langchain_core.runnables.schema
.StreamEvent¶
- class langchain_core.runnables.schema.StreamEvent[source]¶
流式事件。
从astream_events方法产生的流式事件的模式。
示例:
from langchain_core.runnables import RunnableLambda async def reverse(s: str) -> str: return s[::-1] chain = RunnableLambda(func=reverse) events = [event async for event in chain.astream_events("hello")] # 将产生以下事件(为简洁起见,省略了run_id): [ { "data": {"input": "hello"}, "event": "on_chain_start", "metadata": {}, "name": "reverse", "tags": [], }, { "data": {"chunk": "olleh"}, "event": "on_chain_stream", "metadata": {}, "name": "reverse", "tags": [], }, { "data": {"output": "olleh"}, "event": "on_chain_end", "metadata": {}, "name": "reverse", "tags": [], }, ]
Attributes
event
事件名称的格式为:on_[runnable_type]_(start|stream|end)。
name
生成事件的可运行对象的名称。
run_id
一个随机生成的ID,用于跟踪给定可运行对象的执行情况。
tags
与生成此事件的可运行程序相关联的标签。
metadata
与生成此事件的可运行程序相关的元数据。
data
事件数据。
Methods
__init__
(*args, **kwargs)clear
()copy
()fromkeys
([value])Create a new dictionary with keys from iterable and values set to value.
get
(key[, default])Return the value for key if key is in the dictionary, else default.
items
()keys
()pop
(k[,d])If the key is not found, return the default if given; otherwise, raise a KeyError.
popitem
()Remove and return a (key, value) pair as a 2-tuple.
setdefault
(key[, default])Insert key with a value of default if key is not in the dictionary.
update
([E, ]**F)If E is present and has a .keys() method, then does: for k in E: D[k] = E[k] If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k]
values
()- __init__(*args, **kwargs)¶
- clear() None. Remove all items from D. ¶
- copy() a shallow copy of D ¶
- fromkeys(value=None, /)¶
Create a new dictionary with keys from iterable and values set to value.
- get(key, default=None, /)¶
Return the value for key if key is in the dictionary, else default.
- items() a set-like object providing a view on D's items ¶
- keys() a set-like object providing a view on D's keys ¶
- pop(k[, d]) v, remove specified key and return the corresponding value. ¶
If the key is not found, return the default if given; otherwise, raise a KeyError.
- popitem()¶
Remove and return a (key, value) pair as a 2-tuple.
Pairs are returned in LIFO (last-in, first-out) order. Raises KeyError if the dict is empty.
- setdefault(key, default=None, /)¶
Insert key with a value of default if key is not in the dictionary.
Return the value for key if key is in the dictionary, else default.
- update([E, ]**F) None. Update D from dict/iterable E and F. ¶
If E is present and has a .keys() method, then does: for k in E: D[k] = E[k] If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k]
- values() an object providing a view on D's values ¶