Class LogStreamCallbackHandler

Class that extends the BaseTracer class from the langchain.callbacks.tracers.base module. It represents a callback handler that logs the execution of runs and emits RunLog instances to a RunLogStream.

Hierarchy

BaseTracer
- LogStreamCallbackHandler

Index

Constructors

constructor

Properties

awaitHandlers ignoreAgent ignoreChain ignoreLLM ignoreRetriever name receiveStream writer autoClose runMap transformStream excludeNames? excludeTags? excludeTypes? includeNames? includeTags? includeTypes? rootId?

Constructors

constructor

new LogStreamCallbackHandler(fields?): LogStreamCallbackHandler
Parameters
- Optional fields: LogStreamCallbackHandlerInput
Returns LogStreamCallbackHandler
Overrides BaseTracer.constructor
- Defined in langchain-core/src/tracers/log_stream.ts:322

Properties

awaitHandlers

awaitHandlers: boolean = ...

ignoreAgent

ignoreAgent: boolean = false

ignoreChain

ignoreChain: boolean = false

ignoreLLM

ignoreLLM: boolean = false

ignoreRetriever

ignoreRetriever: boolean = false

name

name: string = "log_stream_tracer"

receiveStream

receiveStream: IterableReadableStream<RunLogPatch>

writer

writer: WritableStreamDefaultWriter<any>

`Protected` autoClose

autoClose: boolean = true

`Protected` runMap

runMap: Map<string, Run> = ...

`Protected` transformStream

transformStream: TransformStream<any, any>

`Protected` `Optional` excludeNames

excludeNames?: string[]

`Protected` `Optional` excludeTags

excludeTags?: string[]

`Protected` `Optional` excludeTypes

excludeTypes?: string[]

`Protected` `Optional` includeNames

includeNames?: string[]

`Protected` `Optional` includeTags

includeTags?: string[]

`Protected` `Optional` includeTypes

includeTypes?: string[]

`Protected` `Optional` rootId

rootId?: string

Methods

[asyncIterator]

[asyncIterator](): IterableReadableStream<RunLogPatch>
Returns IterableReadableStream<RunLogPatch>
- Defined in langchain-core/src/tracers/log_stream.ts:339

copy

copy(): LogStreamCallbackHandler
Returns LogStreamCallbackHandler
Inherited from BaseTracer.copy
- Defined in langchain-core/src/tracers/base.ts:64

handleAgentAction

handleAgentAction(action, runId): Promise<void>
Called when an agent is about to execute an action, with the action and the run ID.
Parameters
- action: AgentAction
- runId: string
Returns Promise<void>
Inherited from BaseTracer.handleAgentAction
- Defined in langchain-core/src/tracers/base.ts:420

handleAgentEnd

handleAgentEnd(action, runId): Promise<void>
Called when an agent finishes execution, before it exits. with the final output and the run ID.
Parameters
- action: AgentFinish
- runId: string
Returns Promise<void>
Inherited from BaseTracer.handleAgentEnd
- Defined in langchain-core/src/tracers/base.ts:436

handleChainEnd

handleChainEnd(outputs, runId, _parentRunId?, _tags?, kwargs?): Promise<Run>
Called at the end of a Chain run, with the outputs and the run ID.
Parameters
- outputs: ChainValues
- runId: string
- Optional _parentRunId: string
- Optional _tags: string[]
- Optional kwargs: {
  inputs?: Record<string, unknown>;
  }
  - Optional inputs?: Record<string, unknown>
Returns Promise<Run>
Inherited from BaseTracer.handleChainEnd
- Defined in langchain-core/src/tracers/base.ts:301

handleChainError

handleChainError(error, runId, _parentRunId?, _tags?, kwargs?): Promise<Run>
Called if a Chain run encounters an error
Parameters
- error: unknown
- runId: string
- Optional _parentRunId: string
- Optional _tags: string[]
- Optional kwargs: {
  inputs?: Record<string, unknown>;
  }
  - Optional inputs?: Record<string, unknown>
Returns Promise<Run>
Inherited from BaseTracer.handleChainError
- Defined in langchain-core/src/tracers/base.ts:326

handleChainStart

handleChainStart(chain, inputs, runId, parentRunId?, tags?, metadata?, runType?, name?): Promise<Run>
Called at the start of a Chain run, with the chain name and inputs and the run ID.
Parameters
- chain: Serialized
- inputs: ChainValues
- runId: string
- Optional parentRunId: string
- Optional tags: string[]
- Optional metadata: KVMap
- Optional runType: string
- Optional name: string
Returns Promise<Run>
Inherited from BaseTracer.handleChainStart
- Defined in langchain-core/src/tracers/base.ts:264

handleChatModelStart

handleChatModelStart(llm, messages, runId, parentRunId?, extraParams?, tags?, metadata?, name?): Promise<Run>
Called at the start of a Chat Model run, with the prompt(s) and the run ID.
Parameters
- llm: Serialized
- messages: BaseMessage[][]
- runId: string
- Optional parentRunId: string
- Optional extraParams: KVMap
- Optional tags: string[]
- Optional metadata: KVMap
- Optional name: string
Returns Promise<Run>
Inherited from BaseTracer.handleChatModelStart
- Defined in langchain-core/src/tracers/base.ts:191

handleLLMEnd

handleLLMEnd(output, runId): Promise<Run>
Called at the end of an LLM/ChatModel run, with the output and the run ID.
Parameters
- output: LLMResult
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleLLMEnd
- Defined in langchain-core/src/tracers/base.ts:232

handleLLMError

handleLLMError(error, runId): Promise<Run>
Called if an LLM/ChatModel run encounters an error
Parameters
- error: unknown
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleLLMError
- Defined in langchain-core/src/tracers/base.ts:248

handleLLMNewToken

handleLLMNewToken(token, idx, runId, _parentRunId?, _tags?, fields?): Promise<Run>
Called when an LLM/ChatModel in streaming mode produces a new token
Parameters
- token: string
- idx: NewTokenIndices
  
  idx.prompt is the index of the prompt that produced the token (if there are multiple prompts) idx.completion is the index of the completion that produced the token (if multiple completions per prompt are requested)
- runId: string
- Optional _parentRunId: string
- Optional _tags: string[]
- Optional fields: HandleLLMNewTokenCallbackFields
Returns Promise<Run>
Inherited from BaseTracer.handleLLMNewToken
- Defined in langchain-core/src/tracers/base.ts:534

handleLLMStart

handleLLMStart(llm, prompts, runId, parentRunId?, extraParams?, tags?, metadata?, name?): Promise<Run>
Called at the start of an LLM or Chat Model run, with the prompt(s) and the run ID.
Parameters
- llm: Serialized
- prompts: string[]
- runId: string
- Optional parentRunId: string
- Optional extraParams: KVMap
- Optional tags: string[]
- Optional metadata: KVMap
- Optional name: string
Returns Promise<Run>
Inherited from BaseTracer.handleLLMStart
- Defined in langchain-core/src/tracers/base.ts:150

handleRetrieverEnd

handleRetrieverEnd(documents, runId): Promise<Run>
Parameters
- documents: Document<Record<string, unknown>>[]
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleRetrieverEnd
- Defined in langchain-core/src/tracers/base.ts:486

handleRetrieverError

handleRetrieverError(error, runId): Promise<Run>
Parameters
- error: unknown
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleRetrieverError
- Defined in langchain-core/src/tracers/base.ts:505

handleRetrieverStart

handleRetrieverStart(retriever, query, runId, parentRunId?, tags?, metadata?, name?): Promise<Run>
Parameters
- retriever: Serialized
- query: string
- runId: string
- Optional parentRunId: string
- Optional tags: string[]
- Optional metadata: KVMap
- Optional name: string
Returns Promise<Run>
Inherited from BaseTracer.handleRetrieverStart
- Defined in langchain-core/src/tracers/base.ts:449

handleText

handleText(text, runId): Promise<void>
Parameters
- text: string
- runId: string
Returns Promise<void>
Inherited from BaseTracer.handleText
- Defined in langchain-core/src/tracers/base.ts:521

handleToolEnd

handleToolEnd(output, runId): Promise<Run>
Called at the end of a Tool run, with the tool output and the run ID.
Parameters
- output: string
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleToolEnd
- Defined in langchain-core/src/tracers/base.ts:388

handleToolError

handleToolError(error, runId): Promise<Run>
Called if a Tool run encounters an error
Parameters
- error: unknown
- runId: string
Returns Promise<Run>
Inherited from BaseTracer.handleToolError
- Defined in langchain-core/src/tracers/base.ts:404

handleToolStart

handleToolStart(tool, input, runId, parentRunId?, tags?, metadata?, name?): Promise<Run>
Called at the start of a Tool run, with the tool name and input and the run ID.
Parameters
- tool: Serialized
- input: string
- runId: string
- Optional parentRunId: string
- Optional tags: string[]
- Optional metadata: KVMap
- Optional name: string
Returns Promise<Run>
Inherited from BaseTracer.handleToolStart
- Defined in langchain-core/src/tracers/base.ts:351

onLLMNewToken

onLLMNewToken(run, token, kwargs?): Promise<void>
Parameters
- run: Run
- token: string
- Optional kwargs: HandleLLMNewTokenCallbackFields
Returns Promise<void>
Overrides BaseTracer.onLLMNewToken
- Defined in langchain-core/src/tracers/log_stream.ts:522

onRunCreate

onRunCreate(run): Promise<void>
Parameters
- run: Run
Returns Promise<void>
Overrides BaseTracer.onRunCreate
- Defined in langchain-core/src/tracers/log_stream.ts:410

onRunUpdate

onRunUpdate(run): Promise<void>
Parameters
- run: Run
Returns Promise<void>
Overrides BaseTracer.onRunUpdate
- Defined in langchain-core/src/tracers/log_stream.ts:475

tapOutputIterable

tapOutputIterable<T>(runId, output): AsyncGenerator<T, any, unknown>
Type Parameters
- T
Parameters
- runId: string
- output: AsyncGenerator<T, any, unknown>
Returns AsyncGenerator<T, any, unknown>
- Defined in langchain-core/src/tracers/log_stream.ts:381

toJSON

toJSON(): Serialized
Returns Serialized
Inherited from BaseTracer.toJSON
- Defined in langchain-core/src/callbacks/base.ts:355

toJSONNotImplemented

toJSONNotImplemented(): SerializedNotImplemented
Returns SerializedNotImplemented
Inherited from BaseTracer.toJSONNotImplemented
- Defined in langchain-core/src/callbacks/base.ts:359

`Optional` onAgentAction

onAgentAction(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onAgentAction
- Defined in langchain-core/src/tracers/base.ts:581

`Optional` onAgentEnd

onAgentEnd(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onAgentEnd
- Defined in langchain-core/src/tracers/base.ts:583

`Optional` onChainEnd

onChainEnd(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onChainEnd
- Defined in langchain-core/src/tracers/base.ts:571

`Optional` onChainError

onChainError(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onChainError
- Defined in langchain-core/src/tracers/base.ts:573

`Optional` onChainStart

onChainStart(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onChainStart
- Defined in langchain-core/src/tracers/base.ts:569

`Optional` onLLMEnd

onLLMEnd(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onLLMEnd
- Defined in langchain-core/src/tracers/base.ts:565

`Optional` onLLMError

onLLMError(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onLLMError
- Defined in langchain-core/src/tracers/base.ts:567

`Optional` onLLMStart

onLLMStart(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onLLMStart
- Defined in langchain-core/src/tracers/base.ts:563

`Optional` onRetrieverEnd

onRetrieverEnd(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onRetrieverEnd
- Defined in langchain-core/src/tracers/base.ts:587

`Optional` onRetrieverError

onRetrieverError(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onRetrieverError
- Defined in langchain-core/src/tracers/base.ts:589

`Optional` onRetrieverStart

onRetrieverStart(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onRetrieverStart
- Defined in langchain-core/src/tracers/base.ts:585

`Optional` onText

onText(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onText
- Defined in langchain-core/src/tracers/base.ts:591

`Optional` onToolEnd

onToolEnd(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onToolEnd
- Defined in langchain-core/src/tracers/base.ts:577

`Optional` onToolError

onToolError(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onToolError
- Defined in langchain-core/src/tracers/base.ts:579

`Optional` onToolStart

onToolStart(run): void | Promise<void>
Parameters
- run: Run
Returns void | Promise<void>
Inherited from BaseTracer.onToolStart
- Defined in langchain-core/src/tracers/base.ts:575

`Static` fromMethods

fromMethods(methods): Handler
Parameters
- methods: BaseCallbackHandlerMethodsClass
Returns Handler
Inherited from BaseTracer.fromMethods
- Defined in langchain-core/src/callbacks/base.ts:363

`Protected` persistRun

persistRun(_run): Promise<void>
Parameters
- _run: Run
Returns Promise<void>
Overrides BaseTracer.persistRun
- Defined in langchain-core/src/tracers/log_stream.ts:343

`Protected` stringifyError

stringifyError(error): string
Parameters
- error: unknown
Returns string
Inherited from BaseTracer.stringifyError
- Defined in langchain-core/src/tracers/base.ts:68

Class LogStreamCallbackHandler

Hierarchy

Index

Constructors

Properties

Methods

Constructors

constructor

Parameters

Optional fields: LogStreamCallbackHandlerInput

Returns LogStreamCallbackHandler

Properties

awaitHandlers

ignoreAgent

ignoreChain

ignoreLLM

ignoreRetriever

name

receiveStream

writer

Protected autoClose

Protected runMap

Protected transformStream

Protected Optional excludeNames

Protected Optional excludeTags

Protected Optional excludeTypes

Protected Optional includeNames

Protected Optional includeTags

Protected Optional includeTypes

Protected Optional rootId

Methods

[asyncIterator]

Returns IterableReadableStream<RunLogPatch>

copy

Returns LogStreamCallbackHandler

handleAgentAction

Parameters

action: AgentAction

runId: string

Returns Promise<void>

handleAgentEnd

Parameters

action: AgentFinish

runId: string

Returns Promise<void>

handleChainEnd

Parameters

outputs: ChainValues

runId: string

Optional _parentRunId: string

Optional _tags: string[]

Optional kwargs: { inputs?: Record<string, unknown>; }

Optional inputs?: Record<string, unknown>

Returns Promise<Run>

handleChainError

Parameters

error: unknown

runId: string

Optional _parentRunId: string

Optional _tags: string[]

Optional kwargs: { inputs?: Record<string, unknown>; }

Optional inputs?: Record<string, unknown>

Returns Promise<Run>

handleChainStart

Parameters

chain: Serialized

inputs: ChainValues

runId: string

Optional parentRunId: string

Optional tags: string[]

Optional metadata: KVMap

Optional runType: string

Optional name: string

Returns Promise<Run>

handleChatModelStart

Parameters

llm: Serialized

messages: BaseMessage[][]

runId: string

Optional parentRunId: string

`Optional` fields: LogStreamCallbackHandlerInput

`Protected` autoClose

`Protected` runMap

`Protected` transformStream

`Protected` `Optional` excludeNames

`Protected` `Optional` excludeTags

`Protected` `Optional` excludeTypes

`Protected` `Optional` includeNames

`Protected` `Optional` includeTags

`Protected` `Optional` includeTypes

`Protected` `Optional` rootId

`Optional` _parentRunId: string

`Optional` _tags: string[]

`Optional` kwargs: {
inputs?: Record<string, unknown>;
}

`Optional` inputs?: Record<string, unknown>

`Optional` _parentRunId: string

`Optional` _tags: string[]

`Optional` kwargs: {
inputs?: Record<string, unknown>;
}

`Optional` inputs?: Record<string, unknown>

`Optional` parentRunId: string

`Optional` tags: string[]

`Optional` metadata: KVMap

`Optional` runType: string

`Optional` name: string

`Optional` parentRunId: string

`Optional` extraParams: KVMap

`Optional` tags: string[]

`Optional` metadata: KVMap

`Optional` name: string

`Optional` _parentRunId: string

`Optional` _tags: string[]

`Optional` fields: HandleLLMNewTokenCallbackFields

`Optional` parentRunId: string

`Optional` extraParams: KVMap

`Optional` tags: string[]

`Optional` metadata: KVMap

`Optional` name: string

`Optional` parentRunId: string

`Optional` tags: string[]

`Optional` metadata: KVMap

`Optional` name: string