Files
yiliao/backend/services/llm_service.py

507 lines
22 KiB
Python
Raw Normal View History

import os
import json
from typing import Dict, Any, List
class LLMService:
"""大语言模型服务支持本地Ollama或OpenAI API"""
def __init__(self):
self.llm_type = self._detect_llm_type()
self._initialize_llm()
def _detect_llm_type(self) -> str:
"""检测可用的LLM类型"""
# 优先使用 DeepSeek如果已配置
if os.getenv("DEEPSEEK_API_KEY") and os.getenv("USE_DEEPSEEK_LLM", "true").lower() == "true":
return "deepseek"
# 检查 OpenAI
elif os.getenv("OPENAI_API_KEY"):
return "openai"
# Coze如果已配置
elif os.getenv("COZE_API_KEY") and os.getenv("COZE_WORKFLOW_ID"):
return "coze"
elif os.getenv("OLLAMA_HOST") or self._check_ollama_available():
return "ollama"
else:
return "mock"
def _check_ollama_available(self) -> bool:
"""检查Ollama是否可用"""
try:
import requests
response = requests.get("http://localhost:11434/api/tags", timeout=2)
return response.status_code == 200
except:
return False
def _initialize_llm(self):
"""初始化LLM客户端"""
if self.llm_type == "deepseek":
try:
self.deepseek_api_key = os.getenv("DEEPSEEK_API_KEY")
self.deepseek_api_url = os.getenv("DEEPSEEK_API_BASE", "https://api.deepseek.com") + "/v1/chat/completions"
self.model = os.getenv("DEEPSEEK_MODEL", "deepseek-chat")
print(f"✓ 使用 DeepSeek API (模型: {self.model})")
except Exception as e:
print(f"⚠ DeepSeek 初始化失败: {e}")
self.llm_type = "mock"
elif self.llm_type == "openai":
try:
from openai import OpenAI
# 支持自定义API端点
api_key = os.getenv("OPENAI_API_KEY")
api_base = os.getenv("OPENAI_API_BASE")
if api_base:
self.client = OpenAI(api_key=api_key, base_url=api_base)
else:
self.client = OpenAI(api_key=api_key)
self.model = os.getenv("OPENAI_MODEL", "gpt-3.5-turbo")
print(f"✓ 使用 OpenAI API (模型: {self.model})")
except Exception as e:
print(f"⚠ OpenAI 初始化失败: {e}")
self.llm_type = "mock"
elif self.llm_type == "ollama":
try:
import requests
self.ollama_host = os.getenv("OLLAMA_HOST", "http://localhost:11434")
# 默认使用已安装的 qwen2.5:7b 模型,如需更换可通过 OLLAMA_MODEL 环境变量覆盖
self.model = os.getenv("OLLAMA_MODEL", "qwen2.5:7b")
print(f"✓ 使用 Ollama (模型: {self.model})")
except Exception as e:
print(f"⚠ Ollama 初始化失败: {e}")
self.llm_type = "mock"
elif self.llm_type == "coze":
try:
# Coze 工作流调用所需配置,通过环境变量提供
self.coze_api_url = os.getenv("COZE_API_URL", "https://api.coze.cn/v1/workflow/run")
self.coze_api_key = os.getenv("COZE_API_KEY")
self.coze_workflow_id = os.getenv("COZE_WORKFLOW_ID")
if not self.coze_api_key or not self.coze_workflow_id:
raise ValueError("COZE_API_KEY 或 COZE_WORKFLOW_ID 未配置")
print("✓ 使用 Coze 工作流作为LLM")
except Exception as e:
print(f"⚠ Coze 初始化失败: {e}")
self.llm_type = "mock"
if self.llm_type == "mock":
print("✓ 使用模拟LLM模式用于演示")
def analyze_single_report(self, report_text: str) -> Dict[str, Any]:
"""分析单个报告"""
prompt = f"""请分析以下医疗报告,提取关键信息:
{report_text}
请提供
1. 摘要
2. 关键发现
3. 异常指标
4. 风险评估
5. 建议
以JSON格式返回结果
"""
if self.llm_type == "deepseek":
return self._call_deepseek(prompt)
elif self.llm_type == "openai":
return self._call_openai(prompt)
elif self.llm_type == "ollama":
return self._call_ollama(prompt)
elif self.llm_type == "coze":
# 对于 Coze直接将原始报告文本传给工作流由工作流内部负责解析与生成结构化结果
print(f" → 准备调用 Coze 工作流...")
coze_input = [{
"filename": "single_report",
"text": report_text,
}]
result = self._call_coze(coze_input) # 单个报告也作为数组传入
print(f" ← Coze 调用返回")
return result
else:
return self._mock_analysis(report_text)
def analyze_multiple_reports(self, report_texts: List[str]) -> Dict[str, Any]:
"""
分析多个报告Coze专用
report_texts: 报告文本的数组每个元素是一个PDF的文本
"""
if self.llm_type == "coze":
print(f" → 准备调用 Coze 工作流(传入 {len(report_texts)} 个报告)...")
result = self._call_coze(report_texts)
print(f" ← Coze 调用返回")
return result
else:
# 其他LLM类型合并文本后调用
combined = "\n\n".join(report_texts)
return self.analyze_single_report(combined)
def _call_openai(self, prompt: str) -> Dict[str, Any]:
"""调用OpenAI API"""
try:
response = self.client.chat.completions.create(
model=self.model,
messages=[
{"role": "system", "content": "你是一位专业的医疗报告分析助手。"},
{"role": "user", "content": prompt}
],
temperature=0.7,
max_tokens=2000
)
content = response.choices[0].message.content
return self._parse_llm_response(content)
except Exception as e:
return {
"error": f"OpenAI API 调用失败: {str(e)}",
"summary": "分析失败",
"key_findings": [],
"abnormal_items": [],
"risk_assessment": "无法评估",
"recommendations": []
}
def _call_deepseek(self, prompt: str) -> Dict[str, Any]:
"""调用 DeepSeek API"""
try:
import requests
headers = {
"Authorization": f"Bearer {self.deepseek_api_key}",
"Content-Type": "application/json"
}
data = {
"model": self.model,
"messages": [
{"role": "system", "content": "你是一位专业的医疗报告分析助手。请以JSON格式返回分析结果。"},
{"role": "user", "content": prompt}
],
"temperature": 0.3,
"max_tokens": 4000
}
response = requests.post(
self.deepseek_api_url,
headers=headers,
json=data,
timeout=120
)
if response.status_code == 200:
content = response.json()["choices"][0]["message"]["content"]
return self._parse_llm_response(content)
else:
raise Exception(f"DeepSeek 返回错误: {response.status_code} - {response.text}")
except Exception as e:
return {
"error": f"DeepSeek API 调用失败: {str(e)}",
"summary": "分析失败",
"key_findings": [],
"abnormal_items": [],
"risk_assessment": "无法评估",
"recommendations": []
}
def _call_coze(self, report_texts: List[str]) -> Dict[str, Any]:
"""
调用 Coze 工作流 API流式模式对医疗报告进行分析
report_texts: 报告文本数组每个元素是一个PDF的文本
"""
try:
import time
from cozepy import Coze, TokenAuth, COZE_CN_BASE_URL, WorkflowEventType
api_key = getattr(self, "coze_api_key", os.getenv("COZE_API_KEY"))
workflow_id = getattr(self, "coze_workflow_id", os.getenv("COZE_WORKFLOW_ID"))
max_retries = int(os.getenv("COZE_MAX_RETRIES", "3"))
if not api_key or not workflow_id:
raise ValueError("未配置 Coze API 所需的 COZE_API_KEY 或 COZE_WORKFLOW_ID")
print(f" → 调用 Coze 工作流(流式模式)...")
print(f" → Workflow ID: {workflow_id}")
print(f" → 数组元素个数: {len(report_texts)}")
total_chars = 0
for item in report_texts:
if isinstance(item, str):
total_chars += len(item)
elif isinstance(item, dict):
text_value = item.get("text")
if isinstance(text_value, str):
total_chars += len(text_value)
print(f" → 总文本长度: {total_chars} 字符")
print(f" → 请求发送时间: {time.strftime('%H:%M:%S')}")
# 初始化 Coze 客户端
coze = Coze(auth=TokenAuth(token=api_key), base_url=COZE_CN_BASE_URL)
# 添加请求开始时间
import time as time_module
start = time_module.time()
last_error = None
for attempt in range(max_retries):
try:
if attempt > 0:
print(f" → 重试 {attempt}/{max_retries - 1}...")
# 调用流式接口
stream = coze.workflows.runs.stream(
workflow_id=workflow_id,
parameters={"input": report_texts}
)
print(f" ✓ 已连接到流式接口,等待执行...")
# 处理事件流
content_result = None
event_count = 0
for event in stream:
event_count += 1
print(f" [事件 {event_count}] 类型: {event.event}")
if event.event == WorkflowEventType.MESSAGE:
# 打印进度信息
if hasattr(event, 'message') and event.message:
msg = event.message
node_type = getattr(msg, 'node_type', None)
node_title = getattr(msg, 'node_title', None)
node_is_finish = getattr(msg, 'node_is_finish', None)
content = getattr(msg, 'content', None)
print(f" 节点标题: {node_title}")
print(f" 节点类型: {node_type}")
print(f" 是否完成: {node_is_finish}")
print(f" 内容长度: {len(content) if content else 0}")
if node_title:
print(f" ⏳ 执行节点: {node_title} (类型: {node_type})")
# 检查是否为结束节点(使用 node_title 判断)
if node_title == "End" and node_is_finish and content:
print(f" ✓ 工作流执行完成,获取到结果")
content_result = content
break
elif event.event == WorkflowEventType.ERROR:
error_msg = str(event.error) if hasattr(event, 'error') else "Unknown error"
print(f" ✗ 错误事件: {error_msg}")
raise Exception(f"工作流执行错误: {error_msg}")
elif event.event == WorkflowEventType.INTERRUPT:
print(f" ⚠️ 工作流需要交互,暂不支持")
raise Exception("工作流需要人工交互,当前不支持")
if not content_result:
raise Exception("未获取到工作流执行结果")
elapsed = time_module.time() - start
print(f" → 收到完整结果 (耗时: {elapsed:.1f}秒)")
print(f" → 结果数据: {content_result[:200]}...")
# 解析 content 字段(通常包含 JSON 格式的输出)
# content 格式示例: {"output":"```json\n{...}\n```"}
if isinstance(content_result, str):
# 尝试解析为 JSON
try:
content_json = json.loads(content_result)
output = content_json.get("output", content_result)
except json.JSONDecodeError:
output = content_result
# 如果 output 包含 markdown 格式的 JSON提取出来
if isinstance(output, str) and "```json" in output:
import re
json_match = re.search(r'```json\s*\n(.*?)\n```', output, re.DOTALL)
if json_match:
output = json_match.group(1)
# 尝试解析最终的 JSON
data = {"code": 0, "data": {"output": output}}
else:
data = {"code": 0, "data": {"output": content_result}}
# 参考间隔定时脚本的返回结构:{ code: 0, data: { output: ... } }
if isinstance(data, dict) and data.get("code") == 0:
raw_data = data.get("data", {})
if isinstance(raw_data, str):
try:
raw_data = json.loads(raw_data)
except json.JSONDecodeError:
# data.data 为字符串,直接按 LLM 文本解析
return self._parse_llm_response(raw_data)
# 期望 workflow 在 data.output 中返回结果
output = raw_data.get("output", raw_data)
# 如果 output 还是字符串,再次解析
if isinstance(output, str):
try:
output = json.loads(output)
print(f" ✓ Coze 返回的 output 需要二次解析")
except json.JSONDecodeError:
print(f" ⚠️ output 为字符串但无法解析为JSON尝试文本解析")
return self._parse_llm_response(output)
if isinstance(output, dict):
# 如果已经是结构化结果,直接补齐字段
print(f" ✓ Coze 返回结构化数据")
print(f" → 包含字段: {list(output.keys())}")
result = output
required_fields = [
"summary",
"key_findings",
"abnormal_items",
"risk_assessment",
"recommendations",
]
for field in required_fields:
if field not in result:
result[field] = [] if field in [
"key_findings",
"abnormal_items",
"recommendations",
] else "未提供"
print(f" ✓✓ Coze 工作流调用成功!")
return result
if isinstance(output, str):
# output 为文本,通过原有 JSON 解析逻辑处理
return self._parse_llm_response(output)
# 其它类型(列表等),转为字符串后再解析
return self._parse_llm_response(json.dumps(output, ensure_ascii=False))
# code 非 0视为错误
last_error = f"Coze API 返回非0 code: {data}"
print(f" ✗ Coze 返回错误: {last_error}")
except Exception as e: # 包含超时在内的所有请求异常
last_error = str(e)
print(f" ✗ Coze API 调用失败: {last_error}")
if attempt < max_retries - 1:
# 简单的递增退避等待
wait_time = (attempt + 1) * 3
print(f" → 等待 {wait_time} 秒后重试...")
time.sleep(wait_time)
else:
print(f" ✗✗ 已达最大重试次数,放弃调用")
break
print(f" ✗✗ Coze 工作流调用最终失败: {last_error}")
raise Exception(last_error or "Coze API 调用失败")
except Exception as e:
return {
"error": f"Coze API 调用失败: {str(e)}",
"summary": "分析失败",
"key_findings": [],
"abnormal_items": [],
"risk_assessment": "无法评估",
"recommendations": []
}
def _call_ollama(self, prompt: str) -> Dict[str, Any]:
"""调用Ollama API"""
try:
import requests
response = requests.post(
f"{self.ollama_host}/api/generate",
json={
"model": self.model,
"prompt": prompt,
"stream": False
},
timeout=300
)
if response.status_code == 200:
content = response.json().get("response", "")
return self._parse_llm_response(content)
else:
raise Exception(f"Ollama 返回错误: {response.status_code}")
except Exception as e:
return {
"error": f"Ollama API 调用失败: {str(e)}",
"summary": "分析失败",
"key_findings": [],
"abnormal_items": [],
"risk_assessment": "无法评估",
"recommendations": []
}
def _parse_llm_response(self, response: str) -> Dict[str, Any]:
"""解析LLM响应"""
try:
# 尝试提取JSON内容
import re
# 查找JSON代码块
json_match = re.search(r'```(?:json)?\s*(\{.*?\})\s*```', response, re.DOTALL)
if json_match:
json_str = json_match.group(1)
else:
# 查找裸JSON
json_match = re.search(r'\{.*\}', response, re.DOTALL)
if json_match:
json_str = json_match.group(0)
else:
json_str = response
result = json.loads(json_str)
# 验证必需字段
required_fields = ["summary", "key_findings", "abnormal_items", "risk_assessment", "recommendations"]
for field in required_fields:
if field not in result:
result[field] = [] if field in ["key_findings", "abnormal_items", "recommendations"] else "未提供"
return result
except:
# 解析失败,返回原始文本
return {
"summary": "无法解析LLM响应",
"raw_response": response,
"key_findings": [],
"abnormal_items": [],
"risk_assessment": "解析失败",
"recommendations": []
}
def _mock_analysis(self, report_text: str) -> Dict[str, Any]:
"""模拟分析结果"""
return {
"summary": "这是一份血常规检查报告。根据报告内容,各项指标均在正常参考范围内,未发现明显异常。",
"key_findings": [
"白细胞计数: 6.5×10^9/L正常范围",
"红细胞计数: 4.8×10^12/L正常范围",
"血红蛋白: 145 g/L正常范围",
"血小板计数: 220×10^9/L正常范围"
],
"abnormal_items": [],
"risk_assessment": "低风险。所有检测指标均在正常范围内,未发现需要关注的异常项。建议定期体检,保持健康生活方式。",
"recommendations": [
"继续保持良好的生活习惯",
"定期进行健康体检(建议每年一次)",
"保持均衡饮食和适量运动",
"如有不适症状,及时就医"
],
"note": "这是一个模拟的分析结果。实际使用时请配置 OpenAI API 或本地 Ollama 模型。"
}