Adding Callbacks in Text Splitters for instrumentation

[punitmahes]

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Feature request

Currently, LangChain’s text splitters operate in isolation and lack support for callback handlers. Introducing callback handlers to text splitters can provide significant benefits, such as real-time monitoring, debugging, and custom instrumentation of the text-splitting process.

Motivation

Currently, LangChain’s text splitters don’t provide a way to track or debug the splitting process. Adding callback handlers would let users monitor key details like chunk size, chunk overlap, and the total number of chunks. This would help in debugging, performance analysis, and adding custom logic during the splitting process, while keeping the behavior consistent with other parts of LangChain that support callbacks.

Proposal (If applicable)

No response