m365-sim

Drop-in Microsoft Graph API mock server for testing. Returns realistic JSON fixtures for 33+ endpoints across 3 cloud targets and 3 scenarios.

Use This Instead of Real M365

Point your Graph API client at http://localhost:8888 instead of https://graph.microsoft.com. That's it.

What to Change in Your Project

1. Base URL: Replace https://graph.microsoft.com with http://localhost:8888
2. Auth token: Use any string — Bearer test works. The server accepts any Bearer token without validation.
3. No other changes needed. Responses match real Graph API shapes exactly (@odata.context, value arrays, singleton objects).

Start the Server

# Clone and run (one-time setup)
cd ~/github/m365-sim
python3 -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
python server.py --port 8888

# Or with Docker
docker build -t m365-sim .
docker run -d -p 8888:8888 m365-sim

Pick Your Scenario

Flag	What You Get
--scenario greenfield	Fresh tenant, zero controls (default)
--scenario hardened	Full CMMC posture: 8 CA policies, FIDO2, compliant devices
--scenario partial	Mid-deployment: 3 CA policies, partial auth
--cloud gcc-moderate	graph.microsoft.com, Contoso Defense LLC (default)
--cloud gcc-high	graph.microsoft.us, Contoso Defense Federal LLC
--cloud commercial-e5	graph.microsoft.com, Contoso Corp

python server.py --scenario hardened --cloud gcc-high --port 8888

Quick Test

# Health check (no auth)
curl http://localhost:8888/health

# Get users
curl -H "Authorization: Bearer test" http://localhost:8888/v1.0/users

# Get users via beta API
curl -H "Authorization: Bearer test" http://localhost:8888/beta/users

# Filter
curl -H "Authorization: Bearer test" "http://localhost:8888/v1.0/users?\$filter=userType eq 'Member'"

# Simulate throttling
curl -H "Authorization: Bearer test" "http://localhost:8888/v1.0/users?mock_status=429"

Stateful Mode (Deploy-Then-Verify)

python server.py --stateful --port 8888

POST/PATCH now mutate state. POST /v1.0/_reset restores baseline.

Full Documentation

See docs/guide.md for the complete endpoint list, query parameter support ($filter, $expand, $top), write operations, error simulation, Docker Compose setup, and runtime overrides.