Withings Binding

Documentation of the Withings binding Bundle.

Introduction

The Withings Binding allows to synchronize data from the official Withings API to items. The following body measure types are supported: diastolic blood pressure, fat free mass, fat mass weight, fat ratio, heart pulse, height, systolic blood pressure, weight.

For installation of the binding, please see Wiki page Bindings.

Setup

To access Withings data the user needs to authenticate via an OAuth 1.0 flow. The binding implements the flow through the command line interface. The first time the binding is started, it prints the following messages to the console:

#########################################################################################
# Withings Binding needs authentication.
# Execute 'withings:startAuthentication "<accountId>"' on OSGi console.
#########################################################################################

In order to start the authentication process the user needs to execute withings:startAuthentication <accountId> on the OSGi console whereas accountId is an arbitrary key also used in the openhab.cfg in order to differentiate between the different credentials per withings account. The binding will print the following lines to the console

#########################################################################################
# Withings Binding Setup: 
# 1. Open URL 'http://<auth-url>//' in your webbrowser
# 2. Login, choose your user and allow openHAB to access your Withings data
# 3. Execute 'withings:finishAuthentication "<accountId>" "<verifier>" "<user-id>"' on OSGi console
#########################################################################################

So the user needs to open the shown url in a web browser, login with his withings credentials, confirm that openHAB is allowed to access his data and at the end he is redirected to a page on github. There the user finds the command withings:finishAuthentication "<accountId>" "<verifier>" "<user-id>" with filled parameters that is needed to finish the authentication.

The binding stores the OAuth tokens, so that the user does not need to login again. From this point the binding is successfully configured.

Item Binding Configuration

To bind a measure value to an item the measure type has to be defined in the generic binding config. Withings data can be bound to NumberItems only. The syntax for a Withings binding is withings="<measure type>" The following table shows the measure types and units, that are supported by the binding:

Measure type	Binding Config	Unit
Weight	weight	kg
Height	height	meter
Fat Free Mass	fat_free_mass	kg
Fat Ratio	fat_ratio	%
Fat Mass Weight	fat_mass_weight	kg
Diastolic Blood Pressure	diastolic_blood_pressure	mmHg
Systolic Blood Pressure	systolic_blood_pressure	mmHg
Heart Pulse	heart_pulse	bpm

The following snippet shows some sample bindings:

Number Weight     "Weight  [%.1f kg]"     { withings = "weight" }
Number FatRatio   "FatRatio [%.1f %%]"    { withings = "fat_ratio" }
Number HeartPulse "HeartPulse [%d bpm]"   { withings = "heart_pulse" }

Synchronization

By default the Withings data is requested every 60 minutes. The interval can be configured in the openhab.cfg file. The interval must be specified in ms. The following snippet shows a data refresh interval configuration of 120 minutes:

withings:refresh=7200000 

Advanced OAuth Configuration

The Withings Binding uses a default application registration to request an OAuth token. The application belongs to the binding developer. If the user wants to use his own application, the binding can be configured to use another OAuth consumer key and consumer secret. Please read the Withings documentation how to register an application (http://oauth.withings.com/en/partner/dashboard). After the application was created, Withings will generate a consumer key and secret. The redirect url must be configured, too. To change the OAuth parameters for the Withings binding the user can specify the following values in the openhab.cfg :

withings-oauth:consumerKey="<your consumer key>"
withings-oauth:consumerSecret="<your consumer secret>"
withings-oauth:redirectUrl="<your redirect url>"

Furthermore: if there were no values stored into openhab.cfg yet the Binding itself saves it's configuration into the file services/withings-oauth.cfg. Since this specific file is only meant to configure withings values no further prefix is needed. An example file look like:

thomas.token=74c0e77021ef5be1ec8dcb4dd88c1xckusadwe92f9541c86799dcbbfcb8fc8b236
thomas.tokensecret=25f1098209xns511711b3287288f90740ff45532cef91658c5043db0b0e0c851c
...
peter.token=74c0e77021ef5be1ec8dcb4dd88c1xckusadwe92f9541c86799dcbbfcb8fc8b236
peter.tokensecret=25f1098209xns511711b3287288f90740ff45532cef91658c5043db0b0e0c851c

Multiple accounts

If one own multiple withings accounts these accounts must be configured specifically. In addition to the above mentioned openhab.cfg configuration, an accountId can be specified.

withings-oauth:thomas.token=74c0e77021ef5be1ec8dcb4dd88c1xckusadwe92f9541c86799dcbbfcb8fc8b236
withings-oauth:thomas.tokensecret=25f1098209xns511711b3287288f90740ff45532cef91658c5043db0b0e0c851c
...
withings-oauth:peter.token=74c0e77021ef5be1ec8dcb4dd88c1xckusadwe92f9541c86799dcbbfcb8fc8b236
withings-oauth:peter.tokensecret=25f1098209xns511711b3287288f90740ff45532cef91658c5043db0b0e0c851c