Files
LangBot/src/langbot/pkg/provider/runners/difysvapi.py
T
marun 2d63d528c6 refactor(dify): Optimize the Dify API output parsing and workflow processing logic (#2027)
- Add the _extract_dify_text_output method to uniformly handle the parsing of Dify output content

- Modify the content extraction method for the answer node in workflow mode

- Add workflow mode detection logic to support the workflow_started event

- Handle error state checks upon completion of the workflow

- Improve the message chunking logic for both basic and workflow modes

- Add a mechanism to capture answer content upon completion of a workflow node
2026-03-05 15:15:40 +08:00

769 lines
30 KiB
Python

from __future__ import annotations
import typing
import json
import uuid
import base64
import mimetypes
from langbot.pkg.provider import runner
from langbot.pkg.core import app
import langbot_plugin.api.entities.builtin.provider.message as provider_message
from langbot.pkg.utils import image
import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
from langbot.libs.dify_service_api.v1 import client, errors
import httpx
@runner.runner_class('dify-service-api')
class DifyServiceAPIRunner(runner.RequestRunner):
"""Dify Service API 对话请求器"""
dify_client: client.AsyncDifyServiceClient
def __init__(self, ap: app.Application, pipeline_config: dict):
self.ap = ap
self.pipeline_config = pipeline_config
valid_app_types = ['chat', 'agent', 'workflow']
if self.pipeline_config['ai']['dify-service-api']['app-type'] not in valid_app_types:
raise errors.DifyAPIError(
f'不支持的 Dify 应用类型: {self.pipeline_config["ai"]["dify-service-api"]["app-type"]}'
)
api_key = self.pipeline_config['ai']['dify-service-api']['api-key']
self.dify_client = client.AsyncDifyServiceClient(
api_key=api_key,
base_url=self.pipeline_config['ai']['dify-service-api']['base-url'],
)
def _process_thinking_content(
self,
content: str,
) -> tuple[str, str]:
"""处理思维链内容
Args:
content: 原始内容
Returns:
(处理后的内容, 提取的思维链内容)
"""
remove_think = self.pipeline_config['output'].get('misc', '').get('remove-think')
thinking_content = ''
# 从 content 中提取 <think> 标签内容
if content and '<think>' in content and '</think>' in content:
import re
think_pattern = r'<think>(.*?)</think>'
think_matches = re.findall(think_pattern, content, re.DOTALL)
if think_matches:
thinking_content = '\n'.join(think_matches)
# 移除 content 中的 <think> 标签
content = re.sub(think_pattern, '', content, flags=re.DOTALL).strip()
# 3. 根据 remove_think 参数决定是否保留思维链
if remove_think:
return content, ''
else:
# 如果有思维链内容,将其以 <think> 格式添加到 content 开头
if thinking_content:
content = f'<think>\n{thinking_content}\n</think>\n{content}'.strip()
return content, thinking_content
def _extract_dify_text_output(self, value: typing.Any) -> str:
"""Extract text content from Dify output payload."""
if value is None:
return ''
if isinstance(value, dict):
content = value.get('content')
if isinstance(content, str):
return content
return json.dumps(value, ensure_ascii=False)
if isinstance(value, str):
text = value.strip()
if not text:
return ''
try:
parsed = json.loads(text)
except json.JSONDecodeError:
return value
if isinstance(parsed, dict) and isinstance(parsed.get('content'), str):
return parsed['content']
return value
return str(value)
async def _preprocess_user_message(self, query: pipeline_query.Query) -> tuple[str, list[dict]]:
"""预处理用户消息,提取纯文本,并将图片/文件上传到 Dify 服务
Returns:
tuple[str, list[dict]]: 纯文本和上传后的文件描述(包含 type 与 id)
"""
plain_text = ''
upload_files: list[dict] = []
user_tag = f'{query.session.launcher_type.value}_{query.session.launcher_id}'
async def upload_file_bytes(file_name: str, file_bytes: bytes, content_type: str) -> str:
file_name = file_name or 'file'
content_type = content_type or 'application/octet-stream'
file = (file_name, file_bytes, content_type)
resp = await self.dify_client.upload_file(file, user_tag)
return resp['id']
async def download_file(file_url: str) -> tuple[bytes, str]:
"""Download file from url (supports data url)."""
async with httpx.AsyncClient() as client_session:
resp = await client_session.get(file_url)
resp.raise_for_status()
content_type = (
resp.headers.get('content-type') or mimetypes.guess_type(file_url)[0] or 'application/octet-stream'
)
return resp.content, content_type
def _detect_file_type(content_type: str) -> str:
"""Map MIME to dify file type."""
if content_type and content_type.startswith('image/'):
return 'image'
if content_type and content_type.startswith('audio/'):
return 'audio'
if content_type and content_type.startswith('video/'):
return 'video'
return 'document'
if isinstance(query.user_message.content, list):
for ce in query.user_message.content:
if ce.type == 'text':
plain_text += ce.text
elif ce.type == 'image_base64':
image_b64, image_format = await image.extract_b64_and_format(ce.image_base64)
file_bytes = base64.b64decode(image_b64)
image_id = await upload_file_bytes(f'img.{image_format}', file_bytes, f'image/{image_format}')
upload_files.append({'type': 'image', 'id': image_id})
elif ce.type == 'file_url':
file_url = getattr(ce, 'file_url', None)
file_name = getattr(ce, 'file_name', None) or 'file'
try:
file_bytes, content_type = await download_file(file_url)
file_id = await upload_file_bytes(file_name, file_bytes, content_type)
file_type = _detect_file_type(content_type)
upload_files.append({'type': file_type, 'id': file_id})
except Exception as e:
self.ap.logger.warning(f'dify file upload failed: {e}')
elif ce.type == 'file_base64':
file_name = getattr(ce, 'file_name', None) or 'file'
header, b64_data = ce.file_base64.split(',', 1)
content_type = 'application/octet-stream'
if ';' in header:
content_type = header.split(';')[0][5:] or content_type
file_bytes = base64.b64decode(b64_data)
file_id = await upload_file_bytes(file_name, file_bytes, content_type)
file_type = _detect_file_type(content_type)
upload_files.append({'type': file_type, 'id': file_id})
elif isinstance(query.user_message.content, str):
plain_text = query.user_message.content
plain_text = plain_text if plain_text else self.pipeline_config['ai']['dify-service-api']['base-prompt']
return plain_text, upload_files
async def _chat_messages(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.Message, None]:
"""调用聊天助手"""
cov_id = query.session.using_conversation.uuid or None
query.variables['conversation_id'] = cov_id
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
mode = 'basic' # 标记是基础编排还是工作流编排
basic_mode_pending_chunk = ''
inputs = {}
inputs.update(query.variables)
chunk = None # 初始化chunk变量,防止在没有响应时引用错误
async for chunk in self.dify_client.chat_messages(
inputs=inputs,
query=plain_text,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
conversation_id=cov_id,
files=files,
timeout=120,
):
self.ap.logger.debug('dify-chat-chunk: ' + str(chunk))
if chunk['event'] == 'workflow_started':
mode = 'workflow'
if mode == 'workflow':
if chunk['event'] == 'node_finished':
if chunk['data']['node_type'] == 'answer':
answer = self._extract_dify_text_output(chunk['data']['outputs'].get('answer'))
content, _ = self._process_thinking_content(answer)
yield provider_message.Message(
role='assistant',
content=content,
)
elif mode == 'basic':
if chunk['event'] == 'message':
basic_mode_pending_chunk += chunk['answer']
elif chunk['event'] == 'message_end':
content, _ = self._process_thinking_content(basic_mode_pending_chunk)
yield provider_message.Message(
role='assistant',
content=content,
)
basic_mode_pending_chunk = ''
if chunk is None:
raise errors.DifyAPIError('Dify API 没有返回任何响应,请检查网络连接和API配置')
query.session.using_conversation.uuid = chunk['conversation_id']
async def _agent_chat_messages(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.Message, None]:
"""调用聊天助手"""
cov_id = query.session.using_conversation.uuid or None
query.variables['conversation_id'] = cov_id
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
ignored_events = []
inputs = {}
inputs.update(query.variables)
pending_agent_message = ''
chunk = None # 初始化chunk变量,防止在没有响应时引用错误
async for chunk in self.dify_client.chat_messages(
inputs=inputs,
query=plain_text,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
response_mode='streaming',
conversation_id=cov_id,
files=files,
timeout=120,
):
self.ap.logger.debug('dify-agent-chunk: ' + str(chunk))
if chunk['event'] in ignored_events:
continue
if chunk['event'] == 'agent_message' or chunk['event'] == 'message':
pending_agent_message += chunk['answer']
else:
if pending_agent_message.strip() != '':
pending_agent_message = pending_agent_message.replace('</details>Action:', '</details>')
content, _ = self._process_thinking_content(pending_agent_message)
yield provider_message.Message(
role='assistant',
content=content,
)
pending_agent_message = ''
if chunk['event'] == 'agent_thought':
if chunk['tool'] != '' and chunk['observation'] != '': # 工具调用结果,跳过
continue
if chunk['tool']:
msg = provider_message.Message(
role='assistant',
tool_calls=[
provider_message.ToolCall(
id=chunk['id'],
type='function',
function=provider_message.FunctionCall(
name=chunk['tool'],
arguments=json.dumps({}),
),
)
],
)
yield msg
if chunk['event'] == 'message_file':
if chunk['type'] == 'image' and chunk['belongs_to'] == 'assistant':
# 检查URL是否已经是完整的连接
if chunk['url'].startswith('http://') or chunk['url'].startswith('https://'):
image_url = chunk['url']
else:
base_url = self.dify_client.base_url
if base_url.endswith('/v1'):
base_url = base_url[:-3]
image_url = base_url + chunk['url']
yield provider_message.Message(
role='assistant',
content=[provider_message.ContentElement.from_image_url(image_url)],
)
if chunk['event'] == 'error':
raise errors.DifyAPIError('dify 服务错误: ' + chunk['message'])
if chunk is None:
raise errors.DifyAPIError('Dify API 没有返回任何响应,请检查网络连接和API配置')
query.session.using_conversation.uuid = chunk['conversation_id']
async def _workflow_messages(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.Message, None]:
"""调用工作流"""
if not query.session.using_conversation.uuid:
query.session.using_conversation.uuid = str(uuid.uuid4())
query.variables['conversation_id'] = query.session.using_conversation.uuid
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
ignored_events = ['text_chunk', 'workflow_started']
inputs = { # these variables are legacy variables, we need to keep them for compatibility
'langbot_user_message_text': plain_text,
'langbot_session_id': query.variables['session_id'],
'langbot_conversation_id': query.variables['conversation_id'],
'langbot_msg_create_time': query.variables['msg_create_time'],
}
inputs.update(query.variables)
async for chunk in self.dify_client.workflow_run(
inputs=inputs,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
files=files,
timeout=120,
):
self.ap.logger.debug('dify-workflow-chunk: ' + str(chunk))
if chunk['event'] in ignored_events:
continue
if chunk['event'] == 'node_started':
if chunk['data']['node_type'] == 'start' or chunk['data']['node_type'] == 'end':
continue
msg = provider_message.Message(
role='assistant',
content=None,
tool_calls=[
provider_message.ToolCall(
id=chunk['data']['node_id'],
type='function',
function=provider_message.FunctionCall(
name=chunk['data']['title'],
arguments=json.dumps({}),
),
)
],
)
yield msg
elif chunk['event'] == 'workflow_finished':
if chunk['data']['error']:
raise errors.DifyAPIError(chunk['data']['error'])
content, _ = self._process_thinking_content(chunk['data']['outputs']['summary'])
msg = provider_message.Message(
role='assistant',
content=content,
)
yield msg
async def _chat_messages_chunk(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.MessageChunk, None]:
"""调用聊天助手"""
cov_id = query.session.using_conversation.uuid or None
query.variables['conversation_id'] = cov_id
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
mode = 'basic'
basic_mode_pending_chunk = ''
inputs = {}
inputs.update(query.variables)
message_idx = 0
chunk = None # 初始化chunk变量,防止在没有响应时引用错误
is_final = False
think_start = False
think_end = False
remove_think = self.pipeline_config['output'].get('misc', '').get('remove-think')
async for chunk in self.dify_client.chat_messages(
inputs=inputs,
query=plain_text,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
conversation_id=cov_id,
files=files,
timeout=120,
):
self.ap.logger.debug('dify-chat-chunk: ' + str(chunk))
if chunk['event'] == 'workflow_started':
mode = 'workflow'
elif chunk['event'] in ('node_started', 'node_finished', 'workflow_finished'):
# Some Dify deployments may omit workflow_started in streamed chunks.
mode = 'workflow'
if chunk['event'] == 'message':
message_idx += 1
if remove_think:
if '<think>' in chunk['answer'] and not think_start:
think_start = True
continue
if '</think>' in chunk['answer'] and not think_end:
import re
content = re.sub(r'^\n</think>', '', chunk['answer'])
basic_mode_pending_chunk += content
think_end = True
elif think_end:
basic_mode_pending_chunk += chunk['answer']
if think_start:
continue
else:
basic_mode_pending_chunk += chunk['answer']
if chunk['event'] == 'message_end':
is_final = True
elif chunk['event'] == 'workflow_finished':
is_final = True
if chunk['data'].get('error'):
raise errors.DifyAPIError(chunk['data']['error'])
if mode == 'workflow' and chunk['event'] == 'node_finished':
if chunk['data'].get('node_type') == 'answer':
answer = self._extract_dify_text_output(chunk['data'].get('outputs', {}).get('answer'))
if answer:
basic_mode_pending_chunk = answer
if (is_final or message_idx % 8 == 0) and (basic_mode_pending_chunk != '' or is_final):
# content, _ = self._process_thinking_content(basic_mode_pending_chunk)
yield provider_message.MessageChunk(
role='assistant',
content=basic_mode_pending_chunk,
is_final=is_final,
)
if chunk is None:
raise errors.DifyAPIError('Dify API 没有返回任何响应,请检查网络连接和API配置')
query.session.using_conversation.uuid = chunk['conversation_id']
async def _agent_chat_messages_chunk(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.MessageChunk, None]:
"""调用聊天助手"""
cov_id = query.session.using_conversation.uuid or None
query.variables['conversation_id'] = cov_id
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
ignored_events = []
inputs = {}
inputs.update(query.variables)
pending_agent_message = ''
chunk = None # 初始化chunk变量,防止在没有响应时引用错误
message_idx = 0
is_final = False
think_start = False
think_end = False
remove_think = self.pipeline_config['output'].get('misc', '').get('remove-think')
async for chunk in self.dify_client.chat_messages(
inputs=inputs,
query=plain_text,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
response_mode='streaming',
conversation_id=cov_id,
files=files,
timeout=120,
):
self.ap.logger.debug('dify-agent-chunk: ' + str(chunk))
if chunk['event'] in ignored_events:
continue
if chunk['event'] == 'agent_message':
message_idx += 1
if remove_think:
if '<think>' in chunk['answer'] and not think_start:
think_start = True
continue
if '</think>' in chunk['answer'] and not think_end:
import re
content = re.sub(r'^\n</think>', '', chunk['answer'])
pending_agent_message += content
think_end = True
elif think_end or not think_start:
pending_agent_message += chunk['answer']
if think_start and not think_end:
continue
else:
pending_agent_message += chunk['answer']
elif chunk['event'] == 'message_end':
is_final = True
else:
if chunk['event'] == 'agent_thought':
if chunk['tool'] != '' and chunk['observation'] != '': # 工具调用结果,跳过
continue
message_idx += 1
if chunk['tool']:
msg = provider_message.MessageChunk(
role='assistant',
tool_calls=[
provider_message.ToolCall(
id=chunk['id'],
type='function',
function=provider_message.FunctionCall(
name=chunk['tool'],
arguments=json.dumps({}),
),
)
],
)
yield msg
if chunk['event'] == 'message_file':
message_idx += 1
if chunk['type'] == 'image' and chunk['belongs_to'] == 'assistant':
# 检查URL是否已经是完整的连接
if chunk['url'].startswith('http://') or chunk['url'].startswith('https://'):
image_url = chunk['url']
else:
base_url = self.dify_client.base_url
if base_url.endswith('/v1'):
base_url = base_url[:-3]
image_url = base_url + chunk['url']
yield provider_message.MessageChunk(
role='assistant',
content=[provider_message.ContentElement.from_image_url(image_url)],
is_final=is_final,
)
if chunk['event'] == 'error':
raise errors.DifyAPIError('dify 服务错误: ' + chunk['message'])
if message_idx % 8 == 0 or is_final:
yield provider_message.MessageChunk(
role='assistant',
content=pending_agent_message,
is_final=is_final,
)
if chunk is None:
raise errors.DifyAPIError('Dify API 没有返回任何响应,请检查网络连接和API配置')
query.session.using_conversation.uuid = chunk['conversation_id']
async def _workflow_messages_chunk(
self, query: pipeline_query.Query
) -> typing.AsyncGenerator[provider_message.MessageChunk, None]:
"""调用工作流"""
if not query.session.using_conversation.uuid:
query.session.using_conversation.uuid = str(uuid.uuid4())
query.variables['conversation_id'] = query.session.using_conversation.uuid
plain_text, upload_files = await self._preprocess_user_message(query)
files = [
{
'type': f['type'],
'transfer_method': 'local_file',
'upload_file_id': f['id'],
}
for f in upload_files
]
ignored_events = ['workflow_started']
inputs = { # these variables are legacy variables, we need to keep them for compatibility
'langbot_user_message_text': plain_text,
'langbot_session_id': query.variables['session_id'],
'langbot_conversation_id': query.variables['conversation_id'],
'langbot_msg_create_time': query.variables['msg_create_time'],
}
inputs.update(query.variables)
messsage_idx = 0
is_final = False
think_start = False
think_end = False
workflow_contents = ''
remove_think = self.pipeline_config['output'].get('misc', '').get('remove-think')
async for chunk in self.dify_client.workflow_run(
inputs=inputs,
user=f'{query.session.launcher_type.value}_{query.session.launcher_id}',
files=files,
timeout=120,
):
self.ap.logger.debug('dify-workflow-chunk: ' + str(chunk))
if chunk['event'] in ignored_events:
continue
if chunk['event'] == 'workflow_finished':
is_final = True
if chunk['data']['error']:
raise errors.DifyAPIError(chunk['data']['error'])
if chunk['event'] == 'text_chunk':
messsage_idx += 1
if remove_think:
if '<think>' in chunk['data']['text'] and not think_start:
think_start = True
continue
if '</think>' in chunk['data']['text'] and not think_end:
import re
content = re.sub(r'^\n</think>', '', chunk['data']['text'])
workflow_contents += content
think_end = True
elif think_end:
workflow_contents += chunk['data']['text']
if think_start:
continue
else:
workflow_contents += chunk['data']['text']
if chunk['event'] == 'node_started':
if chunk['data']['node_type'] == 'start' or chunk['data']['node_type'] == 'end':
continue
messsage_idx += 1
msg = provider_message.MessageChunk(
role='assistant',
content=None,
tool_calls=[
provider_message.ToolCall(
id=chunk['data']['node_id'],
type='function',
function=provider_message.FunctionCall(
name=chunk['data']['title'],
arguments=json.dumps({}),
),
)
],
)
yield msg
if messsage_idx % 8 == 0 or is_final:
yield provider_message.MessageChunk(
role='assistant',
content=workflow_contents,
is_final=is_final,
)
async def run(self, query: pipeline_query.Query) -> typing.AsyncGenerator[provider_message.Message, None]:
"""运行请求"""
if await query.adapter.is_stream_output_supported():
msg_idx = 0
if self.pipeline_config['ai']['dify-service-api']['app-type'] == 'chat':
async for msg in self._chat_messages_chunk(query):
msg_idx += 1
msg.msg_sequence = msg_idx
yield msg
elif self.pipeline_config['ai']['dify-service-api']['app-type'] == 'agent':
async for msg in self._agent_chat_messages_chunk(query):
msg_idx += 1
msg.msg_sequence = msg_idx
yield msg
elif self.pipeline_config['ai']['dify-service-api']['app-type'] == 'workflow':
async for msg in self._workflow_messages_chunk(query):
msg_idx += 1
msg.msg_sequence = msg_idx
yield msg
else:
raise errors.DifyAPIError(
f'不支持的 Dify 应用类型: {self.pipeline_config["ai"]["dify-service-api"]["app-type"]}'
)
else:
if self.pipeline_config['ai']['dify-service-api']['app-type'] == 'chat':
async for msg in self._chat_messages(query):
yield msg
elif self.pipeline_config['ai']['dify-service-api']['app-type'] == 'agent':
async for msg in self._agent_chat_messages(query):
yield msg
elif self.pipeline_config['ai']['dify-service-api']['app-type'] == 'workflow':
async for msg in self._workflow_messages(query):
yield msg
else:
raise errors.DifyAPIError(
f'不支持的 Dify 应用类型: {self.pipeline_config["ai"]["dify-service-api"]["app-type"]}'
)