dify/api/core/chain/main_chain_builder.py
2023-05-15 08:51:32 +08:00

117 lines
4.6 KiB
Python

from typing import Optional, List
from langchain.callbacks import SharedCallbackManager
from langchain.chains import SequentialChain
from langchain.chains.base import Chain
from langchain.memory.chat_memory import BaseChatMemory
from core.agent.agent_builder import AgentBuilder
from core.callback_handler.agent_loop_gather_callback_handler import AgentLoopGatherCallbackHandler
from core.callback_handler.dataset_tool_callback_handler import DatasetToolCallbackHandler
from core.callback_handler.main_chain_gather_callback_handler import MainChainGatherCallbackHandler
from core.chain.chain_builder import ChainBuilder
from core.constant import llm_constant
from core.conversation_message_task import ConversationMessageTask
from core.tool.dataset_tool_builder import DatasetToolBuilder
class MainChainBuilder:
@classmethod
def to_langchain_components(cls, tenant_id: str, agent_mode: dict, memory: Optional[BaseChatMemory],
conversation_message_task: ConversationMessageTask):
first_input_key = "input"
final_output_key = "output"
chains = []
chain_callback_handler = MainChainGatherCallbackHandler(conversation_message_task)
# agent mode
tool_chains, chains_output_key = cls.get_agent_chains(
tenant_id=tenant_id,
agent_mode=agent_mode,
memory=memory,
dataset_tool_callback_handler=DatasetToolCallbackHandler(conversation_message_task),
agent_loop_gather_callback_handler=chain_callback_handler.agent_loop_gather_callback_handler
)
chains += tool_chains
if chains_output_key:
final_output_key = chains_output_key
if len(chains) == 0:
return None
for chain in chains:
# do not add handler into singleton callback manager
if not isinstance(chain.callback_manager, SharedCallbackManager):
chain.callback_manager.add_handler(chain_callback_handler)
# build main chain
overall_chain = SequentialChain(
chains=chains,
input_variables=[first_input_key],
output_variables=[final_output_key],
memory=memory, # only for use the memory prompt input key
)
return overall_chain
@classmethod
def get_agent_chains(cls, tenant_id: str, agent_mode: dict, memory: Optional[BaseChatMemory],
dataset_tool_callback_handler: DatasetToolCallbackHandler,
agent_loop_gather_callback_handler: AgentLoopGatherCallbackHandler):
# agent mode
chains = []
if agent_mode and agent_mode.get('enabled'):
tools = agent_mode.get('tools', [])
pre_fixed_chains = []
agent_tools = []
for tool in tools:
tool_type = list(tool.keys())[0]
tool_config = list(tool.values())[0]
if tool_type == 'sensitive-word-avoidance':
chain = ChainBuilder.to_sensitive_word_avoidance_chain(tool_config)
if chain:
pre_fixed_chains.append(chain)
elif tool_type == "dataset":
dataset_tool = DatasetToolBuilder.build_dataset_tool(
tenant_id=tenant_id,
dataset_id=tool_config.get("id"),
response_mode='no_synthesizer', # "compact"
callback_handler=dataset_tool_callback_handler
)
if dataset_tool:
agent_tools.append(dataset_tool)
# add pre-fixed chains
chains += pre_fixed_chains
if len(agent_tools) == 1:
# tool to chain
tool_chain = ChainBuilder.to_tool_chain(tool=agent_tools[0], output_key='tool_output')
chains.append(tool_chain)
elif len(agent_tools) > 1:
# build agent config
agent_chain = AgentBuilder.to_agent_chain(
tenant_id=tenant_id,
tools=agent_tools,
memory=memory,
dataset_tool_callback_handler=dataset_tool_callback_handler,
agent_loop_gather_callback_handler=agent_loop_gather_callback_handler
)
chains.append(agent_chain)
final_output_key = cls.get_chains_output_key(chains)
return chains, final_output_key
@classmethod
def get_chains_output_key(cls, chains: List[Chain]):
if len(chains) > 0:
return chains[-1].output_keys[0]
return None