Define basics for collecting Iceberg metadata for the current snapshot

gobblin-data-management/src/main/java/org/apache/gobblin/data/management/copy/iceberg/IcebergCatalog.java

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+/*
+ * 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.gobblin.data.management.copy.iceberg;
+
+
+/**
+ * Any catalog from which to access {@link IcebergTable}s.
+ */
+public interface IcebergCatalog {
+  IcebergTable openTable(String dbName, String tableName);
+}

gobblin-data-management/src/main/java/org/apache/gobblin/data/management/copy/iceberg/IcebergCatalogFactory.java

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+/*
+ * 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.gobblin.data.management.copy.iceberg;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.iceberg.hive.HiveCatalogs;
+
+
+/**
+ * Provides an {@link IcebergCatalog}.
+ */
+public class IcebergCatalogFactory {
+  public static IcebergCatalog create(Configuration configuration) {
+    return new IcebergHiveCatalog(HiveCatalogs.loadCatalog(configuration));
+  }
+}

gobblin-data-management/src/main/java/org/apache/gobblin/data/management/copy/iceberg/IcebergHiveCatalog.java

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+/*
+ * 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.gobblin.data.management.copy.iceberg;
+
+import lombok.AllArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+import org.apache.iceberg.catalog.TableIdentifier;
+import org.apache.iceberg.hive.HiveCatalog;
+
+
+/**
+ * Hive-Metastore-based {@link IcebergCatalog}.
+ */
+@Slf4j
+@AllArgsConstructor
+public class IcebergHiveCatalog implements IcebergCatalog {
+  // NOTE: specifically necessitates `HiveCatalog`, as `BaseMetastoreCatalog.newTableOps` is `protected`!
+  private final HiveCatalog hc;
+
+  @Override
+  public IcebergTable openTable(String dbName, String tableName) {
+    return new IcebergTable(hc.newTableOps(TableIdentifier.of(dbName, tableName)));
+  }
+}

gobblin-data-management/src/main/java/org/apache/gobblin/data/management/copy/iceberg/IcebergSnapshotInfo.java

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+/*
+ * 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.gobblin.data.management.copy.iceberg;
+
+import java.time.Instant;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import lombok.Data;
+
+import com.google.common.collect.Lists;
+
+
+/**
+ * Information about the metadata file and data file paths of a single Iceberg Snapshot.
+ */
+@Data
+public class IcebergSnapshotInfo {
+
+  @Data
+  public static class ManifestFileInfo {
+    private final String manifestFilePath;
+    private final List<String> listedFilePaths;
+  }
+
+  private final Long snapshotId;
+  private final Instant timestamp;
+  private final String metadataPath;
+  private final String manifestListPath;
+  private final List<ManifestFileInfo> manifestFiles;
+
+  public List<String> getManifestFilePaths() {
+    return manifestFiles.stream().map(ManifestFileInfo::getManifestFilePath).collect(Collectors.toList());
+  }
+
+  public List<String> getAllDataFilePaths() {
+    return manifestFiles.stream().map(ManifestFileInfo::getListedFilePaths).flatMap(List::stream).collect(Collectors.toList());
+  }
+
+  public List<String> getAllPaths() {
+    List<String> result = Lists.newArrayList(metadataPath, manifestListPath);
+    result.addAll(getManifestFilePaths());
+    result.addAll(getAllDataFilePaths());
+    return result;
+  }
+}

gobblin-data-management/src/main/java/org/apache/gobblin/data/management/copy/iceberg/IcebergTable.java

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+/*
+ * 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.gobblin.data.management.copy.iceberg;
+
+import java.io.IOException;
+import java.time.Instant;
+import java.util.List;
+
+import lombok.AllArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+
+import org.apache.iceberg.ManifestFile;
+import org.apache.iceberg.ManifestFiles;
+import org.apache.iceberg.Snapshot;
+import org.apache.iceberg.TableMetadata;
+import org.apache.iceberg.TableOperations;
+import org.apache.iceberg.io.CloseableIterable;
+import org.apache.iceberg.io.FileIO;
+
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.Lists;
+
+import static org.apache.gobblin.data.management.copy.iceberg.IcebergSnapshotInfo.ManifestFileInfo;
+
+
+/**
+ * Exposes metadata information for a single Iceberg table.
+ */
+@Slf4j
+@AllArgsConstructor
+public class IcebergTable {
+  private final TableOperations tableOps;
+
+  public IcebergSnapshotInfo getCurrentSnapshotInfo() throws IOException {
+    TableMetadata current = tableOps.current();
+    Snapshot snapshot = current.currentSnapshot();
+    List<ManifestFile> manifests = snapshot.allManifests();
+    return new IcebergSnapshotInfo(
+        snapshot.snapshotId(),
+        Instant.ofEpochMilli(snapshot.timestampMillis()),
+        current.metadataFileLocation(),
+        snapshot.manifestListLocation(),
+        // NOTE: unable to `.stream().map(m -> calcManifestFileInfo(m, tableOps.io()))` due to checked exception
+        calcAllManifestFileInfo(manifests, tableOps.io())
+      );
+  }
+
+  @VisibleForTesting
+  static List<ManifestFileInfo> calcAllManifestFileInfo(List<ManifestFile> manifests, FileIO io) throws IOException {
+    List<ManifestFileInfo> result = Lists.newArrayList();
+    for (ManifestFile manifest : manifests) {
+      result.add(calcManifestFileInfo(manifest, io));
+    }
+    return result;
+  }
+
+  @VisibleForTesting
+  static IcebergSnapshotInfo.ManifestFileInfo calcManifestFileInfo(ManifestFile manifest, FileIO io) throws IOException {
+    return new ManifestFileInfo(manifest.path(), discoverDataFilePaths(manifest, io));
+  }
+
+  @VisibleForTesting
+  static List<String> discoverDataFilePaths(ManifestFile manifest, FileIO io) throws IOException {
+    CloseableIterable<String> manifestPathsIterable = ManifestFiles.readPaths(manifest, io);
+    try {
+      return Lists.newArrayList(manifestPathsIterable);
+    } finally {
+      manifestPathsIterable.close();
+    }
+  }
+}