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Welcome to the nVent Nuheat OpenAPI documentation

The nVent Nuheat OpenAPI delivers access for 3rd Party developers to integrate with the nVent Nuheat smart thermostats.

To gain access to the API, first you must contact our support department to get access to a ClientID.

Request access to the API

Swagger documentation

To make your life easier when getting started developing against the API, we have implemented Swagger as our Endpoint and Model documentation tool.
This allows you to explore and test the API right in your browser, with our included test client.

Go to swagger now!

OAuth2


The NuHeat OpenAPI uses OAuth2 and OpenID-Connect as the Authorization methods to the API.
OAuth 2 is an authorization framework that enables a service to grant 3rd party applications access to obtain limited access to a users account via a HTTP service.
This protocol allows third-party applications to request limited access to an HTTP service, either on behalf of a resource owner or by allowing the third-party application to obtain access on its own behalf.
Access is requested by the client, which can be a website, desktop application or a mobile application.

Discovery document

As part of the OpenID Connect standard, a discovery document is available to get an overview of the various endpoints and configurations for the NuHeat Identity(OAuth2) Server.

OpenID Discovery document

OAuth2 concepts:

Grants:
describes a number of grants (“methods”) for a client application to acquire an access token. 
Scopes
provide a way to limit the amount of access that is granted to an access token. It is a lists of identifiers used to specify what access privileges are being requested.
Claims
are name/value pairs that contain information about a user. Profile claims are included that ensures that the request for the user’s info was made using a token that was obtained with the profile scope

Tokens:

Tokens are issued from the OAuth2 server to provide access to the system. Three types exist:

  • id_token: identity information about the user is encoded into the token.
  • access_token: used as bearer tokens, meaning that the bearer can access authorized resources without further identification.
    • Expiration: 1 hour
    • These tokens usually have a short lifespan (dictated by its expiration) for improved security. When the access token expires, the user must authenticate again to get a new access token limiting the exposure of the fact that it’s a bearer token. They last about an hour and cannot be revoked, once issued.
  • refresh_token: used to obtain new access tokens. These will be long-lived while access tokens are short-lived. This allows for long-lived sessions that can be killed if necessary.
    • Expiration: 15 days
    • Refresh tokens extend the connection to the users account, while still allowing revokeability. This allows an authorized application to get a new access token without the users interaction. If the user has revoked access to the 3rd party application, the refresh token is no longer valid. Refresh tokens last about 15-30 days.

Grant types/flows

The NuHeat OpenAPI allows the following grant types:

Implicit

The implicit grant type is optimized for browser-based applications. Either for user authentication-only (both server-side and JavaScript applications), or authentication and access token requests (JavaScript applications).

In the implicit flow, all tokens are transmitted via the browser, and advanced features like refresh tokens are thus not allowed.

Requirements:
  • ClientID
  • Scopes
    • openid
    • openapi

Authorization Code

Authorization code flow was originally specified by OAuth 2, and provides a way to retrieve tokens on a back-channel as opposed to the browser front-channel. It also support client authentication.

While this grant type is supported on its own, it is generally recommended you combine that with identity tokens which turns it into the so called hybrid flow. Hybrid flow gives you important extra features like signed protocol responses.

Requirements:
  • ClientID
  • ClientSecret
  • Scopes
    • offline_access - [Optionally required] Add this if you need to get a refresh token
    • openid
    • openapi

Hybrid

Hybrid flow is a combination of the implicit and authorization code flow - it uses combinations of multiple grant types, most typically code id_token.

In hybrid flow the identity token is transmitted via the browser channel and contains the signed protocol response along with signatures for other artifacts like the authorization code. This mitigates a number of attacks that apply to the browser channel. After successful validation of the response, the back-channel is used to retrieve the access and refresh token.

This is the recommended flow for native applications that want to retrieve access tokens (and possibly refresh tokens as well) and is used for server-side web applications and native desktop/mobile applications.

Requirements:
  • ClientID
  • ClientSecret - In the backchannel request
  • Scopes
    • offline_access - [Optionally required] Add this if you need to get a refresh token
    • openid
    • openapi

Which grant type / grant flow should I choose?

Flow Features

Authorization Code Implicit Hybrid
All tokens returned from authorization endpoint
All tokens returned from token endpoint
Tokens sent via user agent
Client can be authenticated (e.g. using client secret)
Can use refresh tokens
Communication in one round trip
Most communication server-to-server

Response Types by Flow

Flow Response Types
Authorization Code code
Implicit id_token
Implicit id_token token
Hybrid code id_token
Hybrid code token
Hybrid code id_token token

Tables adapted from OpenID Connect 1.0 Core Specification.

Scopes

OpenAPI (openapi)

The OpenAPI Scope, allows access to the OpenAPI on behalf of the authenticated user.

OpenID (openid)

Required by the OpenID standard.

Profile (profile)

Optional - It is possible to call the OpenID Profile endpoint, and get a few claims about the user. We advise to use the OpenAPI’s GetAccount endpoint instead.

Offline Access (offline_access)

Required if you want to receive a refresh token.

Claims

The NuHeat OpenAPI doesn't include many claims in the access token and id token, and the access token itself is more or less only relevant as a bearer token to be sent to the API.

  • Subject (sub)
    • Contains the "subject" of the access_token, in our case it contains the unique userId of the current user.
  • Not before (nbf)
    • Defines that the token is not valid before this time (seconds since Unix Epoch)
  • Expires (exp)
    • Defines that the token is valid until this time (seconds since Unix Epoch)
  • Issuer (who created and signed the token) (iss)
    • Defines who issed the token.
  • Audience (who or what the token is intended for) (aud)
    • List of audiences, will usually contain the API resource eg. openapi.
  • ClientID (client_id)
    • The client id the token is issued to.
  • Scope (scope)
    • List of scopes that the token is granted access to.

Web services


As a 3rd party developer, you have two (2) webservices to talk to.

  • The Identity Server
    • Which handles all OAuth2 protocol communication
    • Responsible for issuing your OAuth2 Access and Refresh tokens.
    • Exists at this address https://identity.mynuheat.com
  • The OpenAPI

Block diagram of Architecture

Webservices structure

Http return codes


The nVent Nuheat OpenAPI only supports json data. That means that it sends and receives the mimetype application/json.

Return codes

Success responses
  • 200 - Success
    • Specifies that the request was a success, and that a there is data in the response body.
  • 204 - No Content
    • Specifies that the request was a success, but there is no data sent back in the response body.
    • This is to save bandwidth.
Error responses
  • 400 - Bad Request
  • 401 - Unauthorized
  • 403 - Forbidden
  • 404 - Not found
  • 500 - Internal server error

The error codes are described more detailed in the error handling section.

Error handling


Error codes

All endpoints can send one of the following errors:

  • 400 - Bad Request
    • If what the client sent could not be validated.
  • 401 - Unauthorized
    • If the client is not authorized to call this method, eg. not logged in.
  • 403 - Forbidden
    • If the client doesn't have the scope for this call.
  • 404 - Not found
    • If a resource is being looked up that doesn't exist, or an endpoint that doesn't exists is being called.
  • 429 - Too many requests
    • If you are hitting the burst and rate limits, you will receive this error code, see Burst and rate limits section.
  • 500 - Internal server error
    • If an unexpected error occured.

The following status codes [400, 500] will return a json response.

Error example

{
    "messages": [
        "Description of the error that occured.",
        "Also this occured"
    ]
}

Models


This section covers everything around the models and how they are related to eachother. Additional information on the models can be found on the swagger page, at the bottom of the page.

Diagram

All the models in the OpenApi are related to each other. With thermostat pointing towards a group id, then there are more info on that specific group, when you do a GET request on that specific id.

Versioning


Multiple Version

The nVent Nuheat OpenAPI supports multiple versions, which means that you as a developer, do not have to worry about the release of new features or breaking changes.
New features added in the same API version will always be backwards compatible and any breaking changes will be in a new major version of the api.


Version 1

First version, Contains GET list, GET single and PUT for following models:

  • Account (only GET single)
  • Groups
  • Schedule
  • Thermostat

The OpenAPI also introduces 3 EnergyLog endpoints to request energy data for Day, Week and Month basis.

Burst and Rate limits


Burst and rate limits have been implemented to avoid overuse by 3rd party applications. This has been implemented to stop a single client from being able to reduce the quality of service for the rest of the clients, whether it is by accident or on purpose.

Burst and rate limits definition

  • Rate limits
    • The overall "reasonable" allowed rate of calls to the API over a longer period. Usually defined in days and months. Eg. 250.000 in a month.
  • Burst limits
    • The limit of allowed request in a short timeframe, usually defined in seconds or minutes.


Visual representation of burst and rate limits

Current limits

These limits are defined as a per user & per client basis. Which means a single user combined with a specific client id, has these specific limits. That means if a client ids user hits the limit, he is blocked out for the rest of that period, but it does not affect the other users of that client id.

Per second 50
Per 30 minutes 750
Per 12 hours 20,000
Per 7 days 250,000

Http Responses:

When the rate limits are hit, the nVent Nuheat OpenAPI will return HttpCode 429 - Too many requests.
If you hit the limit the response will be:

    Status Code: 429
    Retry-After: 58
    Content: API calls quota exceeded! maximum admitted 2 per 1m.

If the request doesn't get rate limited then the longest period defined in the rules is used to compose the X-Rate-Limit headers, these headers are injected in the response:

    X-Rate-Limit-Limit: the rate limit period (eg. 1m, 12h, 1d)
    X-Rate-Limit-Remaining: number of request remaining
    X-Rate-Limit-Reset: UTC date time (ISO 8601) when the limits resets

A client can parse the X-Rate-Limit-Reset like this:

    DateTime resetDate = DateTime.ParseExact(resetHeader, "o", DateTimeFormatInfo.InvariantInfo);

Validation


A thermostat has two operating modes; Auto and Manual. In Auto mode, the thermostat uses its schedule to adjust the temperature during the day. When the thermostat is set to Operating Mode Manual, the thermostats Schedule and ScheduleMode functionality is disabled, and only the SetPointTemp can be changed. The Thermostat Updates from the API when in Manual mode function as usual, the ScheduleMode and HoldSetPointDateTime is ignored in this mode.
In this section we will cover how to use the different modes, and what input you should provide to get the expected result.

Thermostat Modes

Auto operation has 3 modes you can set the thermostat to:

  • Auto
  • Hold
  • Permanent Hold

Mode: Auto

When using ScheduleMode:Auto the thermostat will use the schedule to define the temperature it should be set to.
In ScheduleMode:Auto you do not have to set the SetPointTemp or HoldSetPointDateTime. Since it does not use any of thise values it will ignore any input from them.
Example:
        {
        "serialNumber": "00000000",
        "setPointTemp": 0,
        "scheduleMode": 1,
        "holdSetPointDateTime": ""
        }
    

Mode: Hold

When using ScheduleMode:Hold, you temporarily set the temperature so it doesn't follow the current schedule.
In this mode you have to set the SetPointTemp or it will try to use the last used value it had in this mode. If the HoldSetPointDateTime is not supplied, it will default to the next schedule event. Once the HoldSetPointDateTime expires it will return to ScheduleMode:Auto.
This functionality can be overwritten by supplying the HoldSetPointDateTime with a specific date and time, as long as it is within the following 23 hours.
Example:
        {
        "serialNumber": "00000000",
        "setPointTemp": 3000,
        "scheduleMode": 2,
        "holdSetPointDateTime": "2018-10-03T19:00:00+00:00"
        }
    

Mode: Permanent Hold

In this mode the temperature is held indefinitely, the thermostat will not revert back to ScheduleMode:Auto on its own.
you can spcify the SetPointTemp to set the thermostats target temperature.
Example:
        {
        "serialNumber": "00000000",
        "setPointTemp": 3000,
        "scheduleMode": 3
        }
    

DateTime format

The required date and time format is ISO-8601 and its based on UTC. All timestamps must be in 24-hour format.

Formats

Date and time
yyyy-MM-ddTHH:mm:ssZ
Date
yyyy-MM-dd
Time
HH:mm

Example:
Date and time:
2018-09-14T07:58:51Z
2018-09-14T09:58:51+02:00

Date:
2017-12-18
2018-09-14

Time:
11:05
23:30


Schedule Rules

When creating ScheduleDayEventModel there are some rules that needs to be followed, the API wont allow you to do otherwise:

  • Each event can't be less than 15 min from the next event.
  • The minute time must be in 15 min interval (15, 30, 45) is valid.
  • You can never deactivate the WAKE event.
  • The SLEEP event, can be placed after midnight, if its before 3 o'clock.
  • You are not allowed to place multiple events of the same type on single day.
  • You are not allowed to place different set of events in the same week-day group. In that case it should placed in a saparete group.

Energy log


The energylog endpoints supplies information about the estimated energy usage for a given period. It tells the amount of minutes the thermostats heating relay has been on, in the given period of that energyUsage-entry.
If the end-user has supplied information in his account about:

  • Kilowatt Rate
  • Heated Floor Area
  • Watt Density
Then the API will also be able to estimate how many KWatt/hour and therefor approximate the $ charge thermostat has spent in the given period.

Energylog data example

{
    "energyUsageType": "Day",
    "energyUsageFrom": "2018-09-25",
    "energyUsageTo": "2018-09-25",
    "mondayIsFirstDay": true,
    "energyUsage": [
        {
            "entry": "23",
            "minutes": 60,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        },
        {
            "entry": "22",
            "minutes": 13,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        },
        {
            "entry": "21",
            "minutes": 0,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        },
        ....
        {
            "entry": "2",
            "minutes": 0,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        },
        {
            "entry": "1",
            "minutes": 0,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        },
        {
            "entry": "0",
            "minutes": 0,
            "energyKWattHour": 0,
            "chargeKWattHour": 0
        }
    ]
}

There are three (3) energylog endpoints, and they are defined as:

Day

Lookup energylog for a single day. It will return the energy spent per individual hour of that day.

  • Input
    • SerialNumber
    • Date of the day you want to lookup energylog for.
  • Output
    • Returns a list of entries for each hour of the day.

Week

Lookup energylog for a given week. It will return the energy spent per individual day of that week.

  • Input
    • SerialNumber
    • Date in the week you want to lookup energylog for.
  • Output
    • Returns a list of entries for each day in the week.

Month

Lookup energylog for a given year. It will return the energy spent per individual month of that year.

  • Input
    • SerialNumber
    • The year you want to lookup energylog for.
  • Output
    • Returns a list of entries for each month of that year.

Change Notifications


Change notifications functionality was implemented utilizing SignalR technology and should be used for minimising an amount of requests to OpenAPI. Currently we support following notification types:

typeid type id
1 UserAccount UserAccount id
2 Thermostat Thermostat Serialnumber
3 Schedule Thermostat Serialnumber
4 Group Group id

Client side for handling notifications is technology agnostic, and some basic examples for  creating SignalR clients can be found here.

Also need to remember that for authorization it is using OAuth2 and OpenID-Connect in the same way as OpenAPI.

Notification data example

    [{"type":3,"id":"223414","timeStamp":"2018-10-04T11:51:27Z"}, {"type":2,"id":"223414","timeStamp":"2018-10-04T11:52:27Z"}]

Code example

The following plain JS/jQuery code sample shows how to create a simple SignalR client, establish connection and subscribe/unsubscripted for certain notification types.  And for authorization it uses oidc-client-js library.

    var oidcConfig = {
    authority: authorityUrl, // OAuth2 authority url.
    client_id: "js", // client id that will be used for authorization.
    redirect_uri: redirectUrl, //Redirect url, should be matched with one defined for the specified client.
    response_type: "id_token token", //Authorization response type
    scope: "openid profile openapi", //Authorization scope
    automaticSilentRenew: true,
    filterProtocolClaims: true, nonce: "N" + Math.random() + "" + Date.now(),
    loadUserInfo: true
    };

    var manager = new Oidc.UserManager(oidcConfig)

    var token;
    manager.signinRedirectCallback().then(function (user) {
        console.log("signed in", user);
        token = user.access_token;
    }).catch(function (err) {
        console.log(err);
    });

    //Builds SignalR connection. SignalR connection hub is called  - "notificationsHost".
    //So full connection url should always be "baseUrl/notificationsHost".

    var connection = new signalR.HubConnectionBuilder().withUrl(baseUrl/notificationsHost+ "?token=" + token).build();

    //Start new connection.

    connection.start().then(() => {
        console.log('Connection started!');
    })
    .catch(err => console.error(err.toString()));
    });

    //Close connection.
    //If notification tracking is not needed anymore then connection should be closed, and it's safe to close connection without unsubscribing from what is currently tracking. 

    connection.stop()
    .then(() => {
        console.log('Connection stopped!');
    })
    .catch(err => console.error(err.toString()));
    });

    //Subscribe for notifications after connections starts.

    var notificationTypes = ["1","2","3","4"]  //Subscribe for all kind of notifications.

    connection
    .invoke("Subscribe", notificationTypes).then(() => {
        console.log('Subscribed for notifications');
    })
    .catch(err => console.error(err.toString()));
    });

    //Unsubscribe from notifications. Please remember that amount of "unsubscribe" calls should be equal to amount of "subscribe" calls

    connection
    .invoke("Unsubscribe", notificationTypes).then(() => {
        console.log('Unsubscribed from notifications');
    })
    .catch(err => console.error(err.toString()));
    });

    //Handle notifications. The only callback that can be invoked on the client side is called - "Notify".

    connection.on("Notify", (value) => {
        traceNotification(value);
    });

    function traceNotification(notificationList) {
        notificationList.forEach(function (notification) {
            var notificationType = "";
            switch (notification.type) {
            case 0:
                notificationType = "UserAccount";
                break;
            case 1:
                notificationType = "UserAccount";
                break;
            case 2:
                notificationType = "Thermostat";
                break;
            case 3:
                notificationType = "Schedule";
                break;
            case 4:
                notificationType = "Group";
            break;
        }
        var traceMessage =
        notificationType + ' notification for item ' + notification.id + " at " + notification.timeStamp;
        console.log(traceMessage);
        });
    }