Event Engine User Manual

Comprehensive reference for all triggers, conditions, actions, and settings.

Overview

Event Engine is an IFTTT-style automation engine that runs directly on your Axis camera as an ACAP application. It replaces and extends the built-in Axis event system with a flexible rule engine that reacts to camera events, schedules, MQTT messages, and webhooks, then responds with notifications, camera commands, logic operations, and more.

Each Rule is composed of three parts:

• Triggers — what starts the rule (one or more, evaluated as OR or AND)
• Conditions — optional checks that must pass before actions run
• Actions — what happens when the rule fires (run in sequence)

Rules take effect immediately when saved — no restart required.

Installation

1. Download the latest .eap file from Releases. Choose the file that matches your camera architecture:
   • aarch64 — newer Axis cameras (ARTPEC-8, most cameras from 2020+)
   • armv7hf — older Axis cameras (ARTPEC-6/7)
2. In your camera's web interface, go to Apps.
3. Click Add app and upload the .eap file.
4. Once installed, start the app.

Accessing the UI

Open a browser and navigate to:

http://<camera-ip>/local/acap_event_engine/index.html

You will be prompted for camera credentials (admin-level account required). The UI has five sections accessible via the top tab bar:

• Rules — create, manage, and monitor your automation rules
• Event Log — per-rule firing history
• Variables — named variables and counters
• Settings — MQTT broker, SMTP, location, proxy, and backup
• API Docs — interactive OpenAPI documentation

How Rules Work

A rule fires when any of its triggers activate (OR logic by default, switchable to AND). Before actions run, conditions are checked — by default all must evaluate to true (AND logic), but condition logic can be switched to OR so that any passing condition allows execution. Actions then execute in sequence from top to bottom.

Creating a Rule

1. Click + New Rule on the Rules tab (or choose a starter from Templates).
2. Enter a descriptive rule name.
3. Click + Add Trigger and choose a trigger type from the dropdown.
4. Optionally click + Add Condition to add guards that must pass.
5. Click + Add Action and configure what should happen.
6. Click Save Rule. The rule is active immediately.

Rule Settings

Managing Rules

Each rule card shows the rule name, trigger and action badges, and a last-fired timestamp. Actions available from the rule card:

• Edit — open the rule in the editor
• Duplicate — clone the rule as a starting point
• Enable / Disable — toggle without deleting
• Fire Now — manually trigger the rule once for testing
• Delete — permanently remove the rule

Use the search bar at the top of the Rules tab to filter rules by name. Use Export / Import to download or upload rules as JSON. Individual rules can also be exported from their action menu.

Triggers

A trigger defines what event starts a rule. You can add multiple triggers to a single rule; all triggers of the same type stack as OR conditions by default.

Device Event

Fires when any device event occurs — motion detection, thermometry, tampering, I/O state changes, analytics, air quality, and more. Events are loaded live from the device and presented in a searchable dropdown.

Options

Schedule

Fires on a time-based schedule. Four schedule modes are available:

MQTT Message

Fires when an incoming MQTT message arrives on a matching topic. Requires the MQTT broker to be configured in Settings.

Available variables injected by this trigger: {{trigger.topic}}, {{trigger.payload}}.

HTTP Webhook

Fires when an external system sends an HTTP POST request to the camera with a matching token. Each webhook trigger has its own unique secret token (up to 120 characters).

POST http://<camera-ip>/local/acap_event_engine/fire
Content-Type: application/json

{
  "token": "my-secret-token",
  "payload": { "source": "doorbell", "floor": 2 }
}

Values from payload are injected as {{trigger.KEY}} variables (e.g. {{trigger.source}}, {{trigger.floor}}).

I/O Input

Fires on a digital input port state change.

Counter Threshold

Fires when a named counter value crosses a configured threshold. Useful for "fire after 10 motion events" type logic in combination with the Increment Counter action.

Rule Chain

Fires when another named rule executes. Use this to build multi-step workflows where one rule triggers another.

AOA Scenario

Fires when an Axis Object Analytics scenario generates an event. Requires the AOA application to be installed and configured on the camera.

Variables injected: {{trigger.scenario_id}}, {{trigger.object_class}}.

Conditions

Conditions act as guards. By default (AND logic), all conditions must evaluate to true before actions run. With OR logic (configurable in Rule Settings), any single passing condition is sufficient. If no conditions pass, the rule silently does nothing for that firing.

Time Window

Only allow the rule to fire between two times of day.

I/O State

Check the current state of a digital I/O port before proceeding.

Counter Compare

Compare a named counter value against a threshold.

Variable Compare

Compare a named variable against a string value.

HTTP Check

Make an HTTP request and pass the condition only if the response matches expectations.

AOA Occupancy

Poll Axis Object Analytics occupancy for a scenario and pass only if the count satisfies a configured threshold.

Day / Night

Pass only during daytime (after sunrise) or nighttime (after sunset). Uses the sunrise/sunset engine with the latitude/longitude configured in Location settings.

The rule editor shows today's computed sunrise and sunset times for the configured location.

Device Event State

Check the current state of any device event by polling the device’s event instances.

Actions

Actions run in sequence from top to bottom when a rule fires and all conditions pass. You can drag action rows to reorder them. All text fields support {{variable}} substitution — see Dynamic Variables.

HTTP Request

Send an HTTP request to any URL.

MQTT Publish

Publish a message to an MQTT topic. Requires the MQTT broker to be configured in Settings.

Slack

Send a message to a Slack channel via an incoming webhook.

Teams

Send an Adaptive Card to Microsoft Teams via a Power Automate / Workflows webhook.

Telegram

Send a message via the Telegram Bot API.

Email (SMTP)

Send an email. The SMTP server, credentials, and from address are configured once in Settings → Email (SMTP); each action only needs the recipient, subject, and body.

Snapshot Upload

Capture a JPEG from the camera and upload it to a URL.

FTP Upload

Capture a JPEG and upload it to an FTP or SFTP server.

Send Syslog

Write a message to the camera's system log (visible in the camera's system log view).

Recording

Start or stop a recording on the camera.

Overlay Text

Write text on the live video stream.

PTZ Preset

Move the camera to a named preset position. Available presets are loaded from the camera.

Guard Tour

Start or stop a configured PTZ guard tour. Available tours are loaded from the camera and shown in a dropdown.

IR Cut Filter

Force the IR cut filter state.

Privacy Mask

Enable or disable a named privacy mask.

Wiper

Trigger the windshield wiper on cameras that support it (e.g. outdoor housings).

Light Control

Control an Axis illuminator (white light or IR LED).

Audio Clip

Play a named media clip on the camera. Available clips are loaded from the camera.

Siren / Light

Start or stop a named siren/LED profile on devices that support it (e.g. Axis D6310).

I/O Output

Set a digital output port high or low.

Notification Digest

Buffer events and send a batched summary on a configurable interval. Useful for sending hourly summaries instead of individual alerts.

Delay

Pause the action sequence for N seconds before continuing to the next action. Use this to create timed sequences within a rule.

Set Variable

Create or update a named persistent variable stored on the camera. Variables survive restarts.

Increment Counter

Modify a named persistent counter.

Run Rule

Immediately trigger another named rule. Useful for shared action sequences or conditional branching via variable state.

Fire ACAP Event

Fire an ACAP event visible to other Axis applications and built-in action rules on the device.

Device Event Query

Fetch the latest cached data from any device event and inject it as {{trigger.FIELD}} variables for subsequent actions. Used for polling sensor values on a schedule trigger.

Set Device Parameter

Update any camera parameter via param.cgi.

ACAP Control

Start, stop, or restart another installed ACAP application on the camera.

InfluxDB Write

Write a data point to InfluxDB using line protocol.

AOA Get Counts

Fetch accumulated crossline counts from an Axis Object Analytics scenario and inject them as template variables for use in subsequent actions.

Enable Reset after fetch to zero the counters after reading them.

While-Active Actions

Several actions support a While active mode: Recording, Overlay Text, Siren / Light, and I/O Output. When enabled, the action automatically reverses itself (stops recording, clears overlay, stops siren, resets output) when the triggering condition clears.

This is useful for scenarios like "record while motion is detected" or "activate siren while I/O port 1 is high". The rule must use a stateful trigger (e.g. a Device Event that has active/inactive states) for while-active to function correctly.

Rule Templates

Click the Templates button on the Rules tab to browse a library of pre-built starter rules. Templates provide a ready-made configuration that you can customise after applying. Available templates include:

• Device Event → HTTP Webhook
• Device Event → Email Alert
• Device Event → Slack / Teams / Telegram
• Daily Schedule → Syslog
• MQTT Message → Set Variable
• I/O Input → I/O Output
• I/O Input → Siren + MQTT
• Hourly Snapshot → FTP Upload
• Manual → PTZ + Overlay
• Motion → Recording (Business Hours)
• Arm / Disarm System via MQTT (3 rules)
• AOA Object Detection → MQTT
• Schedule → InfluxDB Sensor Write
• Device Event → Notification Digest
• Sunrise / Sunset → IR Cut Filter
• Counter Threshold → Slack Alert

Applying a template opens the rule editor pre-filled with the template's triggers, conditions, and actions. Modify any field before saving.

Dynamic Variables

Most text fields in actions support {{variable}} substitution. Click Insert variable in the rule editor to browse available values for the current trigger type.

Global variables (always available)

Trigger variables (set by the fired trigger)

Named variables and counters

Example — MQTT payload with sensor data:

Camera {{camera.serial}} at {{timestamp}}: {{trigger_json}}

Arm / Disarm Pattern

Use the Variable Compare condition with a variable named system.armed (value "true" or "false") to make rules only fire when the system is armed.

Example rules to implement this (available in the Templates picker):

1. Arm System via MQTT — subscribe to cameras/<serial>/arm, set system.armed = "true"
2. Disarm System via MQTT — same topic, set system.armed = "false"
3. Motion Alert When Armed — motion trigger + Variable Compare condition: system.armed = "true"

You can also arm/disarm via an HTTP webhook, a schedule, an I/O input, or any other trigger.

MQTT Setup

Configure the MQTT broker in Settings → MQTT Broker. The built-in client supports MQTT 3.1.1.

Features:

• QoS 0 and QoS 1 publish
• Wildcard topic subscriptions (+ and #)
• Automatic reconnect with exponential backoff
• TLS/SSL encryption

The Settings tab shows a live connection status indicator next to "MQTT BROKER".

Application Settings

Location

Set the camera's latitude and longitude (decimal degrees). This is required for Sunrise/Sunset triggers and the Day/Night condition to work correctly.

• North latitude is positive (e.g. 59.3293 for Stockholm)
• South latitude is negative (e.g. -33.8688 for Sydney)
• East longitude is positive (e.g. 18.0686)
• West longitude is negative (e.g. -73.9442 for New York)

Email (SMTP)

Configure once and reuse across all email actions.

SOCKS5 Proxy

Route all outbound connections (HTTP actions, HTTP conditions, and MQTT) through a SOCKS5 proxy. Leave blank to connect directly.

Set to localhost:1055 to tunnel all traffic over Axis Tailscale ACAP.

Device Capabilities

The Settings tab automatically detects and displays your camera's capabilities:

• Status cards — total rules, enabled rules, events today
• Device info — model, serial number, IP address, firmware version, engine version
• PTZ — number of presets per channel
• Audio clips — available media clips
• Siren / Light — available profiles
• Privacy masks — configured masks
• Guard tours — configured tours
• Object Analytics (AOA) — installed scenarios
• Installed ACAPs — other ACAP applications on the camera

These capabilities are used to populate dropdowns in the rule editor (PTZ presets, audio clips, siren profiles, guard tours, AOA scenarios, ACAP apps, privacy masks). If a capability is not available on your camera, the corresponding action types will show an empty dropdown.

Event Log

The Event Log tab shows the most recent rule firings. Each entry includes:

• Time — exact timestamp of firing
• Rule — which rule fired
• Result — success or error code
• Details — additional context (trigger data, error message)

Use the rule filter dropdown to scope the log to a single rule. Click Refresh to reload. Click Clear to empty the log.

Variables Tab

The Variables tab shows all named variables and counters currently stored on the camera. You can:

• View the current value of any variable or counter
• Edit a variable value directly
• Delete a variable or counter

Variables are persistent — they survive ACAP restarts and in-place updates.

Backup & Restore

Use the Settings → Backup & Restore section to export your configuration before performing updates or camera replacements.

• Export Rules — download all rules as a JSON file
• Import Rules — upload a previously exported rules JSON
• Export Settings — download MQTT, SMTP, location, and proxy settings
• Import Settings — restore a settings file

Rules can also be exported individually using Export from the rule card's action menu, producing a portable single-rule JSON file that can be shared and imported on any camera.

REST API

All endpoints are under /local/acap_event_engine/ and require HTTP Basic Auth with admin credentials.

For interactive documentation, open API Docs.

Event Engine — MIT License