OpenVSP MCP Server

"""Core subprocess helpers for OpenVSP/VSPAero automation.""" from __future__ import annotations import os import subprocess import tempfile from pathlib import Path from shutil import which from typing import Iterable from .models import OpenVSPRequest, OpenVSPResponse, VSPCommand def _resolve_binary(env_var: str, default_name: str) -> str: candidate = os.environ.get(env_var) if candidate: return candidate resolved = which(default_name) if resolved: return resolved return default_name OPENVSP_BIN = _resolve_binary("OPENVSP_BIN", "vsp") VSPAERO_BIN = _resolve_binary("VSPAERO_BIN", "vspaero") def execute_openvsp(request: OpenVSPRequest) -> OpenVSPResponse: """Run OpenVSP (and optionally VSPAero) using the provided request.""" with tempfile.TemporaryDirectory(prefix="openvsp_mcp_") as tmpdir: workdir = Path(tmpdir) script_path = _write_script(request, workdir) try: result = subprocess.run( [OPENVSP_BIN, "-script", str(script_path)], check=False, capture_output=True, ) except FileNotFoundError as exc: # pragma: no cover raise RuntimeError("OpenVSP binary not found") from exc if result.returncode not in _OK_EXIT_CODES: message = result.stderr.decode("utf-8", errors="ignore").strip() if not message: message = result.stdout.decode("utf-8", errors="ignore").strip() or "OpenVSP script execution failed" raise RuntimeError(message) vspaero_output: str | None = None if request.run_vspaero: try: aero = subprocess.run( [VSPAERO_BIN, request.geometry_file, request.case_name], check=False, capture_output=True, ) except FileNotFoundError as exc: # pragma: no cover raise RuntimeError("VSPAero binary not found") from exc if aero.returncode != 0: message = aero.stderr.decode("utf-8", errors="ignore").strip() if not message: message = aero.stdout.decode("utf-8", errors="ignore").strip() or "VSPAero execution failed" raise RuntimeError(message) vspaero_output = str(Path(request.case_name).with_suffix(".adb")) return OpenVSPResponse(script_path=str(script_path), result_path=vspaero_output) def _ensure_statement(command: str) -> str: stripped = command.strip() if not stripped.endswith(";"): stripped = f"{stripped};" return stripped def _write_script(request: OpenVSPRequest, working_dir: Path) -> Path: script_path = working_dir / "automation.vspscript" commands: Iterable[VSPCommand] = request.set_commands or [] script_lines = [ "// Auto-generated by openvsp-mcp", "void main() {", " ClearVSPModel();", f" ReadVSPFile(\"{request.geometry_file}\");", ] for command in commands: script_lines.append(f" {_ensure_statement(command.command)}") script_lines.extend( [ " Update();", f" SetVSP3FileName(\"{request.geometry_file}\");", f" WriteVSPFile(\"{request.geometry_file}\", SET_ALL);", "}", ] ) script_path.write_text("\n".join(script_lines) + "\n", encoding="utf-8") return script_path _OK_EXIT_CODES = {0, 160, 224} __all__ = ["execute_openvsp", "OPENVSP_BIN", "VSPAERO_BIN", "_OK_EXIT_CODES", "_write_script"]