How to add custom getLicense function?

[AkashYadav00]

Description

videojs-contrib-eme enables us to add custom getLicense function
How to achieve the same using videojs-contrib-dash?

This is my getLicense function:

public async getKeySystems(licenseHeaders, sourceUrl) {

return {
"com.widevine.alpha": {
    supportedConfigurations: [{
                    audioCapabilities: [{
                        initDataTypes: ["cenc"],
                            sessionTypes: ["temporary"],
                        contentType: "audio/mp4; codecs=\"opus\"",
                        robustness: "SW_SECURE_CRYPTO"
                    }]
        }],
        async getLicense(_emeOptions: Object, keyMessage: ArrayBuffer, callback: ICallBackType) {
                    let startTime = window.performance.now();
                    videojs.xhr(
                        {
                            uri: licenseServerUrl,
                            method: HTTP_METHOD_POST,
                            responseType: "arraybuffer",
                            body: JSON.stringify({
                                licenseChallenge: btoa(convertArrayBufferToString(keyMessage)),
                            }),
                            headers: licenseHeaders,
                        },
                        (err, response, responseBody) => {
                         
                            if (err || !response || response.statusCode < 200 || response.statusCode >= 300) {
                                LOG.error(`error`);
                                if (err) {
                                    callback(err);
                                }
                                return;
                            }
                            LOG.info("License fetched successfully");
                          
                            const drmProxyResponse = JSON.parse(
                                convertArrayBufferToString(responseBody)
                            );
                            let key = convertStringToArrayBuffer(atob(drmProxyResponse.license));
                            callback(null, key);
                        }
                    );
                },
}