LanceSnapshotResolver.java

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.datasource.lance;

import org.lance.Version;

import java.time.Instant;
import java.util.Comparator;
import java.util.List;

/** Resolves Doris time-travel selectors to immutable Lance version IDs. */
final class LanceSnapshotResolver {
    private LanceSnapshotResolver() {
    }

    static long parseVersion(String value) {
        final long version;
        try {
            version = Long.parseLong(value);
        } catch (NumberFormatException e) {
            throw new IllegalArgumentException(
                    "Lance FOR VERSION AS OF requires a numeric version, but was '" + value + "'", e);
        }
        if (version <= 0) {
            throw new IllegalArgumentException(
                    "Lance FOR VERSION AS OF requires a positive version, but was " + version);
        }
        return version;
    }

    static long versionAtOrBefore(List<Version> versions, long timestampMillis) {
        Instant requestedTime = Instant.ofEpochMilli(timestampMillis);
        return versions.stream()
                .filter(version -> !version.getDataTime().toInstant().isAfter(requestedTime))
                .max(Comparator.comparing((Version version) -> version.getDataTime().toInstant())
                        .thenComparingLong(Version::getId))
                .orElseThrow(() -> new IllegalArgumentException(
                        "Lance dataset has no version at or before timestamp " + timestampMillis))
                .getId();
    }
}