A new Flask-based REST API server runs on port 5050 alongside the Cesium visualization server, exposing the full emulator lifecycle over HTTP. This replaces the need for direct CLI interaction and enables integration with external tools, dashboards, and automation pipelines.

Key endpoints:

Method	Endpoint	Description
GET	/api/health	Health check
POST	/api/upload-config	Upload a TOML configuration file
POST	/api/upload-tle	Upload a TLE file
POST	/api/load-config	Stage 1 (load): load config.toml, validate it, and create the nodes. Optional body {"isCzml": true, "isDockercompose": false}
POST	/api/init-scenario	Stage 2 (init/prepare): start/validate the nodes per their type, gate + start the routing protocol selected in the toml’s [Routing] section, and apply the channel shaping — runs in the background. Optional body {"isVM": true, "password": "..."} (isVM=false skips all node/network config and computes contacts/timing only)
GET	/api/scenario	Get current scenario description
POST	/api/write-czml	Generate the CZML file for Cesium
POST	/api/start-vms	Start all VMs
POST	/api/stop-vm/<name>	Stop a specific VM
POST	/api/stop-all-vms	Stop all VMs
DELETE	/api/delete-vm/<name>	Delete a specific VM
DELETE	/api/delete-all-vms	Delete all VMs
POST	/api/compose/up	Start the Docker node containers (docker compose up -d); optional JSON body {"services": ["satellite-1", ...]} to start a subset
POST	/api/compose/down	Stop and remove the Docker node containers (docker compose down)
POST	/api/simulation/start	Stage 3 (start): start only the simulation clock (init must have finished). Also restarts the clock after a natural end. Optional body {"isVM": ..., "password": ...} to override the saved values
POST	/api/visualization/start	Start visualization only
POST	/api/simulation/stop	Stop the run and remove the channel-shaping/routing rules, keeping the loaded scenario so the clock can be re-started. Optional body {"password": "..."}
GET	/api/status	Get system status and simulation progress
POST	/api/reset	Full teardown — stop, remove rules, and wipe all state back to IDLE
GET	/api/help	List all available endpoints

The API tracks system state across the lifecycle (IDLE → CONFIG_LOADED → PREPARING_VMS → RUNNING_SIMULATION → SIMULATION_ENDED) and returns 409 Conflict responses for invalid transitions. The lifecycle is split into three explicit stages:

1. load — parse config.toml, validate, and create the nodes.
2. init / prepare — configure the nodes, install the per-link rules, and apply the channel shaping (the one-time network setup). After this the scenario is ready but the clock is not moving.
3. start — advance the simulation clock only (positions + timing; per-tick network updates when enabled).

Reaching the end of the timeline stops the clock and resets the time marker to zero, but leaves the channel shaping and rules applied (SIMULATION_ENDED). From there, start replays from the reset marker without re-preparing, while stop (or reset) is what actually removes the rules. This keeps the network state intact at the end of a run instead of tearing it down underneath still-running nodes.

To start (launched automatically by SatelliteEmulator.py):

python SatelliteEmulator.py        # starts API + interactive CLI
python SatelliteEmulator.py --web  # API + Cesium web server