Locust Load Testing for VS Code

This extension helps you scaffold, run, and manage Locust load tests directly from VS Code.
It integrates with Python environments, provides templates, snippets, and an Explorer view for your scenarios.

✨ Features

• Explorer tree view: browse locustfile.py files, user classes, and tasks.
• One-click runs:
  • Run a locustfile in Web UI mode.
  • Run in headless mode.
  • Run specific tasks or tags.
• Environment setup:
  • Detects existing Locust installation.
  • Prompts to create a local locust_env and install Locust (via uv or venv+pip).
• Templates: create a ready-to-use locustfile.py from extension templates.
• Snippets: insert @task, FastHttpUser, and tagged task boilerplates quickly.
• Command Palette integration: run everything via F1 → Locust: ....
• Playground app: optional Flask demo backend to practice against.

🚀 Quick Start Tutorial (Playground + Locust)

This is the fastest way to try the extension with a demo backend.

1. Create environment & install Flask

   uv venv locust_env
   uv pip install flask
   
   
   

2. Run the playground API

   uv run python -m playground_app.locust_playground_app
   

   This starts a fake e-commerce API at: 👉 http://localhost:5000

3. Scaffold a Locust scenario

   In VS Code:

   F1 → Locust: Create Simulation
   

   Pick locustfile.py template. It contains sample tasks against the /, /authenticate, /cart/add, and /checkout/confirm endpoints.

4. Run Locust against the playground

   • Web UI:

     F1 → Locust: Run (Web UI)
     

     Open http://localhost:8089 and start a test against http://localhost:5000.

   • Headless:

     locust -f locustfile.py --headless -u 10 -r 2 -t 1m -H http://localhost:5000
     

     F1 → Locust: Run (Headless)
     

   • By tag:

     F1 → Locust: Run by Tag…
     

🏗️ Architecture Overview

┌─────────────────────┐
│   VS Code Extension │
│  (Locust UI & CLI)  │
└─────────┬───────────┘
          │ Commands (Run, Init, Create, Tags)
          ▼
┌─────────────────────┐
│  Python Environment │
│   (locust_env venv) │
│   Locust installed  │
└─────────┬───────────┘
          │ Locust HTTP load generation
          ▼
┌─────────────────────┐
│  Playground Flask   │
│     Demo App        │
│ (Simulated API)     │
└─────────────────────┘

⚙️ Extension Settings

• locust.path: Path to the Locust CLI (default: locust).
• locust.envFolder: Name of the local Python environment folder (default: locust_env).
• locust.defaultHost: Default host URL for your tests.
• locust.autoSetup: Whether to prompt for setup on activation (prompt | always | never).

⌨️ Snippets

• loctask → Insert a @task function with a request.
• locuser → Boilerplate FastHttpUser class with a simple GET task.
• loctag → Task with a @tag decorator for selective runs.

🧑‍💻 Development (For Contributors)

If you want to hack on the extension itself:

npm install
npm run watch

Then press F5 in VS Code to launch a new Extension Development Host with Locust support.

📝 Release Notes

0.0.1

• Initial release with tree view, templates, snippets, and environment setup flow.
• Added playground Flask app for tutorial-style scenarios.
• Added Quick Start tutorial for end-to-end demo.