arc53--docsgpt/deployment/optional/docker-compose.optional.sandbox.yaml

# Optional code-execution sandbox overlay.
#
# Sandboxed code execution (the `code_executor` / `artifact_generator` tools) is
# an OPT-IN feature and is NOT part of the default stack. This overlay adds the
# `docsgpt-sandbox` runner (a Jupyter Kernel Gateway; sessions are in-process
# kernels, never child containers, and the Docker socket is NOT mounted) and
# wires the app to it.
#
# Apply on top of the base stack (order matters -- base first):
#   docker compose -f deployment/docker-compose.yaml \
#     -f deployment/optional/docker-compose.optional.sandbox.yaml up
#
# REQUIRED: set a shared gateway token before starting. The runner's gateway
# authenticates every HTTP + WebSocket request with it (so kernel code cannot
# reach the gateway control API over loopback -- enumerate/kill sibling kernels
# or bypass the session cap), and the app sends it as `Authorization: token`.
# Compose fails to start if it is unset. Put it in `deployment/.env` or export it:
#   export SANDBOX_GATEWAY_AUTH_TOKEN=$(openssl rand -hex 32)
#
# SECURITY POSTURE (single trust domain): all sessions share this one
# container/uid and are isolated by working directory only -- sibling workspaces
# are readable and kernels share one address space. The kernelspec scrubs secrets
# from the kernel env, and the runner sits on the internal `sandbox-net` +
# `sandbox-egress` only (NOT the `default` net), so it has no Docker-DNS route to
# redis/postgres. Two residual gaps remain, exactly as documented in the egress
# overlay: (a) internet/host/RFC1918/metadata egress is open until you ALSO layer
# docker-compose.optional.sandbox-egress.yaml; (b) the runner shares sandbox-net
# with backend/worker (its control path), so on `AUTH_TYPE=none` it can reach the
# API unauthenticated -- run real auth and/or the egress overlay's host-firewall
# DROP. For untrusted multi-tenant workloads use the Daytona backend
# (SANDBOX_BACKEND=daytona, a per-session VM) or the Kubernetes manifests, whose
# NetworkPolicy blocks the internal path too.

services:
  backend:
    environment:
      # Code-execution runner reached over HTTP + WebSocket (no docker socket).
      - SANDBOX_GATEWAY_URL=http://docsgpt-sandbox:8888
      # Select the runner's env-scrubbing kernelspec (distinct name; never
      # shadowed by the stock "python3" spec).
      - SANDBOX_KERNEL_NAME=docsgpt-python
      # Shared secret the app sends as `Authorization: token <...>`. Must match
      # the runner's token below; compose errors if it is unset.
      - SANDBOX_GATEWAY_AUTH_TOKEN=${SANDBOX_GATEWAY_AUTH_TOKEN:?set SANDBOX_GATEWAY_AUTH_TOKEN to a shared gateway token}
    networks:
      - default
      - sandbox-net

  worker:
    environment:
      - SANDBOX_GATEWAY_URL=http://docsgpt-sandbox:8888
      - SANDBOX_KERNEL_NAME=docsgpt-python
      - SANDBOX_GATEWAY_AUTH_TOKEN=${SANDBOX_GATEWAY_AUTH_TOKEN:?set SANDBOX_GATEWAY_AUTH_TOKEN to a shared gateway token}
    networks:
      - default
      - sandbox-net

  docsgpt-sandbox:
    build: ./sandbox
    mem_limit: ${SANDBOX_MEMORY:-1g}
    cpus: ${SANDBOX_CPUS:-1.0}
    pids_limit: 256
    read_only: true
    environment:
      # The gateway REQUIRES this and fails closed if unset (see gateway-launch.sh).
      # Do NOT add `env_file: ../.env` here -- the runner needs no other app secret.
      - SANDBOX_GATEWAY_AUTH_TOKEN=${SANDBOX_GATEWAY_AUTH_TOKEN:?set SANDBOX_GATEWAY_AUTH_TOKEN to a shared gateway token}
      # Keep Jupyter's runtime/connection files on the writable tmpfs.
      - JUPYTER_RUNTIME_DIR=/tmp/jupyter-runtime
      - JUPYTER_DATA_DIR=/tmp/jupyter-data
    tmpfs:
      # Per-session workspaces (/tmp/docsgpt-sandbox/<session_id>) and Jupyter
      # runtime files live on tmpfs; the root FS is read-only everywhere else.
      - /tmp
    networks:
      # Reachable by backend/worker over the internal sandbox-net; internet egress
      # (runtime pip install, etc.) via the dedicated sandbox-egress net. NOT on
      # `default`: the egress overlay cuts internet by flipping sandbox-egress to
      # internal, without severing the control path.
      - sandbox-net
      - sandbox-egress

networks:
  # Control plane between backend/worker and the runner. internal:true => no
  # internet route on this net; the runner egresses via sandbox-egress.
  sandbox-net:
    internal: true
  # The runner's outbound internet route. Internet-facing by default so runtime
  # pip install works; docker-compose.optional.sandbox-egress.yaml flips it to
  # internal and forces egress through a deny-private proxy for SSRF containment.
  sandbox-egress: {}