Use case 1: Motion detection during the night
Description
We assume that in a factory, several motion sensors are installed in specific areas where usually, there is no activity during the night.
A new detection can be suspicious and a guard must check the place.
The motion sensor publishes a Data message in Live Objects using MQTT protocol each time there is detection with a minimum of 10 sec interval between two detections.
The night time is from 20h to 06h (24h UTC time).
Live Objects features
For this use case, we will use:
-
Alarming: a Simple Event Processing rule associated with a Firing rule
-
Notifications: Triggers & Actions with a SMS notification
Step 1: identifying the Data message format
The Data message sent by the device follows this format:
{
"location": {
"provider": "gps",
"lon": 2.99616,
"lat": 50.21142
},
"model": "demoDevGuide",
"value": {
"motionSensorDetection": 1,
"type":"alert",
"typeId":4,
"version": "1.2.4"
},
"timestamp": "2019-09-06T08:58:10.953Z",
"tags": [
"last_version","areaSouth"
]
}Details about Data message format: see Data model section
The Data message after internal Live Objects enrichment follows this format:
{
"metadata": {
"connector": "mqtt",
"source": "urn:lo:nsid:mqtt:myTest",
"transformation": {
"published": {
"location": {
"provider": "gps",
"lon": 2.99616,
"lat": 50.21142
}
}
},
"group": {
"path": "/",
"id": "root"
},
"network": {
"mqtt": {
"clientId": "urn:lo:nsid:mqtt:myTest"
}
}
},
"streamId": "urn:lo:nsid:mqtt:myTest",
"created": "2021-06-17T14:21:34.036Z",
"extra": {},
"location": {
"provider": "gps",
"alt": null,
"accuracy": null,
"lon": 2.99616,
"lat": 50.21142
},
"model": "demoDevGuide",
"id": "60cb5a6e2b9f5a61388d3fb7",
"value": {
"motionSensorDetection": 1,
"typeId": 4,
"type": "alert",
"version": "1.2.4"
},
"timestamp": "2021-06-17T14:21:34.026Z",
"tags": [
"last_version",
"areaSouth"
]
}Details about Live Objects enricher: see Data enrichment process
Step 2: set the matching rule
The matching rule is using the additional “get_utc_hours” jsonLogic operator to extract the hour value of the timestamp.
{
"name":"matching rule with time condition",
"enabled":true,
"dataPredicate":{
"and":[
{
"==":[
{
"var":"value.motionSensorDetection"
},
1
]
},
{
"or":[
{
">=":[
{
"get_utc_hours":[
{
"var":"timestamp"
}
]
},
20
]
},
{
"<":[
{
"get_utc_hours":[
{
"var":"timestamp"
}
]
},
6
]
}
]
}
]
}
}Details about additional operators: see Additional operators
Step 3: set the firing rule
As the minimum interval is 10 sec between two data messages in case of motion detection, to avoid SMS spam, we define here a firing rule with SLEEP mode in order to repeat the notification with a larger time interval. Here the sleep duration is set to 2 minutes.
{
"name":"firing rule with sleep mode to avoid flooding",
"enabled":true,
"matchingRuleIds":[
"my_matching_rule_id"
],
"aggregationKeys":["metadata.source"],
"firingType":"SLEEP",
"sleepDuration":"PT2M"
}Step 4: set the notification using triggers and actions policy
Here you can find an action policy with the trigger type "matchingFired" linked with the ruleId = the firingRuleId of the rule created in the previous step.
{
"name":"notification by sms for a motion detection during the night",
"enabled":true,
"triggers":{
"matchingFired":{
"version":1,
"filter":{
"ruleIds":[
"my_firing_rule_id"
]
}
}
},
"actions":{
"sms":[
{
"destinationPhoneNumbers":[
"+33612345667"
],
"contentTemplate":"Motion detection! Sensor: {{matchingContext.data.metadata.network.mqtt.clientId}} at {{matchingContext.data.timestamp}}"
}
]
}
}Details about Triggers and actions feature: see Notification
Test it! With this data message from the device: detection at 23:58 UTC:
{
"location": {
"provider": "gps",
"lon": 2.99616,
"lat": 50.21142
},
"model": "demoDevGuide",
"value": {
"motionSensorDetection": 1,
"type":"alert",
"typeId":4,
"version": "1.2.4"
},
"timestamp": "2019-09-06T23:58:10.953Z",
"tags": [
"last_version","areaSouth"
]
}A SMS is sent:
"Motion detection! Sensor: 1234qfre at 2019-09-06T23:58:10.953Z"