MediaKeys: getStatusForPolicy() method

policy Optional

An object with the following optional properties:

minHdcpVersion Optional

A string indicating the semantic version of the minimum HDCP version to check for usability, such as 1.0, 1.4, 2.2, 2.3.

A Promise that resolves with a string indicating whether the key can be used for decryption given the specified policy.

The string can have one of the following values:

usable

The key is currently usable for decryption.

expired

The key is no longer usable for decryption because its expiration time has passed.

released

The key has been released and is no longer available to the CDM. However information about the key is available, such as a record of license destruction.

output-restricted

There are output restrictions associated with the key based on the specified policy. Media data decrypted with this key may be blocked from presentation. The status indicates that the connection between the source and output (for example, your computer and an external display), is not trusted. This might indicate that there are HDCP version mismatches between the source, intermediate devices, and output, or that intermediate connecting devices such as HDMI cables or video splitters are damaged or non-compliant. An application might opt to use a higher HDCP version, content that does not require such a high version. You should also check that intermediate devices and cables support HDCP, are connected firmly, and are not damaged.

output-downscaled

There are output restrictions associated with the key based on the specified policy, however these restrictions might be relaxed if the content is played at a lower quality. If this value is returned an application might play the content at a lower resolution, or it could choose to use a higher HDCP version, or use other content that does not require such a high HDCP version.

usable-in-future

The key will become usable for decryption in future, once its start time is reached.

status-pending

The status of the key is not yet known and is being determined.

internal-error

The key is not currently usable for decryption because of an error in the CDM. The application can't do anything to handle this case.

TypeError

The policy has no defined properties (policy restrictions), or a property key is not valid.

NotSupportedError

The CDM cannot determine the status for any or all of the policy restrictions.

This example checks if keys are usable for decrypting a particular video format when using a minimum HDCP version of 2.2.

HTML

<pre id="log"></pre>

#log {
  height: 100px;
  overflow: scroll;
  padding: 0.5rem;
  border: 1px solid black;
}

JavaScript

const logElement = document.querySelector("#log");
function log(text) {
  logElement.innerText = `${logElement.innerText}${text}\n`;
  logElement.scrollTop = logElement.scrollHeight;
}

const config = [
  {
    videoCapabilities: [
      {
        contentType: 'video/mp4; codecs="avc1.640028"',
        encryptionScheme: "cenc",
        robustness: "SW_SECURE_DECODE", // Widevine L3
      },
    ],
  },
];

getMediaStatus(config);

async function getMediaStatus(config) {
  try {
    const mediaKeySystemAccess = await navigator.requestMediaKeySystemAccess(
      "com.widevine.alpha",
      config,
    );
    const mediaKeys = await mediaKeySystemAccess.createMediaKeys();
    const mediaStatus = await mediaKeys.getStatusForPolicy({
      minHdcpVersion: "2.2",
    });
    log(mediaStatus);

    // Get the content or fallback to an alternative if the
    // keys are not usuable
    if (mediaStatus === "usable") {
      console.log("HDCP 2.2 can be enforced.");
      // Fetch the high resolution protected content
    } else {
      log("HDCP 2.2 cannot be enforced");
      // Fallback other content, get license, etc.
    }
  } catch (error) {
    log(error);
  }
}

Results

• MediaKeyStatusMap.get()