Object Storage Service:Authorize access (Android SDK)

Manually update the token

Call updateCredentialProvider() before the token expires:

oss.updateCredentialProvider(new OSSStsTokenCredentialProvider(
    "StsToken.AccessKeyId",
    "StsToken.SecretKeyId",
    "StsToken.SecurityToken"
));

The following example checks whether the token is within 5 minutes of expiration and refreshes it:

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
Date date = sdf.parse("<StsToken.Expiration>");
long expiration = date.getTime() / 1000;

// Refresh if expiring within 5 minutes
if (DateUtil.getFixedSkewedTimeMillis() / 1000 > expiration - 5 * 60) {
    oss.updateCredentialProvider(new OSSStsTokenCredentialProvider(
        "StsToken.AccessKeyId",
        "StsToken.SecretKeyId",
        "StsToken.SecurityToken"
    ));
}

Automatically update the token

Implement OSSFederationCredentialProvider so the SDK fetches a new federation token whenever the current one is about to expire:

String endpoint = "http://oss-cn-hangzhou.aliyuncs.com";

OSSCredentialProvider credentialProvider = new OSSFederationCredentialProvider() {

    @Override
    public OSSFederationToken getFederationToken() {
        // Fetch a new token from your server.
        // Return null if the fetch fails.
        OSSFederationToken token;
        // ... fetch token from your server ...
        return token;
    }
};

OSS oss = new OSSClient(getApplicationContext(), endpoint, credentialProvider);

If you already have the STS token fields from another source, return them directly in the callback. In this case, you must handle token refresh yourself and call updateCredentialProvider() on the OSSClient instance after each refresh.

Example: fetch a federation token from your server

If your server at http://localhost:8080/distribute-token.json returns the following response:

{
    "StatusCode": 200,
    "AccessKeyId": "STS.iA645eTOXEqP3cg3****",
    "AccessKeySecret": "rV3VQrpFQ4BsyHSAvi5NVLpPIVffDJv4LojU****",
    "Expiration": "2015-11-03T09:52:59Z",
    "SecurityToken": "CAES7QIIARKAAZPlqaN9ILiQZPS+JDkS/GSZN45RLx4YS/p3OgaUC+oJl3XSlbJ7StKpQ****"
}

Implement OSSFederationCredentialProvider as follows:

OSSCredentialProvider credentialProvider = new OSSFederationCredentialProvider() {

    @Override
    public OSSFederationToken getFederationToken() {
        try {
            URL stsUrl = new URL("http://localhost:8080/distribute-token.json");
            HttpURLConnection conn = (HttpURLConnection) stsUrl.openConnection();
            InputStream input = conn.getInputStream();
            String jsonText = IOUtils.readStreamAsString(input, OSSConstants.DEFAULT_CHARSET_NAME);
            JSONObject jsonObjs = new JSONObject(jsonText);
            String ak = jsonObjs.getString("AccessKeyId");
            String sk = jsonObjs.getString("AccessKeySecret");
            String token = jsonObjs.getString("SecurityToken");
            String expiration = jsonObjs.getString("Expiration");
            return new OSSFederationToken(ak, sk, token, expiration);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
};