Simulator Automation

EvenHub Simulator Automation

The simulator exposes an HTTP API on localhost when launched with --automation-port <PORT>.

evenhub-simulator https://my-app.example.com --automation-port 9898

Base URL: http://127.0.0.1:<PORT>

API Reference

Health check

GET /api/ping
→ "pong"

Glasses screenshot

Returns the current LVGL framebuffer as image/png (576×288, RGBA).

GET /api/screenshot/glasses
→ image/png binary (RGBA)

RGBA format — critical for image analysis:

• Background pixels: (R=0, G=255, B=0, A=0) — transparent (alpha = 0)
• Lit/text pixels: (R=0, G=255, B=0, A=255) — opaque (alpha = 255)

Always work in RGBA mode. Do NOT convert to RGB — it drops the alpha channel and makes background pixels indistinguishable from text pixels (both appear as pure green).

from PIL import Image
img = Image.open('glasses.png')  # keep as RGBA — do NOT call img.convert('RGB')
pixels = img.load()
# Lit pixel test:
is_lit = lambda px: px[3] > 0   # alpha > 0

Webview screenshot

Captures the main browser webview using html2canvas. Returns image/png. May take a few seconds; times out after 10s.

GET /api/screenshot/webview
→ image/png binary

Console logs

Returns captured console.* output, uncaught exceptions, unhandled promise rejections, and failed fetch calls from the main webview.

GET /api/console
→ { "entries": [...], "total": N }

Each entry:

{ "id": 0, "level": "log|warn|error|info|debug|trace", "message": "...", "ts": 1712150400000 }

Prefixes for non-console sources:

• [uncaught] ... — uncaught exception
• [unhandledrejection] ... — unhandled promise rejection
• [fetch] ... — failed fetch (non-ok status or network error)

Poll for new entries only:

GET /api/console?since_id=42
→ entries with id > 42

since_id must be a non-negative integer. Passing a negative value (e.g. -1) causes the server to return an error, not an empty list. For the first poll, omit the parameter entirely to retrieve all current entries, then track last_id from the response:

# First poll — no since_id
resp = requests.get(f"{BASE_URL}/api/console")
entries = resp.json()["entries"]
last_id = max((e["id"] for e in entries), default=0)

# Subsequent polls
resp = requests.get(f"{BASE_URL}/api/console?since_id={last_id}")

Clear the buffer:

DELETE /api/console

Timing caution: Startup logs (e.g. a "ready" signal) are emitted once and lost if you clear the buffer before reading them. Pattern: poll for the ready signal first, then clear if needed.

# Safe: check for ready signal BEFORE clearing
poll_until(target="APP_READY")
requests.delete(f"{BASE_URL}/api/console")  # only if you need a clean slate after

Glasses input

Send a touchpad action to the glasses display.

POST /api/input
Content-Type: application/json

{ "action": "up" | "down" | "click" | "double_click" }

Response: { "ok": true }

Actions map to the glasses touchpad:

• up / down — scroll through list items or text
• click — select the current item
• double_click — triggers a system-level double-click event (typically "back" or "dismiss")

Automation workflow

1. Verify the server is running: GET /api/ping
2. Poll for app ready (without clearing console first): look for a known log message.
3. Observe: Use /api/screenshot/glasses (RGBA) or /api/console to check state.
4. Act: Send input via POST /api/input. After each action, wait briefly (~300ms) then confirm state changed.
5. Iterate: Use since_id when polling console to avoid re-reading old entries.

Tips

• The glasses display is 576×288 pixels, monochrome green. Screenshots are RGBA PNGs.
• Input only works when the app has created an active event container. If no container is active, input is silently ignored.
• double_click is typically used to go back or dismiss the current view.
• Allow 4+ seconds after launching the simulator before polling — SDK init and createStartUpPageContainer take time.

Task

$ARGUMENTS