spud 8204dcbb20
fix(mcp): invalidate cache only for effective MCP config changes (#5750)
* fix(mcp): avoid cache resets for unrelated config changes

extensions_config.json carries MCP servers, skills and middleware settings, but the MCP cache treated any whole-file signature change as MCP state change, so toggling a skill retired every cached tool and closed all pooled sessions.

Record a snapshot of the effective MCP slice (enabled servers' parsed config plus mcpInterceptors) and retire MCP state only when that slice changes. Hand the exact config revision to tool discovery so a change during discovery cannot publish tools built from a superseded revision, and add a non-initializing refresh entry point so disabling the last enabled server still converges the cache and pool on the next tool assembly.

* docs(mcp): align cache guide and restore error diagnostics

Review feedback on #5750 flagged three non-blocking issues: the MCP module guide still described the pre-semantic-snapshot invalidation contract; the tools.py sanitization covered every exception in the MCP block, discarding diagnostics for failures that cannot carry resolved credentials; and _is_cache_stale()'s docstring presented it as a pure predicate despite adopting a new file signature.

Narrow the type-only logging to ExtensionsConfig.from_file() and restore logger.exception() for tool caching, pool cleanup and plugin filtering, with a regression test asserting the message and traceback survive. Document the effective-MCP-slice comparison, the stable config handoff to discovery, refresh_mcp_cache_if_active() and the _initialized_without_config handling in the module guide, and note the signature-adoption side effect in the docstring.

* fix(mcp): unify config normalization and verify signatures

Review follow-up on #5750.

- Normalize mcpInterceptors (bare string == single-element list; missing key == empty list) and the type/transport alias through one shared module used by the tools cache, the interceptor builder and the durable-task config snapshot, so equivalent spellings no longer retire tools/sessions or raise McpTaskConfigurationError.
- Treat a resolved-path switch as a signal to re-read the effective MCP slice instead of an invalidation reason: an identical slice adopts the new path and signature and keeps pooled sessions.
- Refuse to publish or adopt a signature whose sha256 digest is missing ((mtime, size, None) from a file that could not be read).
- Sync the English and Chinese MCP user docs with the effective-config comparison, and document that the Gateway admin reset stays unconditional.

* docs(mcp): note the unverifiable-signature fail-closed branch

A present config file whose content cannot be hashed is treated as stale, unlike a deleted file which keeps the last-known-good cache. Record that asymmetry in the module guide.

* docs(mcp): scope the no-hash rationale to never-initialized processes

The cost-free early return in refresh_mcp_cache_if_active() only covers a process that never published an MCP cache. A process that did publish one (including an empty cache from the zero-server or LangGraph Studio lazy-init path) still pays one stat+sha256 per tool assembly. Correct the rationale in the docstring and the matching comment in get_available_tools().
2026-09-24 17:19:01 +08:00
..
2026-01-14 09:58:53 +08:00
2026-02-10 22:07:25 +08:00

DeerFlow Frontend

Like the original DeerFlow 1.0, we would love to give the community a minimalistic and easy-to-use web interface with a more modern and flexible architecture.

Tech Stack

Quick Start

Prerequisites

  • Node.js 22+
  • pnpm 10.26.2+

Installation

# Install dependencies
pnpm install

# Copy environment variables
cp .env.example .env
# Edit .env with your configuration

Development

# Start development server
pnpm dev

# The app will be available at http://localhost:3000

Build & Test

# Type check
pnpm typecheck

# Check formatting
pnpm format

# Apply formatting
pnpm format:write

# Lint
pnpm lint

# Run unit tests
pnpm test

# One-time setup: install Playwright Chromium browser
pnpm exec playwright install chromium

# Run E2E tests (builds and starts production server automatically)
pnpm test:e2e

# Build for production
pnpm build

# Start production server
pnpm start

Site Map

├── /                    # Landing page
├── /chats               # Chat list
├── /chats/new           # New chat page
└── /chats/[thread_id]   # A specific chat page

Configuration

Environment Variables

Key environment variables (see .env.example for full list):

# Backend API URL (optional, uses local Next.js/nginx proxy by default)
NEXT_PUBLIC_BACKEND_BASE_URL="http://localhost:8001"
# LangGraph-compatible API URL (optional, uses local Next.js/nginx proxy by default)
NEXT_PUBLIC_LANGGRAPH_BASE_URL="http://localhost:8001/api"

Project Structure

tests/
├── e2e/                    # E2E tests (Playwright, Chromium, mocked backend)
└── unit/                   # Unit tests (mirrors src/ layout)
src/
├── app/                    # Next.js App Router pages
│   ├── api/                # API routes
│   ├── showcase/           # Allowlisted public read-only demos
│   ├── workspace/          # Main workspace pages
│   └── mock/               # Mock/demo pages
├── components/             # React components
│   ├── ui/                 # Reusable UI components
│   ├── workspace/          # Workspace-specific components
│   ├── landing/            # Landing page components
│   └── ai-elements/        # AI-related UI elements
├── core/                   # Core business logic
│   ├── api/                # API client & data fetching
│   ├── artifacts/          # Artifact management
│   ├── config/              # App configuration
│   ├── i18n/               # Internationalization
│   ├── mcp/                # MCP integration
│   ├── messages/           # Message handling
│   ├── models/             # Data models & types
│   ├── settings/           # User settings
│   ├── skills/             # Skills system
│   ├── threads/            # Thread management
│   ├── todos/              # Todo system
│   └── utils/              # Utility functions
├── hooks/                  # Custom React hooks
├── lib/                    # Shared libraries & utilities
├── server/                 # Server-side code
│   └── better-auth/        # Authentication setup and session helpers
└── styles/                 # Global styles

Scripts

Command Description
pnpm dev Start development server with Webpack
pnpm build Build for production
pnpm start Start production server
pnpm test Run unit tests with Rstest
pnpm test:e2e Run E2E tests with Playwright
pnpm format Check formatting with Prettier
pnpm format:write Apply formatting with Prettier
pnpm lint Run ESLint
pnpm lint:fix Fix ESLint issues
pnpm typecheck Run TypeScript type checking
pnpm check Run both lint and typecheck

Development Notes

  • Uses pnpm workspaces (see packageManager in package.json)
  • Webpack is the default development bundler until the upstream Turbopack PostCSS worker leak is fixed in a stable Next.js release (#5132). Set DEER_FLOW_DEV_BUNDLER=turbo to opt in to Turbopack for local diagnosis, or DEER_FLOW_DEV_BUNDLER=webpack to select Webpack explicitly. Reconsider the default after the stable fix is verified on macOS arm64 and Linux.
  • Environment validation can be skipped with SKIP_ENV_VALIDATION=1 (useful for Docker)
  • Backend API URLs are optional; nginx proxy is used by default in development

License

MIT License. See LICENSE for details.