Struct Context 

pub struct Context<'a> { /* private fields */ }

The runtime handle passed to Operation::execute.

A Context is a per-step view of the pipeline: it borrows the operation’s OperationMetadata, the runtime Store, the registered Extensions, and a scoped prefix for looking up parameters. Operations use it to read declared inputs, fetch extensions, emit errors, and record outputs. Outputs are staged in two internal stores (operation-scoped and global) and merged back into the runtime store after the step finishes.

A Context validates every access against its metadata — calling input, set_static_output, set_derived_output, or extension with a name the operation did not declare returns an OperationError rather than silently succeeding.

Implementations

impl Context<'_>

pub fn new<'a>( metadata: OperationMetadata, param_prefix: &'a str, store: &'a Store<StoreEntry>, extensions: &'a Extensions, ) -> Context<'a>

Constructs a fresh Context with empty staged-output stores. Called by the runtime immediately before a step executes; not typically invoked from operation code.

pub fn input(&self, name: &str) -> Result<&StoreEntry, OperationError>

Looks up a declared input by name, applying the step’s parameter prefix automatically. Fails with OperationError::UndeclaredInput if the name is not in the operation’s metadata.

pub fn set_static_output( &mut self, name: &'static str, entry: impl Into<StoreEntry>, ) -> Result<(), OperationError>

Records a statically-named output declared on the operation’s metadata as NameSpec::Static. Fails with OperationError::UndeclaredOutput if no matching output is declared.

pub fn set_derived_output( &mut self, input_name: &str, entry: impl Into<StoreEntry>, ) -> Result<(), OperationError>

Records an output whose name is derived from a text input, declared on the operation’s metadata as NameSpec::DerivedFrom or NameSpec::DerivedWithDefault. Fails with OperationError::UndeclaredDerivedOutput if no matching output is declared.

pub fn extension<T: Extension>( &self, spec_name: &str, ) -> Result<&T, OperationError>

Looks up a registered Extension of type T under a declared extension spec. Fails with OperationError::ExtensionNotFound if the spec is undeclared or no extension was registered under the resolved name.

pub fn error(&self, message: impl Into<String>) -> OperationError

Builds an OperationError::Custom tagged with the operation’s name for ad-hoc failure reporting. Prefer the op_error! macro for format!-style construction.