Merge pull request #31 from Altinity/catalog-retry-policy

patch: Catalog retry policy

Author: shyiko

ice-rest-catalog/src/main/java/org/apache/iceberg/BaseMetastoreTableOperations.java

@@ -0,0 +1,361 @@
+/*
+ * 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.iceberg;
+
+import java.util.Locale;
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import org.apache.iceberg.encryption.EncryptionManager;
+import org.apache.iceberg.exceptions.AlreadyExistsException;
+import org.apache.iceberg.exceptions.CommitFailedException;
+import org.apache.iceberg.exceptions.NoSuchTableException;
+import org.apache.iceberg.exceptions.NotFoundException;
+import org.apache.iceberg.io.FileIO;
+import org.apache.iceberg.io.LocationProvider;
+import org.apache.iceberg.io.OutputFile;
+import org.apache.iceberg.relocated.com.google.common.base.Objects;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.util.LocationUtil;
+import org.apache.iceberg.util.Tasks;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import software.amazon.awssdk.core.exception.SdkServiceException;
+
+public abstract class BaseMetastoreTableOperations extends BaseMetastoreOperations
+    implements TableOperations {
+  private static final Logger LOG = LoggerFactory.getLogger(BaseMetastoreTableOperations.class);
+
+  public static final String TABLE_TYPE_PROP = "table_type";
+  public static final String ICEBERG_TABLE_TYPE_VALUE = "iceberg";
+  public static final String METADATA_LOCATION_PROP = "metadata_location";
+  public static final String PREVIOUS_METADATA_LOCATION_PROP = "previous_metadata_location";
+
+  private static final String METADATA_FOLDER_NAME = "metadata";
+
+  private TableMetadata currentMetadata = null;
+  private String currentMetadataLocation = null;
+  private boolean shouldRefresh = true;
+  private int version = -1;
+
+  protected BaseMetastoreTableOperations() {}
+
+  /**
+   * The full name of the table used for logging purposes only. For example for HiveTableOperations
+   * it is catalogName + "." + database + "." + table.
+   *
+   * @return The full name
+   */
+  protected abstract String tableName();
+
+  @Override
+  public TableMetadata current() {
+    if (shouldRefresh) {
+      return refresh();
+    }
+    return currentMetadata;
+  }
+
+  public String currentMetadataLocation() {
+    return currentMetadataLocation;
+  }
+
+  public int currentVersion() {
+    return version;
+  }
+
+  @Override
+  public TableMetadata refresh() {
+    boolean currentMetadataWasAvailable = currentMetadata != null;
+    try {
+      doRefresh();
+    } catch (NoSuchTableException e) {
+      if (currentMetadataWasAvailable) {
+        LOG.warn("Could not find the table during refresh, setting current metadata to null", e);
+        shouldRefresh = true;
+      }
+
+      currentMetadata = null;
+      currentMetadataLocation = null;
+      version = -1;
+      throw e;
+    }
+    return current();
+  }
+
+  protected void doRefresh() {
+    throw new UnsupportedOperationException("Not implemented: doRefresh");
+  }
+
+  @Override
+  public void commit(TableMetadata base, TableMetadata metadata) {
+    // if the metadata is already out of date, reject it
+    if (base != current()) {
+      if (base != null) {
+        throw new CommitFailedException("Cannot commit: stale table metadata");
+      } else {
+        // when current is non-null, the table exists. but when base is null, the commit is trying
+        // to create the table
+        throw new AlreadyExistsException("Table already exists: %s", tableName());
+      }
+    }
+    // if the metadata is not changed, return early
+    if (base == metadata) {
+      LOG.info("Nothing to commit.");
+      return;
+    }
+
+    long start = System.currentTimeMillis();
+    doCommit(base, metadata);
+    CatalogUtil.deleteRemovedMetadataFiles(io(), base, metadata);
+    requestRefresh();
+
+    LOG.info(
+        "Successfully committed to table {} in {} ms",
+        tableName(),
+        System.currentTimeMillis() - start);
+  }
+
+  protected void doCommit(TableMetadata base, TableMetadata metadata) {
+    throw new UnsupportedOperationException("Not implemented: doCommit");
+  }
+
+  protected void requestRefresh() {
+    this.shouldRefresh = true;
+  }
+
+  protected void disableRefresh() {
+    this.shouldRefresh = false;
+  }
+
+  protected String writeNewMetadataIfRequired(boolean newTable, TableMetadata metadata) {
+    return newTable && metadata.metadataFileLocation() != null
+        ? metadata.metadataFileLocation()
+        : writeNewMetadata(metadata, currentVersion() + 1);
+  }
+
+  protected String writeNewMetadata(TableMetadata metadata, int newVersion) {
+    String newTableMetadataFilePath = newTableMetadataFilePath(metadata, newVersion);
+    OutputFile newMetadataLocation = io().newOutputFile(newTableMetadataFilePath);
+
+    // write the new metadata
+    // use overwrite to avoid negative caching in S3. this is safe because the metadata location is
+    // always unique because it includes a UUID.
+    TableMetadataParser.overwrite(metadata, newMetadataLocation);
+
+    return newMetadataLocation.location();
+  }
+
+  protected void refreshFromMetadataLocation(String newLocation) {
+    refreshFromMetadataLocation(newLocation, null, 20);
+  }
+
+  protected void refreshFromMetadataLocation(String newLocation, int numRetries) {
+    refreshFromMetadataLocation(newLocation, null, numRetries);
+  }
+
+  protected void refreshFromMetadataLocation(
+      String newLocation, Predicate<Exception> shouldRetry, int numRetries) {
+    refreshFromMetadataLocation(
+        newLocation,
+        shouldRetry,
+        numRetries,
+        metadataLocation -> TableMetadataParser.read(io(), metadataLocation));
+  }
+
+  protected void refreshFromMetadataLocation(
+      String newLocation,
+      Predicate<Exception> shouldRetry,
+      int numRetries,
+      Function<String, TableMetadata> metadataLoader) {
+    // use null-safe equality check because new tables have a null metadata location
+    if (!Objects.equal(currentMetadataLocation, newLocation)) {
+      LOG.info("Refreshing table metadata from new version: {}", newLocation);
+
+      if (shouldRetry == null) {
+        shouldRetry =
+            e ->
+                e instanceof SdkServiceException
+                    && ((SdkServiceException) e).isRetryableException();
+      }
+
+      AtomicReference<TableMetadata> newMetadata = new AtomicReference<>();
+      Tasks.foreach(newLocation)
+          .retry(numRetries)
+          .exponentialBackoff(100, 5000, 600000, 4.0 /* 100, 400, 1600, ... */)
+          .throwFailureWhenFinished()
+          .stopRetryOn(NotFoundException.class) // overridden if shouldRetry is non-null
+          .shouldRetryTest(shouldRetry)
+          .run(metadataLocation -> newMetadata.set(metadataLoader.apply(metadataLocation)));
+
+      String newUUID = newMetadata.get().uuid();
+      if (currentMetadata != null && currentMetadata.uuid() != null && newUUID != null) {
+        Preconditions.checkState(
+            newUUID.equals(currentMetadata.uuid()),
+            "Table UUID does not match: current=%s != refreshed=%s",
+            currentMetadata.uuid(),
+            newUUID);
+      }
+
+      this.currentMetadata = newMetadata.get();
+      this.currentMetadataLocation = newLocation;
+      this.version = parseVersion(newLocation);
+    }
+    this.shouldRefresh = false;
+  }
+
+  private String metadataFileLocation(TableMetadata metadata, String filename) {
+    String metadataLocation = metadata.properties().get(TableProperties.WRITE_METADATA_LOCATION);
+
+    if (metadataLocation != null) {
+      return String.format("%s/%s", LocationUtil.stripTrailingSlash(metadataLocation), filename);
+    } else {
+      return String.format("%s/%s/%s", metadata.location(), METADATA_FOLDER_NAME, filename);
+    }
+  }
+
+  @Override
+  public String metadataFileLocation(String filename) {
+    return metadataFileLocation(current(), filename);
+  }
+
+  @Override
+  public LocationProvider locationProvider() {
+    return LocationProviders.locationsFor(current().location(), current().properties());
+  }
+
+  @Override
+  public TableOperations temp(TableMetadata uncommittedMetadata) {
+    return new TableOperations() {
+      @Override
+      public TableMetadata current() {
+        return uncommittedMetadata;
+      }
+
+      @Override
+      public TableMetadata refresh() {
+        throw new UnsupportedOperationException(
+            "Cannot call refresh on temporary table operations");
+      }
+
+      @Override
+      public void commit(TableMetadata base, TableMetadata metadata) {
+        throw new UnsupportedOperationException("Cannot call commit on temporary table operations");
+      }
+
+      @Override
+      public String metadataFileLocation(String fileName) {
+        return BaseMetastoreTableOperations.this.metadataFileLocation(
+            uncommittedMetadata, fileName);
+      }
+
+      @Override
+      public LocationProvider locationProvider() {
+        return LocationProviders.locationsFor(
+            uncommittedMetadata.location(), uncommittedMetadata.properties());
+      }
+
+      @Override
+      public FileIO io() {
+        return BaseMetastoreTableOperations.this.io();
+      }
+
+      @Override
+      public EncryptionManager encryption() {
+        return BaseMetastoreTableOperations.this.encryption();
+      }
+
+      @Override
+      public long newSnapshotId() {
+        return BaseMetastoreTableOperations.this.newSnapshotId();
+      }
+    };
+  }
+
+  /**
+   * Attempt to load the table and see if any current or past metadata location matches the one we
+   * were attempting to set. This is used as a last resort when we are dealing with exceptions that
+   * may indicate the commit has failed but are not proof that this is the case. Past locations must
+   * also be searched on the chance that a second committer was able to successfully commit on top
+   * of our commit.
+   *
+   * @param newMetadataLocation the path of the new commit file
+   * @param config metadata to use for configuration
+   * @return Commit Status of Success, Failure or Unknown
+   */
+  protected CommitStatus checkCommitStatus(String newMetadataLocation, TableMetadata config) {
+    return CommitStatus.valueOf(
+        checkCommitStatus(
+                tableName(),
+                newMetadataLocation,
+                config.properties(),
+                () -> checkCurrentMetadataLocation(newMetadataLocation))
+            .name());
+  }
+
+  /**
+   * Validate if the new metadata location is the current metadata location or present within
+   * previous metadata files.
+   *
+   * @param newMetadataLocation newly written metadata location
+   * @return true if the new metadata location is the current metadata location or present within
+   *     previous metadata files.
+   */
+  private boolean checkCurrentMetadataLocation(String newMetadataLocation) {
+    TableMetadata metadata = refresh();
+    String currentMetadataFileLocation = metadata.metadataFileLocation();
+    return currentMetadataFileLocation.equals(newMetadataLocation)
+        || metadata.previousFiles().stream()
+            .anyMatch(log -> log.file().equals(newMetadataLocation));
+  }
+
+  private String newTableMetadataFilePath(TableMetadata meta, int newVersion) {
+    String codecName =
+        meta.property(
+            TableProperties.METADATA_COMPRESSION, TableProperties.METADATA_COMPRESSION_DEFAULT);
+    String fileExtension = TableMetadataParser.getFileExtension(codecName);
+    return metadataFileLocation(
+        meta,
+        String.format(Locale.ROOT, "%05d-%s%s", newVersion, UUID.randomUUID(), fileExtension));
+  }
+
+  /**
+   * Parse the version from table metadata file name.
+   *
+   * @param metadataLocation table metadata file location
+   * @return version of the table metadata file in success case and -1 if the version is not
+   *     parsable (as a sign that the metadata is not part of this catalog)
+   */
+  private static int parseVersion(String metadataLocation) {
+    int versionStart = metadataLocation.lastIndexOf('/') + 1; // if '/' isn't found, this will be 0
+    int versionEnd = metadataLocation.indexOf('-', versionStart);
+    if (versionEnd < 0) {
+      // found filesystem table's metadata
+      return -1;
+    }
+
+    try {
+      return Integer.parseInt(metadataLocation.substring(versionStart, versionEnd));
+    } catch (NumberFormatException e) {
+      LOG.warn("Unable to parse version from metadata location: {}", metadataLocation, e);
+      return -1;
+    }
+  }
+}