[server] Add configuration options for multiple remote data directories

fluss-common/src/main/java/org/apache/fluss/config/ConfigOptions.java

@@ -97,7 +97,53 @@ public class ConfigOptions {
                     .noDefaultValue()
                     .withDescription(
                             "The directory used for storing the kv snapshot data files and remote log for log tiered storage "
-                                    + " in a Fluss supported filesystem.");
+                                    + "in a Fluss supported filesystem.");
+
+    public static final ConfigOption<List<String>> REMOTE_DATA_DIRS =
+            key("remote.data.dirs")
+                    .stringType()
+                    .asList()
+                    .defaultValues()
+                    .withDescription(
+                            "The directories used for storing the kv snapshot data files and remote log for log tiered storage "
+                                    + "in a Fluss supported filesystem. "
+                                    + "This should be a comma-separated list of remote URIs. "
+                                    + "If not configured, it defaults to the path specified in `"
+                                    + REMOTE_DATA_DIR.key()
+                                    + "`. Otherwise, one of the paths from this configuration will be used.");
+
+    public static final ConfigOption<RemoteDataDirStrategy> REMOTE_DATA_DIRS_STRATEGY =
+            key("remote.data.dirs.strategy")
+                    .enumType(RemoteDataDirStrategy.class)
+                    .defaultValue(RemoteDataDirStrategy.ROUND_ROBIN)
+                    .withDescription(
+                            String.format(
+                                    "The strategy for selecting the remote data directory from `%s`. "
+                                            + "The candidate strategies are: %s, the default strategy is %s.\n"
+                                            + "%s: this strategy employs a round-robin approach to select one from the available remote directories.\n"
+                                            + "%s: this strategy selects one of the available remote directories based on the weights configured in `remote.data.dirs.weights`.",
+                                    REMOTE_DATA_DIRS.key(),
+                                    Arrays.toString(RemoteDataDirStrategy.values()),
+                                    RemoteDataDirStrategy.ROUND_ROBIN,
+                                    RemoteDataDirStrategy.ROUND_ROBIN,
+                                    RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN));
+
+    public static final ConfigOption<List<Integer>> REMOTE_DATA_DIRS_WEIGHTS =
+            key("remote.data.dirs.weights")
+                    .intType()
+                    .asList()
+                    .defaultValues()
+                    .withDescription(
+                            "The weights of the remote data directories. "
+                                    + "This is a list of weights corresponding to the `"
+                                    + REMOTE_DATA_DIRS.key()
+                                    + "` in the same order. When `"
+                                    + REMOTE_DATA_DIRS_STRATEGY.key()
+                                    + "` is set to `"
+                                    + RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN
+                                    + "`, this must be configured, and its size must be equal to `"
+                                    + REMOTE_DATA_DIRS.key()
+                                    + "`; otherwise, it will be ignored.");
 
     public static final ConfigOption<MemorySize> REMOTE_FS_WRITE_BUFFER_SIZE =
             key("remote.fs.write-buffer-size")
@@ -2066,4 +2112,10 @@ private static class ConfigOptionsHolder {
     public static ConfigOption<?> getConfigOption(String key) {
         return ConfigOptionsHolder.CONFIG_OPTIONS_BY_KEY.get(key);
     }
+
+    /** Remote data dir select strategy for Fluss. */
+    public enum RemoteDataDirStrategy {
+        ROUND_ROBIN,
+        WEIGHTED_ROUND_ROBIN
+    }
 }

fluss-common/src/main/java/org/apache/fluss/config/FlussConfigUtils.java

@@ -19,12 +19,16 @@
 
 import org.apache.fluss.annotation.Internal;
 import org.apache.fluss.annotation.VisibleForTesting;
+import org.apache.fluss.exception.IllegalConfigurationException;
+import org.apache.fluss.fs.FsPath;
+import org.apache.fluss.utils.FlussPaths;
 
 import java.lang.reflect.Field;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 
 /** Utilities of Fluss {@link ConfigOptions}. */
 @Internal
@@ -77,4 +81,109 @@ static Map<String, ConfigOption<?>> extractConfigOptions(String prefix) {
         }
         return options;
     }
+
+    public static void validateCoordinatorConfigs(Configuration conf) {
+        validServerConfigs(conf);
+
+        validMinValue(conf, ConfigOptions.DEFAULT_REPLICATION_FACTOR, 1);
+        validMinValue(conf, ConfigOptions.KV_MAX_RETAINED_SNAPSHOTS, 1);
+        validMinValue(conf, ConfigOptions.SERVER_IO_POOL_SIZE, 1);
+
+        // Validate remote.data.dirs
+        List<String> remoteDataDirs = conf.get(ConfigOptions.REMOTE_DATA_DIRS);
+        for (int i = 0; i < remoteDataDirs.size(); i++) {
+            String remoteDataDir = remoteDataDirs.get(i);
+            try {
+                new FsPath(remoteDataDir);
+            } catch (Exception e) {
+                throw new IllegalConfigurationException(
+                        String.format(
+                                "Invalid remote path for %s at index %d.",
+                                ConfigOptions.REMOTE_DATA_DIRS.key(), i),
+                        e);
+            }
+        }
+
+        // Validate remote.data.dirs.strategy
+        ConfigOptions.RemoteDataDirStrategy remoteDataDirStrategy =
+                conf.get(ConfigOptions.REMOTE_DATA_DIRS_STRATEGY);
+        if (remoteDataDirStrategy == ConfigOptions.RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN) {
+            List<Integer> weights = conf.get(ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS);
+            if (!remoteDataDirs.isEmpty() && !weights.isEmpty()) {
+                if (remoteDataDirs.size() != weights.size()) {
+                    throw new IllegalConfigurationException(
+                            String.format(
+                                    "The size of '%s' (%d) must match the size of '%s' (%d) when using WEIGHTED_ROUND_ROBIN strategy.",
+                                    ConfigOptions.REMOTE_DATA_DIRS.key(),
+                                    remoteDataDirs.size(),
+                                    ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS.key(),
+                                    weights.size()));
+                }
+                // Validate all weights are positive
+                for (int i = 0; i < weights.size(); i++) {
+                    if (weights.get(i) < 0) {
+                        throw new IllegalConfigurationException(
+                                String.format(
+                                        "All weights in '%s' must be no less than 0, but found %d at index %d.",
+                                        ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS.key(),
+                                        weights.get(i),
+                                        i));
+                    }
+                }
+            }
+        }
+    }
+
+    public static void validateTabletConfigs(Configuration conf) {
+        validServerConfigs(conf);
+
+        Optional<Integer> serverId = conf.getOptional(ConfigOptions.TABLET_SERVER_ID);
+        if (!serverId.isPresent()) {
+            throw new IllegalConfigurationException(
+                    String.format("Configuration %s must be set.", ConfigOptions.TABLET_SERVER_ID));
+        }
+        validMinValue(ConfigOptions.TABLET_SERVER_ID, serverId.get(), 0);
+
+        validMinValue(conf, ConfigOptions.BACKGROUND_THREADS, 1);
+
+        if (conf.get(ConfigOptions.LOG_SEGMENT_FILE_SIZE).getBytes() > Integer.MAX_VALUE) {
+            throw new IllegalConfigurationException(
+                    String.format(
+                            "Invalid configuration for %s, it must be less than or equal %d bytes.",
+                            ConfigOptions.LOG_SEGMENT_FILE_SIZE.key(), Integer.MAX_VALUE));
+        }
+    }
+
+    /** Validate common server configs. */
+    private static void validServerConfigs(Configuration conf) {
+        if (conf.get(ConfigOptions.REMOTE_DATA_DIR) == null) {
+            throw new IllegalConfigurationException(
+                    String.format("Configuration %s must be set.", ConfigOptions.REMOTE_DATA_DIR));
+        } else {
+            // Must validate that remote.data.dir is a valid FsPath
+            try {
+                FlussPaths.remoteDataDir(conf);
+            } catch (Exception e) {
+                throw new IllegalConfigurationException(
+                        String.format(
+                                "Invalid configuration for %s.",
+                                ConfigOptions.REMOTE_DATA_DIR.key()),
+                        e);
+            }
+        }
+    }
+
+    private static void validMinValue(
+            Configuration conf, ConfigOption<Integer> option, int minValue) {
+        validMinValue(option, conf.get(option), minValue);
+    }
+
+    private static void validMinValue(ConfigOption<Integer> option, int value, int minValue) {
+        if (value < minValue) {
+            throw new IllegalConfigurationException(
+                    String.format(
+                            "Invalid configuration for %s, it must be greater than or equal %d.",
+                            option.key(), minValue));
+        }
+    }
 }

fluss-common/src/main/java/org/apache/fluss/utils/FlussPaths.java

@@ -409,6 +409,23 @@ public static UUID uuidFromRemoteIndexCacheFileName(String fileName) {
                 fileName.substring(fileName.indexOf('_') + 1, fileName.indexOf('.')));
     }
 
+    // ----------------------------------------------------------------------------------------
+    // Remote Data Paths
+    // ----------------------------------------------------------------------------------------
+
+    /**
+     * Returns the remote root directory path for storing data files.
+     *
+     * <p>The path contract:
+     *
+     * <pre>
+     * {$remote.data.dir}
+     * </pre>
+     */
+    public static FsPath remoteDataDir(Configuration conf) {
+        return new FsPath(conf.get(ConfigOptions.REMOTE_DATA_DIR));
+    }
+
     // ----------------------------------------------------------------------------------------
     // Remote Log Paths
     // ----------------------------------------------------------------------------------------

fluss-common/src/test/java/org/apache/fluss/config/FlussConfigUtilsTest.java

@@ -17,14 +17,20 @@
 
 package org.apache.fluss.config;
 
+import org.apache.fluss.exception.IllegalConfigurationException;
+
 import org.junit.jupiter.api.Test;
 
+import java.util.Arrays;
+import java.util.Collections;
 import java.util.Map;
 
 import static org.apache.fluss.config.FlussConfigUtils.CLIENT_OPTIONS;
 import static org.apache.fluss.config.FlussConfigUtils.TABLE_OPTIONS;
 import static org.apache.fluss.config.FlussConfigUtils.extractConfigOptions;
+import static org.apache.fluss.config.FlussConfigUtils.validateCoordinatorConfigs;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 
 /** Test for {@link FlussConfigUtils}. */
 class FlussConfigUtilsTest {
@@ -49,4 +55,105 @@ void testExtractOptions() {
                 });
         assertThat(clientOptions.size()).isEqualTo(CLIENT_OPTIONS.size());
     }
+
+    @Test
+    void testValidateCoordinatorConfigs() {
+        // Test valid configuration
+        Configuration validConf = new Configuration();
+        validConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        validateCoordinatorConfigs(validConf);
+
+        // Test invalid DEFAULT_REPLICATION_FACTOR
+        Configuration invalidReplicationConf = new Configuration();
+        invalidReplicationConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        invalidReplicationConf.set(ConfigOptions.DEFAULT_REPLICATION_FACTOR, 0);
+        assertThatThrownBy(() -> validateCoordinatorConfigs(invalidReplicationConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.DEFAULT_REPLICATION_FACTOR.key())
+                .hasMessageContaining("must be greater than or equal 1");
+
+        // Test invalid KV_MAX_RETAINED_SNAPSHOTS
+        Configuration invalidSnapshotConf = new Configuration();
+        invalidSnapshotConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        invalidSnapshotConf.set(ConfigOptions.KV_MAX_RETAINED_SNAPSHOTS, 0);
+        assertThatThrownBy(() -> validateCoordinatorConfigs(invalidSnapshotConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.KV_MAX_RETAINED_SNAPSHOTS.key())
+                .hasMessageContaining("must be greater than or equal 1");
+
+        // Test invalid SERVER_IO_POOL_SIZE
+        Configuration invalidIoPoolConf = new Configuration();
+        invalidIoPoolConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        invalidIoPoolConf.set(ConfigOptions.SERVER_IO_POOL_SIZE, 0);
+        assertThatThrownBy(() -> validateCoordinatorConfigs(invalidIoPoolConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.SERVER_IO_POOL_SIZE.key())
+                .hasMessageContaining("must be greater than or equal 1");
+
+        // Test REMOTE_DATA_DIR not set
+        Configuration noRemoteDirConf = new Configuration();
+        assertThatThrownBy(() -> validateCoordinatorConfigs(noRemoteDirConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIR.key())
+                .hasMessageContaining("must be set");
+
+        // Test invalid REMOTE_DATA_DIR
+        Configuration invalidRemoteDirConf = new Configuration();
+        invalidRemoteDirConf.set(ConfigOptions.REMOTE_DATA_DIR, "123://invalid.com");
+        assertThatThrownBy(() -> validateCoordinatorConfigs(invalidRemoteDirConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIR.key())
+                .hasMessageContaining("Invalid configuration for remote.data.dir");
+
+        // Test REMOTE_DATA_DIRS contains invalid path
+        Configuration invalidRemoteDirsConf = new Configuration();
+        invalidRemoteDirsConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        invalidRemoteDirsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS, Arrays.asList("s3://bucket1", "123://invalid.com"));
+        assertThatThrownBy(() -> validateCoordinatorConfigs(invalidRemoteDirsConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIRS.key())
+                .hasMessageContaining("Invalid remote path for remote.data.dirs");
+
+        // Test WEIGHTED_ROUND_ROBIN with mismatched sizes
+        Configuration mismatchedWeightsConf = new Configuration();
+        mismatchedWeightsConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        mismatchedWeightsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS_STRATEGY,
+                ConfigOptions.RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN);
+        mismatchedWeightsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS, Arrays.asList("s3://bucket1", "s3://bucket2"));
+        mismatchedWeightsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS, Collections.singletonList(1));
+        assertThatThrownBy(() -> validateCoordinatorConfigs(mismatchedWeightsConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS.key())
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIRS.key());
+
+        // Test WEIGHTED_ROUND_ROBIN with matched sizes
+        Configuration matchedWeightsConf = new Configuration();
+        matchedWeightsConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        matchedWeightsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS_STRATEGY,
+                ConfigOptions.RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN);
+        matchedWeightsConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS, Arrays.asList("s3://bucket1", "s3://bucket2"));
+        matchedWeightsConf.set(ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS, Arrays.asList(1, 2));
+        validateCoordinatorConfigs(matchedWeightsConf);
+
+        // Test negative weight
+        Configuration negativeWeightConf = new Configuration();
+        negativeWeightConf.set(ConfigOptions.REMOTE_DATA_DIR, "s3://bucket/path");
+        negativeWeightConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS_STRATEGY,
+                ConfigOptions.RemoteDataDirStrategy.WEIGHTED_ROUND_ROBIN);
+        negativeWeightConf.set(
+                ConfigOptions.REMOTE_DATA_DIRS, Arrays.asList("s3://bucket1", "s3://bucket2"));
+        negativeWeightConf.set(ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS, Arrays.asList(-1, 2));
+        assertThatThrownBy(() -> validateCoordinatorConfigs(negativeWeightConf))
+                .isInstanceOf(IllegalConfigurationException.class)
+                .hasMessageContaining(ConfigOptions.REMOTE_DATA_DIRS_WEIGHTS.key())
+                .hasMessageContaining(
+                        "All weights in 'remote.data.dirs.weights' must be no less than 0");
+    }
 }