. Defaults to the final segment of std::any::type_name::<Self>(), e.g. "RestSource". Built-in connectors override with a short, friendly snake_case name (e.g. "rest"). Must return a non-empty string; observability decorators fall back to "unknown" in release builds if it is empty (and debug_assert! in debug builds).

fn fetch_all<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Vec<Value>, FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: 'async_trait,

Convenience: fetch with no parent context.

fn fetch_all_incremental<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<(Vec<Value>, Option<Value>), FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: 'async_trait,

Convenience: incremental fetch with no parent context.

fn config_schema(&self) -> Value

Return a JSON Schema describing the configuration this source accepts.

fn check<'life0, 'life1, 'async_trait>( &'life0 self, ctx: &'life1 CheckContext, ) -> Pin<Box<dyn Future<Output = Result<CheckReport, FaucetError>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Run a fast, non-mutating preflight probe (used by faucet doctor).