Struct SequentialChain 

pub struct SequentialChain { /* private fields */ }

Sequential Chain

Executes multiple chains sequentially, where the output of one chain can be used as the input of the next.

Implementations

impl SequentialChain

pub fn new() -> Self

Create an empty SequentialChain.

pub fn with_name(self, name: impl Into<String>) -> Self

Set name.

pub fn add_chain( self, chain: Arc<dyn BaseChain>, input_keys: Vec<&str>, output_keys: Vec<&str>, ) -> Self

Add a Chain.

Arguments

• chain - Chain to add
• input_keys - Input keys (from global input)
• output_keys - Output keys (to global result)

pub fn add_chain_with_mapping( self, chain: Arc<dyn BaseChain>, input_mapping: HashMap<String, String>, output_mapping: HashMap<String, String>, ) -> Self

Add a Chain with mapping.

Arguments

• chain - Chain to add
• input_mapping - Input mapping {chain_input_key: global_key}
• output_mapping - Output mapping {chain_output_key: global_key}

Trait Implementations

impl BaseChain for SequentialChain

fn invoke_with_config<'life0, 'async_trait>( &'life0 self, inputs: HashMap<String, Value>, config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<ChainResult, ChainError>> + Send + 'async_trait>>

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

Execute the Chain with config propagation.

Dispatches this chain’s on_chain_start/on_chain_end and threads config (and thus callbacks) into every sub-chain via invoke_with_config — previously sub-chains were called with plain invoke, dropping the config at the composition boundary.

fn stream<'life0, 'async_trait>( &'life0 self, inputs: HashMap<String, Value>, ) -> Pin<Box<dyn Future<Output = Result<ChainStream, ChainError>> + Send + 'async_trait>>

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

Stream execution for SequentialChain.

Runs all chains except the last via invoke (since their output feeds into subsequent chains). The last chain’s output is streamed token by token by delegating to its stream() method; its output_mapping names the global output keys that stream stands for (validated in Self::stream_steps so a broken mapping fails loudly, P2-3).

fn stream_with_config<'life0, 'async_trait>( &'life0 self, inputs: HashMap<String, Value>, config: Option<RunnableConfig>, ) -> Pin<Box<dyn Future<Output = Result<ChainStream, ChainError>> + Send + 'async_trait>>

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

Stream execute the Chain with config propagation.

Dispatches this chain’s on_chain_start/on_chain_end and threads config into every sub-chain (invoke for intermediate steps, stream for the last step).

fn input_keys(&self) -> Vec<&str>

Get input keys.

fn output_keys(&self) -> Vec<&str>

Get output keys.

fn invoke<'life0, 'async_trait>( &'life0 self, inputs: HashMap<String, Value>, ) -> Pin<Box<dyn Future<Output = Result<ChainResult, ChainError>> + Send + 'async_trait>>

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

Execute the Chain.

fn name(&self) -> &str

Get Chain name.

fn validate_inputs( &self, inputs: &HashMap<String, Value>, ) -> Result<(), ChainError>

Validate inputs.

impl Debug for SequentialChain

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

Formats the value using the given formatter.

impl Default for SequentialChain

fn default() -> Self

Returns the “default value” for a type.