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如何拆分JSON数据

此 JSON 分割器 分割 JSON 数据,同时允许控制块大小。它以深度优先的方式遍历 JSON 数据,并构建较小的 JSON 块。它会尝试保持嵌套的 JSON 对象完整,但如果需要,也会将其拆分,以确保块大小介于最小块大小和最大块大小之间。

如果该值不是嵌套的 JSON,而是一个非常长的字符串,则不会对其进行拆分。如果您需要对块大小进行硬性限制,可以考虑在这些块上使用递归文本拆分器进行组合。可选的预处理步骤是将列表拆分,方法是先将其转换为 JSON(字典),然后再按此方式拆分。

  1. 文本分割方式:json值。
  2. 块大小的度量方式:按字符数量计算。
%pip install -qU langchain-text-splitters

首先,我们加载一些JSON数据:

import json

import requests

# This is a large nested json object and will be loaded as a python dict
json_data = requests.get("https://api.smith.langchain.com/openapi.json").json()

基本用法

指定 max_chunk_size 以限制块大小:

from langchain_text_splitters import RecursiveJsonSplitter

splitter = RecursiveJsonSplitter(max_chunk_size=300)

要获取 JSON 块,请使用 .split_json 方法:

# Recursively split json data - If you need to access/manipulate the smaller json chunks
json_chunks = splitter.split_json(json_data=json_data)

for chunk in json_chunks[:3]:
print(chunk)
{'openapi': '3.1.0', 'info': {'title': 'LangSmith', 'version': '0.1.0'}, 'servers': [{'url': 'https://api.smith.langchain.com', 'description': 'LangSmith API endpoint.'}]}
{'paths': {'/api/v1/sessions/{session_id}': {'get': {'tags': ['tracer-sessions'], 'summary': 'Read Tracer Session', 'description': 'Get a specific session.', 'operationId': 'read_tracer_session_api_v1_sessions__session_id__get'}}}}
{'paths': {'/api/v1/sessions/{session_id}': {'get': {'security': [{'API Key': []}, {'Tenant ID': []}, {'Bearer Auth': []}]}}}}

要获取 LangChain 文档 对象,请使用 .create_documents 方法:

# The splitter can also output documents
docs = splitter.create_documents(texts=[json_data])

for doc in docs[:3]:
print(doc)
page_content='{"openapi": "3.1.0", "info": {"title": "LangSmith", "version": "0.1.0"}, "servers": [{"url": "https://api.smith.langchain.com", "description": "LangSmith API endpoint."}]}'
page_content='{"paths": {"/api/v1/sessions/{session_id}": {"get": {"tags": ["tracer-sessions"], "summary": "Read Tracer Session", "description": "Get a specific session.", "operationId": "read_tracer_session_api_v1_sessions__session_id__get"}}}}'
page_content='{"paths": {"/api/v1/sessions/{session_id}": {"get": {"security": [{"API Key": []}, {"Tenant ID": []}, {"Bearer Auth": []}]}}}}'

或者使用 .split_text 直接获取字符串内容:

texts = splitter.split_text(json_data=json_data)

print(texts[0])
print(texts[1])
{"openapi": "3.1.0", "info": {"title": "LangSmith", "version": "0.1.0"}, "servers": [{"url": "https://api.smith.langchain.com", "description": "LangSmith API endpoint."}]}
{"paths": {"/api/v1/sessions/{session_id}": {"get": {"tags": ["tracer-sessions"], "summary": "Read Tracer Session", "description": "Get a specific session.", "operationId": "read_tracer_session_api_v1_sessions__session_id__get"}}}}

如何管理列表内容的块大小

请注意,此示例中的一个块的大小超过了指定的 300 的 max_chunk_size。查看其中一个较大的块,我们发现其中包含一个列表对象:

print([len(text) for text in texts][:10])
print()
print(texts[3])
[171, 231, 126, 469, 210, 213, 237, 271, 191, 232]

{"paths": {"/api/v1/sessions/{session_id}": {"get": {"parameters": [{"name": "session_id", "in": "path", "required": true, "schema": {"type": "string", "format": "uuid", "title": "Session Id"}}, {"name": "include_stats", "in": "query", "required": false, "schema": {"type": "boolean", "default": false, "title": "Include Stats"}}, {"name": "accept", "in": "header", "required": false, "schema": {"anyOf": [{"type": "string"}, {"type": "null"}], "title": "Accept"}}]}}}}

默认情况下,JSON 分割器不会拆分列表。

指定 convert_lists=True 以预处理 JSON,将列表内容转换为以 index:item 作为 key:val 的键值对:

texts = splitter.split_text(json_data=json_data, convert_lists=True)

让我们看看分块的大小。现在它们都小于最大值

print([len(text) for text in texts][:10])
[176, 236, 141, 203, 212, 221, 210, 213, 242, 291]

列表已转换为字典,即使被拆分为多个片段,仍保留所有必要的上下文信息:

print(texts[1])
{"paths": {"/api/v1/sessions/{session_id}": {"get": {"tags": {"0": "tracer-sessions"}, "summary": "Read Tracer Session", "description": "Get a specific session.", "operationId": "read_tracer_session_api_v1_sessions__session_id__get"}}}}
# We can also look at the documents
docs[1]
Document(page_content='{"paths": {"/api/v1/sessions/{session_id}": {"get": {"tags": ["tracer-sessions"], "summary": "Read Tracer Session", "description": "Get a specific session.", "operationId": "read_tracer_session_api_v1_sessions__session_id__get"}}}}')