Files
cdsl-cad/backend/app/services/agent_service.py
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2026-08-19 19:34:30 +08:00

363 lines
17 KiB
Python

from __future__ import annotations
import asyncio
import base64
import json
import secrets
from collections.abc import AsyncIterator
from typing import Any
import httpx
from app.models.contracts import ChatMessage
from app.services.engine_service import build_revision, load_engine
from app.services.library import CdslLibrary
from app.services.sse import event
from app.services.storage import WorkspaceStore
from app.settings import ProviderConfig, ProviderModel, Settings
TOOL_SCHEMAS: list[dict[str, Any]] = [
{
"type": "function",
"function": {
"name": "search_cdsl_library",
"description": "Search the official local CDSL library for similar geometry and feature sequences.",
"parameters": {
"type": "object",
"properties": {"query": {"type": "string"}, "limit": {"type": "integer", "minimum": 1, "maximum": 8}},
"required": ["query"],
},
},
},
{
"type": "function",
"function": {
"name": "read_cdsl_reference",
"description": "Read one official CDSL sample by part_id. Use this before creating geometry based on a reference.",
"parameters": {"type": "object", "properties": {"part_id": {"type": "string"}}, "required": ["part_id"]},
},
},
{
"type": "function",
"function": {
"name": "read_current_cdsl",
"description": "Read the current task's latest CDSL before making a natural-language revision.",
"parameters": {"type": "object", "properties": {}, "additionalProperties": False},
},
},
{
"type": "function",
"function": {
"name": "generate_cdsl_model",
"description": "Validate and execute a complete parameterized CDSL model. Use only for explicit CAD generation or revision.",
"parameters": {
"type": "object",
"properties": {
"cdsl": {"type": "object", "description": "Complete cad.cdsl.llm.v1 JSON object."},
"summary": {"type": "string"},
"assumptions": {"type": "array", "items": {"type": "string"}},
},
"required": ["cdsl", "summary"],
},
},
},
]
def text_from_message(message: ChatMessage) -> str:
return "\n".join(part.text or "" for part in message.parts if part.type == "text").strip()
def messages_for_model(messages: list[ChatMessage]) -> list[dict[str, Any]]:
result: list[dict[str, Any]] = []
for message in messages[-20:]:
text = text_from_message(message)
if text:
result.append({"role": message.role, "content": text})
return result
def system_prompt(settings: Settings) -> str:
skill_path = settings.engine_root.parent.parent / "agent" / "skills" / "cad-engine" / "SKILL.md"
skill = skill_path.read_text(encoding="utf-8") if skill_path.is_file() else ""
readme_path = settings.engine_root / "README.md"
engine_readme = readme_path.read_text(encoding="utf-8") if readme_path.is_file() else ""
supported_profiles = ", ".join(sorted(load_engine(settings).SHAPE_GENERATORS))
return f"""You are the CDSL CAD Agent for CDSL CAD Studio.
You generate parameterized CDSL, never raw CAD source code. For new CAD requests:
1. Search the local official CDSL library.
2. Read at least one relevant reference when a match exists.
3. Call generate_cdsl_model only when the request is sufficiently specified.
4. Never claim success unless the tool returns a successful CDSL-only STEP and GLB artifact.
For a revision, call read_current_cdsl first and preserve unrelated features.
Do not output compiler_context, unknown_shape, complex_arc_shape, entities,
contour_edges_mm, or contour_regions_mm. Use only self-contained named profiles
supported by the engine. Ask a concise clarification question when essential
dimensions or intent are missing. Ordinary explanations must not create CAD.
Local skill:
{skill}
Local engine guide:
{engine_readme}
Supported named profile types:
{supported_profiles}
"""
class AgentService:
def __init__(self, settings: Settings, store: WorkspaceStore, library: CdslLibrary) -> None:
self.settings = settings
self.store = store
self.library = library
async def stream(
self,
messages: list[ChatMessage],
conversation_id: str | None,
selected_task_id: str | None,
provider_id: str | None = None,
model_id: str | None = None,
) -> AsyncIterator[bytes]:
latest_user = next((message for message in reversed(messages) if message.role == "user"), None)
if latest_user is None:
yield event("cad_error", {"stage": "request", "message": "A user message is required."})
yield event("done", {})
return
user_text = text_from_message(latest_user)
conversation = self.store.ensure_conversation(conversation_id, selected_task_id)
self.store.append_conversation_message(conversation["conversation_id"], latest_user.model_dump(), selected_task_id)
task_id = selected_task_id or conversation.get("current_task_id") or ""
assistant_parts: list[dict[str, Any]] = []
assistant_id = f"assistant_{secrets.token_hex(8)}"
successful_result: dict[str, Any] | None = None
error_payload: dict[str, Any] | None = None
try:
provider, model = self.settings.resolve_model(provider_id, model_id)
except ValueError as error:
provider = None
model = None
configuration_error = str(error)
else:
configuration_error = ""
if not self.settings.llm_configured or provider is None or model is None:
message = "Agent 尚未配置模型。请设置 CDSL_LLM_BASE_URL、CDSL_LLM_API_KEY 和 CDSL_LLM_MODEL。"
if configuration_error:
message = configuration_error
error_payload = {"stage": "configuration", "message": message}
assistant_parts.append({"type": "data-cad-error", "data": error_payload})
yield event("cad_error", error_payload)
self._persist_assistant(conversation["conversation_id"], assistant_id, assistant_parts, task_id)
yield event("done", {})
return
try:
attachment_message = self._attachment_message(conversation, model)
except ValueError as error:
error_payload = {"stage": "attachment", "message": str(error)}
assistant_parts.append({"type": "data-cad-error", "data": error_payload})
yield event("cad_error", error_payload)
self._persist_assistant(conversation["conversation_id"], assistant_id, assistant_parts, task_id)
yield event("done", {})
return
yield event("progress", {"step": "analyze_request", "label": "分析需求", "status": "running", "message": "正在整理当前会话和 CAD 需求。"})
references: list[str] = []
model_messages: list[dict[str, Any]] = [{"role": "system", "content": system_prompt(self.settings)}]
model_messages.extend(messages_for_model(messages))
if attachment_message:
model_messages.append({"role": "user", "content": attachment_message})
tools = TOOL_SCHEMAS
try:
for iteration in range(8):
response = await self._complete(model_messages, tools, provider, model)
choice = response["choices"][0]["message"]
tool_calls = choice.get("tool_calls") or []
content = str(choice.get("content") or "")
if content:
assistant_parts.append({"type": "text", "text": content})
for chunk in self._chunks(content):
yield event("text_delta", {"text": chunk})
if not tool_calls:
break
model_messages.append(choice)
for call in tool_calls:
name = str(call.get("function", {}).get("name") or "")
arguments = json.loads(call.get("function", {}).get("arguments") or "{}")
yield event("progress", {
"step": name,
"label": self._tool_label(name),
"status": "running",
"message": "Agent 正在调用本地 CAD 工具。",
})
result, generated = await self._run_tool(name, arguments, task_id, user_text, references)
if generated:
task_id = generated["task_id"]
model_messages.append({
"role": "tool",
"tool_call_id": call.get("id", ""),
"content": json.dumps(result, ensure_ascii=False),
})
yield event("progress", {
"step": name,
"label": self._tool_label(name),
"status": "success" if result.get("ok", True) else "error",
"message": result.get("message") or result.get("summary") or "",
})
if generated:
result_payload = {
"taskId": generated["task_id"],
"revisionId": generated["revision_id"],
"cdslPath": generated["cdsl_path"],
"stepPath": generated["step_path"],
"glbPath": generated["glb_path"],
"reportPath": generated["report_path"],
"parametersPath": generated.get("parameters_path"),
"selectorPath": generated.get("selector_path"),
"edgesPath": generated.get("edges_path"),
"summary": generated["summary"],
"referenceIds": generated["reference_ids"],
"engine": generated["engine"],
}
successful_result = result_payload
assistant_parts.append({"type": "data-cad-result", "data": result_payload})
yield event("cad_result", result_payload)
if iteration == 7:
error_payload = {"stage": "agent", "message": "Agent tool loop reached its safety limit."}
assistant_parts.append({"type": "data-cad-error", "data": error_payload})
yield event("cad_error", error_payload)
except Exception as error:
error_payload = {"stage": "agent", "message": str(error)}
assistant_parts.append({"type": "data-cad-error", "data": error_payload})
yield event("cad_error", error_payload)
if task_id:
self.store.ensure_conversation(conversation["conversation_id"], task_id)
if not assistant_parts:
assistant_parts.append({
"type": "text",
"text": "我暂时没有生成可执行的 CAD 结果。请补充尺寸、形状或修改目标。",
})
if successful_result and not any(part.get("type") == "text" for part in assistant_parts):
assistant_parts.insert(0, {"type": "text", "text": f"已生成:{successful_result['summary']}。"})
self._persist_assistant(conversation["conversation_id"], assistant_id, assistant_parts, task_id)
yield event("progress", {"step": "agent_stream", "label": "调用模型和工具", "status": "success", "message": "Agent 请求已完成。"})
yield event("done", {})
def _persist_assistant(
self,
conversation_id: str,
assistant_id: str,
parts: list[dict[str, Any]],
task_id: str,
) -> None:
self.store.append_conversation_message(
conversation_id,
{
"id": assistant_id or f"assistant_{conversation_id}_{len(parts)}",
"role": "assistant",
"parts": parts,
},
task_id or None,
)
async def _complete(
self,
messages: list[dict[str, Any]],
tools: list[dict[str, Any]],
provider: ProviderConfig,
model: ProviderModel,
) -> dict[str, Any]:
url = f"{provider.base_url}/chat/completions"
headers = {"Authorization": f"Bearer {provider.api_key}", "Content-Type": "application/json"}
payload = {"model": model.id, "messages": messages, "tools": tools, "tool_choice": "auto", "temperature": 0.1}
async with httpx.AsyncClient(timeout=self.settings.llm_timeout_s) as client:
response = await client.post(url, headers=headers, json=payload)
if response.status_code >= 400:
raise RuntimeError(f"LLM request failed ({response.status_code}): {response.text[:800]}")
return response.json()
async def _run_tool(self, name: str, arguments: dict[str, Any], task_id: str, request: str, references: list[str]) -> tuple[dict[str, Any], dict[str, Any] | None]:
if name == "search_cdsl_library":
results = self.library.search(str(arguments.get("query") or request), int(arguments.get("limit") or 5))
return {"ok": True, "results": results}, None
if name == "read_cdsl_reference":
part_id = str(arguments.get("part_id") or "")
sample = self.library.read_sample(part_id)
if part_id not in references:
references.append(part_id)
return {"ok": True, "part_id": part_id, "cdsl": sample}, None
if name == "read_current_cdsl":
if not task_id:
return {"ok": False, "message": "No current task exists. This is a new model request."}, None
path = self.store.current_cdsl_path(task_id)
if path is None:
return {"ok": False, "message": "The current task has no successful CDSL revision."}, None
return {"ok": True, "task_id": task_id, "cdsl": json.loads(path.read_text(encoding="utf-8"))}, None
if name == "generate_cdsl_model":
cdsl = arguments.get("cdsl")
if isinstance(cdsl, str):
cdsl = json.loads(cdsl)
if not isinstance(cdsl, dict):
raise ValueError("generate_cdsl_model requires a CDSL JSON object")
summary = str(arguments.get("summary") or "CDSL CAD model")
yieldable = await asyncio.to_thread(
build_revision,
settings=self.settings,
store=self.store,
task_id=task_id or None,
request=request,
cdsl=cdsl,
reference_ids=list(references),
summary=summary,
)
return {"ok": True, "summary": summary, "task_id": yieldable["task_id"], "revision_id": yieldable["revision_id"]}, yieldable
raise ValueError(f"Unknown agent tool: {name}")
@staticmethod
def _chunks(text: str) -> list[str]:
return [text[index:index + 96] for index in range(0, len(text), 96)]
@staticmethod
def _tool_label(name: str) -> str:
return {
"search_cdsl_library": "检索 CDSL 模型库",
"read_cdsl_reference": "读取 CDSL 参考模型",
"read_current_cdsl": "读取当前 CDSL",
"generate_cdsl_model": "生成 CDSL CAD 模型",
}.get(name, "调用 CAD 工具")
def _attachment_message(self, conversation: dict[str, Any], model: ProviderModel) -> list[dict[str, Any]] | str:
attachments = conversation.get("attachments") or []
if not attachments:
return ""
content: list[dict[str, Any]] = [{"type": "text", "text": "The following local attachments are part of the CAD request."}]
for attachment in attachments:
if not isinstance(attachment, dict):
continue
kind = str(attachment.get("kind") or "")
task_id = str(attachment.get("task_id") or "")
relative = str(attachment.get("path") or "")
if not task_id or not relative:
continue
path = self.store.artifact_path(task_id, relative)
if kind == "image":
if not model.vision:
raise ValueError("The selected model does not support images. Choose a vision-capable OpenAI or Kimi model.")
mime = str(attachment.get("mime") or "image/png")
encoded = base64.b64encode(path.read_bytes()).decode("ascii")
content.append({"type": "image_url", "image_url": {"url": f"data:{mime};base64,{encoded}"}})
elif kind == "document":
extracted = str(attachment.get("extracted_path") or "")
if extracted:
text_path = self.store.artifact_path(task_id, extracted)
text = text_path.read_text(encoding="utf-8")[:30_000]
content.append({"type": "text", "text": f"Document {attachment.get('name')}:\n{text}"})
return content