creste commented on code in PR #5953: URL: https://github.com/apache/hadoop/pull/5953#discussion_r1453652596
########## hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azurebfs/oauth2/WorkloadIdentityTokenProvider.java: ########## @@ -0,0 +1,108 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package org.apache.hadoop.fs.azurebfs.oauth2; + +import java.io.File; +import java.io.IOException; + +import org.apache.hadoop.thirdparty.com.google.common.base.Strings; +import org.apache.hadoop.util.Preconditions; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import org.apache.commons.io.FileUtils; + + +/** + * Provides tokens based on Azure AD Workload Identity. + */ +public class WorkloadIdentityTokenProvider extends AccessTokenProvider { + + private static final String OAUTH2_TOKEN_PATH = "/oauth2/v2.0/token"; + private final String authEndpoint; + + private final String clientId; + + private final String tokenFile; + + private long tokenFetchTime = -1; + + private static final long ONE_HOUR = 3600 * 1000; + + private static final Logger LOG = LoggerFactory.getLogger(AccessTokenProvider.class); + + public WorkloadIdentityTokenProvider(final String authority, final String tenantId, + final String clientId, final String tokenFile) { + Preconditions.checkNotNull(authority, "authority"); + Preconditions.checkNotNull(tenantId, "tenantId"); + Preconditions.checkNotNull(clientId, "clientId"); + Preconditions.checkNotNull(tokenFile, "tokenFile"); + + this.authEndpoint = authority + tenantId + OAUTH2_TOKEN_PATH; + this.clientId = clientId; + this.tokenFile = tokenFile; + } + + @Override + protected AzureADToken refreshToken() throws IOException { + LOG.debug("AADToken: refreshing token from JWT Assertion"); + String clientAssertion = getClientAssertion(tokenFile); + AzureADToken token = AzureADAuthenticator + .getTokenUsingJWTAssertion(authEndpoint, clientId, clientAssertion); + tokenFetchTime = System.currentTimeMillis(); + return token; + } + + /** + * Checks if the token is about to expire as per base expiry logic. + * Otherwise try to expire every 1 hour. + * + * @return true if the token is expiring in next 1 hour or if a token has + * never been fetched + */ + @Override + protected boolean isTokenAboutToExpire() { + if (tokenFetchTime == -1 || super.isTokenAboutToExpire()) { + return true; + } + + boolean expiring = false; + long elapsedTimeSinceLastTokenRefreshInMillis = + System.currentTimeMillis() - tokenFetchTime; + // In case token is not refreshed for 1 hr or any clock skew issues, + // refresh token. + expiring = elapsedTimeSinceLastTokenRefreshInMillis >= ONE_HOUR + || elapsedTimeSinceLastTokenRefreshInMillis < 0; + if (expiring) { + LOG.debug("JWTToken: token renewing. Time elapsed since last token fetch:" + + " {} milliseconds", elapsedTimeSinceLastTokenRefreshInMillis); + } + + return expiring; + } + + private static String getClientAssertion(String tokenFile) Review Comment: >there is some process on the azure vm which refreshes this file? Yes. >please cite the reference I added the [citation](https://azure.github.io/azure-workload-identity/docs/faq.html#does-workload-identity-work-in-disconnected-environments) to the javadoc for `getClientAssertion`. >As, it is important that the tokenFile is not cached, lets add a test around this as well. The only way I see to verify the token file is not cached is to somehow mock the call to `AzureADAuthenticator.getTokenUsingJWTAssertion()` in `WorkloadIdentityTokenProvider.refreshToken()`, which is problematic. Please see my comments [here](https://github.com/apache/hadoop/pull/5953/files#r1453634534) regarding my thoughts on mocking it. If we can identify a way to mock that code then I can add a unit test to verify the token file is not cached. Otherwise, I don't see how to implement that unit test. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
