Add rollback snapshot purging functionality

cerndb-sw-zkpolicy.spec

@@ -101,6 +101,9 @@ rm -rf /var/log/zkpolicy
 %postun -p /bin/sh
 
 %changelog
+* Tue Oct 6 2020 Christos Arvanitis <[email protected]> 1.0.1-18
+- Add rollback snapshot purge feature
+
 * Fri Jul 18 2020 Christos Arvanitis <[email protected]> 1.0.1-8
 - Add MIT License
 

zkPolicy/pom.xml

@@ -13,7 +13,7 @@ or submit itself to any jurisdiction.
   <modelVersion>4.0.0</modelVersion>
   <groupId>ch.cern</groupId>
   <artifactId>cerndb-sw-zkpolicy</artifactId>
-  <version>1.0.1-17</version>
+  <version>1.0.1-18</version>
   <name>${project.groupId}:${project.artifactId}</name>
   <description>zkpolicy - ZooKeeper Policy Auditing Tool</description>
   <url>https://github.com/cerndb/zkpolicy</url>

zkPolicy/src/main/java/ch/cern/ZKPolicyCli.java

@@ -25,7 +25,7 @@
 
 @Command(name = "zkpolicy", description = ZkPolicy.DESCRIPTION, versionProvider = ZKPolicyCli.PropertiesVersionProvider.class, subcommands = {
     ZKQueryCli.class, ZKExportCli.class, ZKTreeCli.class, ZKEnforceCli.class, ZKAuditCli.class, ZKCheckCli.class,
-    ZKRollbackCli.class, HelpCommand.class }, mixinStandardHelpOptions = true)
+    ZKRollbackCli.class, ZKPurgeRollbackCli.class, HelpCommand.class }, mixinStandardHelpOptions = true)
 /**
  * Class that handles CLI arguments for the tool.
  */

zkPolicy/src/main/java/ch/cern/ZKPolicyDefs.java

@@ -137,6 +137,13 @@ static class Rollback {
       static final String DESCRIPTION = "Rollback ACLs to pre enforce state";
       static final String INPUT_STATE_DESCRIPTION = "File with ZooKeeper tree state before enforcing";
     }
+
+    static class PurgeRollback {
+      static final String DESCRIPTION = "Purge rollback snapshots, retaining a user defined number";
+      static final String RETAIN_CNT_DESCRIPTION = "Number of rollback snapshots to retain after purging";
+      static final String ROLLBACK_DIR_DESCRIPTION = "Rollback snapshots directory";
+      static final String ROLLBACK_DIR_DEFAULT = "/opt/zkpolicy/rollback";
+    }
   }
 
   static class Queries {

zkPolicy/src/main/java/ch/cern/ZKPurgeRollback.java

@@ -0,0 +1,71 @@
+/*
+* Copyright © 2020, CERN
+* This software is distributed under the terms of the MIT Licence,
+* copied verbatim in the file 'LICENSE'. In applying this licence,
+* CERN does not waive the privileges and immunities
+* granted to it by virtue of its status as an Intergovernmental Organization
+* or submit itself to any jurisdiction.
+*/
+package ch.cern;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.io.IOException;
+import java.util.Arrays;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import lombok.AccessLevel;
+
+
+/**
+ * Purge rollback snapshots.
+ */
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor(access = AccessLevel.PROTECTED)
+public class ZKPurgeRollback {
+  private static Logger logger = LogManager.getLogger(ZKPurgeRollback.class);
+
+  private File rollbackDir;
+  /**
+   * Purge rollback snapshots retaining retainCount number of snapshots.
+   * 
+   * @param retainCount Number of snapshots to retain
+   * @throws IOException
+   */
+  public void purgeRollback(Integer retainCount) throws IOException {
+    // Sort files lexicographically
+    final File[] files = rollbackDir.listFiles(new RollbackFilenameFilter());
+
+    if (files != null) {
+      Arrays.sort(files);
+      Integer totalSnapshotNum = files.length;
+      Integer cnt = 0;
+      for (File rollbackFile : files) {
+        if (totalSnapshotNum - cnt > retainCount) {
+          logger.info("Purging: " + rollbackFile.getPath());
+          if (!rollbackFile.delete()) {
+            logger.error("Failed to delete " + rollbackFile.getPath());
+            throw new IOException("Failed to delete " + rollbackFile.getPath());
+          }
+        } else {
+          break;
+        }
+        cnt = cnt + 1;
+      }
+    }
+  }
+
+  static class RollbackFilenameFilter implements FilenameFilter {
+    @Override
+    public boolean accept(final File dir, final String name) {
+      return name.matches("^ROLLBACK_STATE.*\\.yml");
+    }
+  }
+
+}

zkPolicy/src/main/java/ch/cern/ZKPurgeRollbackCli.java

@@ -0,0 +1,41 @@
+/*
+* Copyright © 2020, CERN
+* This software is distributed under the terms of the MIT Licence,
+* copied verbatim in the file 'LICENSE'. In applying this licence,
+* CERN does not waive the privileges and immunities
+* granted to it by virtue of its status as an Intergovernmental Organization
+* or submit itself to any jurisdiction.
+*/
+package ch.cern;
+
+import picocli.CommandLine.Command;
+import picocli.CommandLine.Option;
+import java.io.File;
+import java.io.IOException;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import ch.cern.ZKPolicyDefs.Cli.PurgeRollback;
+
+@Command(name = "purge-rollback", aliases = {
+    "p" }, description = PurgeRollback.DESCRIPTION, helpCommand = true, mixinStandardHelpOptions = true)
+public class ZKPurgeRollbackCli implements Runnable {
+  private static Logger logger = LogManager.getLogger(ZKPurgeRollbackCli.class);
+
+  @Option(names = { "-r", "--retain-count" }, required = true, description = PurgeRollback.RETAIN_CNT_DESCRIPTION)
+  Integer retainCount;
+
+  @Option(names = { "-d",
+      "--rollback-dir" }, required = false, defaultValue = PurgeRollback.ROLLBACK_DIR_DEFAULT, description = PurgeRollback.ROLLBACK_DIR_DESCRIPTION)
+  File rollbackDir;
+
+  @Override
+  public void run() {
+    ZKPurgeRollback zkPurge = new ZKPurgeRollback(rollbackDir);
+    try {
+      zkPurge.purgeRollback(this.retainCount);
+    } catch (IOException e) {
+      System.out.println(e.toString());
+      logger.error("Exception occurred!", e);
+    }
+  }
+}

zkPolicy/src/test/java/ch/cern/ZKPolicyCliTest.java

@@ -10,7 +10,6 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotEquals;
-import static org.junit.jupiter.api.Assertions.assertNull;
 
 import java.io.ByteArrayOutputStream;
 import java.io.File;

zkPolicy/src/test/java/ch/cern/ZKQueryCliTest.java

@@ -16,9 +16,7 @@
 import java.io.IOException;
 import java.io.PrintStream;
 import java.util.ArrayList;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 
 import org.apache.curator.test.InstanceSpec;
 import org.apache.curator.test.TestingServer;