Fiware Orion Context Broker: Restrictions on subscriptions - fiware

Does Orion support restrictions on subscriptions? Ex. I want to receive context updates only when temperature > 30

That functionality is not implemented in NGSIv1, but planned for NGSIv2 (see conditions field in "Subscriptions" at the NGSIv2 draft specification). However, it has not been yet implemented in the last Orion version at the time of writting this (0.25.0).
EDIT: this functionality has been finally implemented in Orion 0.27.0, eg:
POST /v2/subscriptions
...
{
"subject": {
"entities": [
{
"idPattern": ".*",
"type": "device"
}
],
"condition": {
"attributes": [ "temperature" ],
"expression": {
"q": "temperature>30"
}
}
},
"notification": {
"callback": "http://foo.bar:5050/notify",
"attributes": [ ]
},
"expires": "2050-04-05T14:00:00.00Z"
}

Related

Fiware Orion MQTT notification not working (anymore)

I don’t know where to look anymore, maybe someone has an idea what’s going wrong?
I created an MQTT subscription on my Orion Context Broker:
{
"description": "Subscription to notify of all WaterQualityObserved changes",
"subject": {
"entities": [{
"idPattern": ".*",
"type": "WaterQualityObserved"
}],
"condition": {
"attrs": []
}
},
"notification": {
"mqtt": {
"url": "mqtt://127.0.0.1:1883",
"topic": "water-quality-observed-changed"
}
}
}
I have both my Orion Context Broker and Mosquitto MQTT broker running locally in Docker containers.
I get this when listing the subscriptions in my Orion CB:
[
{
"id": "633bf12fe929777b6a60242b",
"description": "MQTT subscription to notify of all WaterQualityObserved changes",
"status": "active",
"subject": {
"entities": [
{
"idPattern": ".*",
"type": "WaterQualityObserved"
}
],
"condition": {
"attrs": []
}
},
"notification": {
"timesSent": 3,
"lastNotification": "2022-10-04T08:47:55.000Z",
"attrs": [],
"onlyChangedAttrs": false,
"attrsFormat": "normalized",
"mqtt": {
"url": "mqtt://127.0.0.1:1883",
"topic": "water-quality-observed-changed",
"qos": 0
},
"lastFailure": "2022-10-04T08:47:55.000Z",
"failsCounter": 3,
"covered": false
}
}
]
As you can see “timesSent” augments when I PATCH the entity.
The strange thing is it worked before!
Any idea what I’m doing wrong?
Thanks.
Guy
The "The strange thing is it worked before!" sentence make me think it has to do with connectivity between container. I'd suggest to review all the involved connectivity (Orion -> MQTT broker, MQTT broker -> your MQTT subscriber). If that doesn't help, a re-deploy of all the docker containers could help.

FIWARE - Orion Context Broker as Context Provider

I'm having a hard time understanding how context providers work in the Orion Context Broker.
I followed the examples in the step-by-step guide written by Jason Fox. However, I still do not exactly get what happens in the background and how the context broker exactly creates the POST from the registration. Here is what I am trying to do:
I do have a WeatherStation that provides sensor data for a neighborhood.
{
"id": "urn:ngsi-ld:WeatherStation:001",
"type": "Device:WeatherStation",
"temperature": {
"type": "Number",
"value": 20.5,
"metadata": {}
},
"windspeed": {
"type": "Number",
"value": 60.0,
"metadata": {}
}
}
Now I like the WeatherStation to be a context provider for all buildings.
{
"id": "urn:ngsi-ld:building:001",
"type": "Building"
}
Here is the registration that I try to use.
{
"id": null,
"description": "Random Weather Conditions",
"provider": {
"http": {
"url": "http://localhost:1026/v2"
},
"supportedForwardingMode": "all"
},
"dataProvided": {
"entities": [
{
"id": "null",
"idPattern": ".*",
"type": "Building",
"typePattern": null
}
],
"attrs": [
"temperature",
"windspeed"
],
"expression": null
},
"status": "active",
"expires": null,
"forwardingInformation": null
}
The context broker accepts both entities and the registration without any error.
Since I have a multi-tenant setup I use one fiware_service for the complete neighborhood but every building would later have a seperate fiware_servicepath. Hence, the weatherstation has a different servicepath than the building. Although I also tried to put them both on the same path.
For now I used the same headers for all entities.
{
"fiware-service": "filip",
"fiware-servicepath": "/testing"
}
Here is the log of the context broker (version: 3.1.0):
INFO#2021-09-23T19:17:17.944Z logTracing.cpp[212]: Request forwarded (regId: 614cd2b511c25270060d873a): POST http://localhost:1026/v2/op/query, request payload (87 bytes): {"entities":[{"idPattern":".*","type":"Building"}],"attrs":["temperature","windspeed"]}, response payload (2 bytes): [], response code: 200
INFO#2021-09-23T19:17:17.944Z logTracing.cpp[130]: Request received: POST /v2/op/query?options=normalized%2Ccount&limit=1000, request payload (55 bytes): {"entities": [{"idPattern": ".*", "type": "Building"}]}, response code: 200
The log says that it receives the request and forwards it as expected. However, as I understand it this would simply point to the same building entity again. Hence, it is somehow a circular forwarding. I also cannot tell anything about the headers of the request.
I do not understand how the forwarded request from the building can actually query the weather station for information. When I query my building I still only receive the entity with no own properties:
{
"id": "urn:ngsi-ld:building:001",
"type": "Building"
}
I also tried to vary the url of the registration but with no success.
Is this scenario actually possible with the current implementation? It would be very useful
Is there any example for this including also the headers?
I know that I could simply use reference but that would put more work on the user.
Thanks for any help on this.
It is messy, but you could achieve this via a subscription. Hold the weather station as a separate entity in the context broker and poll or push updates into the entity. The subscription would fire whenever the data changes and make two NGSI requests:
Find all entities which have a Relationship servicedBy=WeatherStationX
Run an upsert on all entities to add a Property to each entity:
{
"temperature" : {
"type" : "Property",
"value" : 7,
"unitCode": "CEL",
"observedAt": "XXXXX",
"providedBy": "WeatherStation1"
}
}
Where observedAt comes either from the payload of the weather station or the notification timestamp.
Within the existing IoT Agents, provisioning the link attribute allows a device to propagate measures to a second entity (e.g. this Thermometer entity is measuring temperature for an associated Building entity)
{
"entity_type": "Device",
"resource": "/iot/d",
"protocol": "PDI-IoTA-UltraLight",
..etc
"attributes": [
{"object_id": "l", "name": "temperature", "type":"Float",
"metadata":{
"unitCode":{"type": "Text", "value" :"CEL"}
}
}
],
"static_attributes": [
{
"name": "controlledAsset",
"type": "Relationship",
"value": "urn:ngsi-ld:Building:001",
"link": {
"attributes": ["temperature"],
"name": "providedBy",
"type": "Building"
}
}
]
}
At the moment the logic just links direct one-to-one, but it would be possible to raise a PR to check for an Array and update multiple entities in an upsert - the relevant section of code is here

IoT Agent for a JSON - Sensor sends measures already in NGSI

We have a FIWARE based architecture that uses the IoT Agent for a JSON based protocol.
We have a sensor that sends measures, whose format is already NGSI.
I thought the behavior of the agent was to recognize the NGSI format and manipulate the data so that the final result is correct.
Instead, the current result is that the value on Orion becomes the full NGSI.
e.g.
Attribute on Orion Entity:
"altitude": {
"type": "number",
"value": "12",
"metadata": {
"TimeInstant": {
"type": "ISO8601",
"value": "2019-10-16T09:01:40.460Z"
}
}
}
Send:
{
"altitude": {
"value": "22"
}
}
Result:
"altitude": {
"type": "number",
"value": {
"value": "22"
},
"metadata": {
"TimeInstant": {
"type": "ISO8601",
"value": "2019-10-16T09:08:50.307Z"
}
}
}
Is it correct ?
The purpose of the IOTA (well, one of them :) is to translate measures send by the device to NGSI information at Context Broker. Thus, at device-IOTA level the device sends:
{ <measure_name>: <measure_value> }
So the IOTA looks for the attribute corresponding to <measure_name> (which, in the case no mapping exists, corresponds with just <measure_name>) and update its value with <measure_value>.
In your example, I understand <measure_name> is "altitude" and the <measure_value> is a JSON object { "value": "22" }. I understand also you don't have measure-attribute mapping in place, so the name of the attribute at Context Broker is "altitude", which receives an update with value { "value": "22" }.
So everything seems to be normal, although maybe what you want is to send "22" as value at device-IOTA interface instead of { "value": "22" }.

Orion CB output regarding provisioned device

I have noticed that upon querying Orion CB, while it is working with provisioned devices and having IoT Agent receive HTTP and MQTT messages, it will always output all the values written in the quotation marks:
{
"id": "sensor_data",
"type": "Sensor",
"ActiveTime": {
"type": "Seconds",
"value": "17703",
"metadata": {
"TimeInstant": {
"type": "ISO8601",
"value": "2018-07-04T13:32:27.357Z"
}
}
},
"Distance": {
"type": "Number",
"value": "312",
"metadata": {
"TimeInstant": {
"type": "ISO8601",
"value": "2018-07-04T13:32:27.413Z"
}
}
}
}
However, if to work with only entities in Orion CB, it is possible to receive actual values (like in the example in the manual):
{
"id": "Room1",
"pressure": {
"metadata": {},
"type": "Integer",
"value": 720
},
"temperature": {
"metadata": {},
"type": "Float",
"value": 23
},
"type": "Room"
}
Sometimes, I need to receive the actual value from my sensor in order to format it and use in further applications, but they are in quotation marks, which makes it a little difficult.
Is it possible to somehow change?(maybe in device provisioning), or it really should be that way regarding devices?
Thanks in advance!
EDIT 1
This is the way I provisioned the device:
{
"devices": [
{
"device_id": "sensor_data",
"entity_name": "sensor_data",
"entity_type": "Sensor",
"transport": "MQTT",
"timezone": "Europe/Helsinki",
"attributes": [
{ "object_id": "act", "name": "ActiveTime", "type": "Seconds"},
{ "object_id": "dst", "name": "Distance", "type": "Number"}
]
}
]
}
And this is how the MQTT messages are sent from my sensor (I have set up the topics for IoT Agent to understand them)
/123456789/sensor_data/attrs/act 12
/123456789/sensor_data/attrs/dst 322
123456789 is the API Key I have set here.
This situation tipycally happens when IoT Agents uses NGSIv1 to push data to Context Broker, given that NGSIv1 always "string-fy" any attribute value. Recently, the ability to use NGSIv2 (which doesn't have this limitatino) was introduced in IoT Agents.
In order to solve your problem you have to:
Use a recent IOTA-UL version (the current one from master branch will work)
Enable NGSIv2 in configuration as explained in documentation. This is done in the config.js file:
config.iota = {
...
contextBroker: {
...
ngsiVersion: 'v2'
}
...
}
or using environament variable IOTA_CB_NGSI_VERSION=v2 for the IOTA-UL process.
Enable autocast as explained in documentation. This is done in config.js file:
config.iota = {
...
autocast: true,
...
}
or using environament variable IOTA_AUTOCAST=true for the IOTA-UL process.
Set the right type for each attribute at provision time. The documentation here) provides the right types:
Type "Number" for integer or float numbers
Type "Boolean" for boolean
Type "None" for null
Thus, in your case the provisioning for Distance is ok, but for ActiveTime you should use also Number as type.

How to check if name already exists? Azure Ressource Manager Template

is it possible to check, in an ARM Template, if the name for my Virtual Machine already exists?
I am developing a Solution Template for the Azure Marketplace. Maybe it is possible to set a paramter in the UiDefinition uniqe?
The goal is to reproduce this green Hook
A couple notes...
VM Names only need to be unique within a resourceGroup, not within the subscription
Solution Templates must be deployed to empty resourceGroups, so collisions with existing resources aren't possible
For solution templates the preference is that you simply name the VMs for the user, rather than asking - use something that is appropriate for the workload (e.g. jumpbox) - not all solutions do this but we're trying to improve that experience
Given that it's not likely we'll ever build a control that checks for naming collisions on resources without globally unique constraints.
That help?
This looks impossible, according to the documentation.
There are no validation scenarious.
I assume that you should be using the Microsoft.Common.TextBox UI element in your createUiDefinition.json.
I have tried to reproduce a green check by creating a simple createUiDefinition.json as below with a Microsoft.Common.TextBox UI element as shown below.
{
"$schema": "https://schema.management.azure.com/schemas/0.1.2-preview/CreateUIDefinition.MultiVm.json",
"handler": "Microsoft.Compute.MultiVm",
"version": "0.1.2-preview",
"parameters": {
"basics": [
{
"name": "textBoxA",
"type": "Microsoft.Common.TextBox",
"label": "VM Name",
"defaultValue": "",
"toolTip": "Please enter a VM name",
"constraints": {
"required": true
},
"visible": true
}
],
"steps": [],
"outputs": {}
}
}
I am able to reproduce the green check beside the VM Name textbox as shown below:
However, this green check DOES NOT imply the VM Name is Available.
This is because based on my testing, even if I use an existing VM Name in the same subscription, it is still showing the green check.
Based on the official documented constraints that are supported by the Microsoft.Common.TextBox UI element, it DOES NOT VALIDATE Name Availability.
Hope this helps!
While bmoore's point is correct that it's unlikely you would ever need this for a VM (nor is there an API for it), there are other compute resources that do have global naming requirements.
As of 2022 this concept is possible now with the use of the ArmApiControl UI element. It allows you to call ARM apis as part of validation in the createUiDefinition.json. Here is an example using the check name API for an Azure App service.
{
"$schema": "https://schema.management.azure.com/schemas/0.1.2-preview/CreateUIDefinition.MultiVm.json#",
"handler": "Microsoft.Azure.CreateUIDef",
"version": "0.1.2-preview",
"parameters": {
"basics": [
{}
],
"steps": [
{
"name": "domain",
"label": "Domain Names",
"elements": [
{
"name": "domainInfo",
"type": "Microsoft.Common.InfoBox",
"visible": true,
"options": {
"icon": "Info",
"text": "Pick the domain name that you want to use for your app."
}
},
{
"name": "appServiceAvailabilityApi",
"type": "Microsoft.Solutions.ArmApiControl",
"request": {
"method": "POST",
"path": "[concat(subscription().id, '/providers/Microsoft.Web/checknameavailability?api-version=2021-02-01')]",
"body": "[parse(concat('{\"name\":\"', concat('', steps('domain').domainName), '\", \"type\": \"Microsoft.Web/sites\"}'))]"
}
},
{
"name": "domainName",
"type": "Microsoft.Common.TextBox",
"label": "Domain Name Word",
"toolTip": "The name of your app service",
"placeholder": "yourcompanyname",
"constraints": {
"validations": [
{
"regex": "^[a-zA-Z0-9]{4,30}$",
"message": "Alphanumeric, between 4 and 30 characters."
},
{
"isValid": "[not(equals(steps('domain').appServiceAvailabilityApi.nameAvailable, false))]",
"message": "[concat('Error with the url: ', steps('domain').domainName, '. Reason: ', steps('domain').appServiceAvailabilityApi.reason)]"
},
{
"isValid": "[greater(length(steps('domain').domainName), 4)]",
"message": "The unique domain suffix should be longer than 4 characters."
},
{
"isValid": "[less(length(steps('domain').domainName), 30)]",
"message": "The unique domain suffix should be shorter than 30 characters."
}
]
}
},
{
"name": "section1",
"type": "Microsoft.Common.Section",
"label": "URLs to be created:",
"elements": [
{
"name": "domainExamplePortal",
"type": "Microsoft.Common.TextBlock",
"visible": true,
"options": {
"text": "[concat('https://', steps('domain').domainName, '.azurewebsites.net - The main app service URL')]"
}
}
],
"visible": true
}
]
}
],
"outputs": {
"desiredDomainName": "[steps('domain').domainName]"
}
}
}
You can copy the above code and test it in the createUiDefinition.json sandbox azure provides.