fastpyrepl 0.1.1

FastAPI service for executing Python code in session-scoped environments

fastpyrepl

fastpyrepl is a small FastAPI service that executes Python code in session-scoped environments over HTTP.

Install

From pypi:

pip install fastpyrepl

From source:

git clone https://github.com/gjyotin305/fastpyrepl
cd fastpyrepl
pip install .

After install, run the CLI:

fastpyrepl --help

Run the server

Default:

fastpyrepl

Custom host/port:

fastpyrepl --host 127.0.0.1 --port 9000

Enable reload during development:

fastpyrepl --reload

The server starts at http://<host>:<port>.

API Endpoints

GET /health

Check service health.

Example:

curl http://127.0.0.1:8000/health

Response:

{"status":"PYTHON REPL ACTIVE"}

POST /execute

Execute Python code in a session.

Request body:

{
  "code": "print('hello')",
  "context": "optional context string",
  "setup_code": "x = 10",
  "session_id": "optional-session-id",
  "return_locals": true,
  "locals_keys": ["x"]
}

Notes:

• If session_id is omitted, a new one is created and returned.
• Reuse the same session_id to keep variables between calls.
• setup_code runs when a new session is created.

Example:

curl -X POST http://127.0.0.1:8000/execute \
  -H "Content-Type: application/json" \
  -d '{"code":"x = 2\nprint(x)","return_locals":true,"locals_keys":["x"]}'

Response shape:

{
  "stdout": "2\n",
  "stderr": "",
  "locals": {"x": 2},
  "execution_time": 0.001,
  "session_id": "...",
  "error": null
}

POST /reset

Reset one session or all sessions.

Reset one:

curl -X POST http://127.0.0.1:8000/reset \
  -H "Content-Type: application/json" \
  -d '{"session_id":"your-session-id"}'

Reset all:

curl -X POST http://127.0.0.1:8000/reset \
  -H "Content-Type: application/json" \
  -d '{}'

Local development

python3 -m pip install -e .
fastpyrepl --reload

Security warning

This service executes arbitrary Python code. Do not expose it to untrusted users or public networks without sandboxing and strict isolation.