Dockerfile.langflow.dev

# Development Dockerfile for building Langflow from source
# Allows building from any Git branch/repo for testing

FROM python:3.12-slim AS builder

# Set environment variables
ENV DEBIAN_FRONTEND=noninteractive
ENV PYTHONUNBUFFERED=1
ENV RUSTFLAGS="--cfg reqwest_unstable"

# Accept build arguments for git repository and branch
ARG GIT_REPO=https://github.com/langflow-ai/langflow.git
ARG GIT_BRANCH=main

# Install system dependencies
# (+) Install uv for faster Python package management (needs root, goes to /usr/local/bin)
# (+) Create non-root group: "langflow"
# (+) Create non-root user: "langflow"
RUN apt-get update && apt-get install -y \
    build-essential \
    curl \
    git \
    ca-certificates \
    gnupg \
    npm \
    rustc cargo pkg-config libssl-dev \
    && rm -rf /var/lib/apt/lists/* \
    && pip install uv \
    && groupadd --gid 103000 langflow \
    && useradd --uid 103000 --gid langflow --no-create-home langflow

# Switch to non-root user: "langflow"
USER langflow
# Create working directory: /app (owned by "langflow")
WORKDIR /app

# Clone the repository and checkout the specified branch
RUN echo "Cloning ${GIT_REPO} branch ${GIT_BRANCH}..." && \
    git clone --depth 1 --branch ${GIT_BRANCH} ${GIT_REPO} /app

# Install backend dependencies
RUN uv sync --frozen --no-install-project --no-editable --extra postgresql

# Build frontend (split into steps to reduce peak memory usage)
WORKDIR /app/src/frontend
# Install dependencies first
RUN npm ci --maxsockets 1
# Build with reduced memory - 2GB should be safer for most systems
RUN NODE_OPTIONS="--max_old_space_size=2048 --max-semi-space-size=128" npm run build
# Copy built frontend
RUN mkdir -p /app/src/backend/base/langflow/frontend && \
    cp -r build/* /app/src/backend/base/langflow/frontend/

# Return to app directory and install the project
WORKDIR /app
RUN uv sync --frozen --no-dev --no-editable --extra postgresql

# Expose ports
EXPOSE 7860

# Start the backend server
CMD ["uv", "run", "langflow", "run", "--host", "0.0.0.0", "--port", "7860"]