Android OAuth

OAuth is used to open a web view and get the access token to download the vehicle's Access Certificate. At first the access token
should be requested with getAccessToken() method. Subsequently the refreshAccessToken()
method can be used for token refreshing.

Table of Contents

Getting the instance

Get the OAuth instance.

Declaration

public OAuth getOAuth();

Returns

The OAuth instance

Discussion

OAuth can be accessed from the HMKit object. A device certificate must be set before

Example

    val oauth = HMKit.getInstance().getOAuth();

Methods

Get the Access Token

Declaration

fun getAccessToken(
        activity: Activity,
        appId,
        authUrl,
        clientId,
        redirectScheme,
        tokenUrl,
        startDate: Calendar? = null,
        endDate: Calendar? = null,
        state? = null,
        completionHandler: CompletionHandler)

Parameters

activity

The activity the web view is launched from

appId

The application's identifier

authUrl

The base authentication URI

clientId

The client identifier

redirectScheme

The redirect scheme URI used to redirect back to the app

tokenUrl

The token url where the access token is requested from

startDate

The start date

endDate

The end date

state

The optional state

completionHandler

The completion handler that is invoked with access and refresh tokens or an error

Discussion

Start the access token flow, where a web view is opened for the user to select a vehicle for which an Access Token is downloaded. That access token is returned to the user and can be used to download the vehicle's Access Certificate via HMKit.downloadAccessCertificate

Read More

Example

/*
HMKit initialised.
Called inside an Activity.
*/

val appId = "..."
val authUrl = "..."
val clientID = "..."
val redirectScheme = "..."
val tokenUrl = "..."

HMKit.getInstance().oAuth.getAccessToken(
        this,
        appId,
        authUrl,
        clientID,
        redirectScheme,
        tokenUrl
) { accessToken, errorMessage ->
    if (accessToken != null) {
        // Optional: store the refresh token and expiration data
        this.refreshToken = accessToken.refreshToken
        this.expireDate = (System.currentTimeMillis() / 1000).toInt() + accessToken.expiresIn
        
        // Download the vehicle's Access Certificate
        HMKit.getInstance().downloadAccessCertificate(accessToken.accessToken, object : HMKit.DownloadCallback {
            // response handling
        })
    }
    else {
        // if there is no access token, there is an error
        onError(errorMessage!!)
    }
}

Refresh the Access Token

Declaration

fun refreshAccessToken(
        tokenUrl,
        clientId,
        refreshToken,
        completionHandler: CompletionHandler)

Parameters

tokenUrl

The token url where the access token is requested from

clientId

The client identifier

refreshToken

The Refresh Token

completionHandler

The completion handler that is invoked with access and refresh tokens or an error

Discussion

Refresh the previously aqcuired Access Token, without the need for user interaction in a web view. Use the refreshed Access Token to download an Access Certificate with HMKit.downloadAccessCertificate

Read More

Example

/*
HMKit is initialised.
Called inside an Activity.
*/

val tokenUrl = "..."
val clientId = "..."
val refreshToken = "..." // stored previously from the getAccessToken result

HMKit.getInstance().oAuth.refreshAccessToken(
        this,
        tokenUrl,
        clientId,
        refreshToken
) { accessToken, errorMessage ->
// same response as for the getAccessToken
if (accessToken != null) { }
else { }
}