Examples with IndexScanRange com.apple.foundationdb.record.provider.foundationdb.IndexScanRange used on opensource projects

Example 1 with IndexScanRange

use of com.apple.foundationdb.record.provider.foundationdb.IndexScanRange in project fdb-record-layer by FoundationDB.

the class TimeWindowLeaderboardIndexMaintainer method scan.

@Nonnull
@Override
public RecordCursor<IndexEntry> scan(@Nonnull IndexScanBounds scanBounds, @Nullable byte[] continuation, @Nonnull ScanProperties scanProperties) {
    final IndexScanType scanType = scanBounds.getScanType();
    if (scanType != IndexScanType.BY_VALUE && scanType != IndexScanType.BY_RANK && scanType != IndexScanType.BY_TIME_WINDOW) {
        throw new RecordCoreException("Can only scan leaderboard index by time window, rank or value.");
    }
    // Decode range arguments.
    final int type;
    final long timestamp;
    final TupleRange leaderboardRange;
    if (scanType == IndexScanType.BY_TIME_WINDOW) {
        // Get oldest leaderboard of type containing timestamp.
        if (scanBounds instanceof TimeWindowScanRange) {
            TimeWindowScanRange scanRange = (TimeWindowScanRange) scanBounds;
            type = scanRange.getLeaderboardType();
            timestamp = scanRange.getLeaderboardTimestamp();
            leaderboardRange = scanRange.getScanRange();
        } else {
            // TODO: For compatibility, accept scan with BY_TIME_WINDOW and TupleRange for a while.
            // This code can be removed when we are confident all callers have been converted.
            IndexScanRange scanRange = (IndexScanRange) scanBounds;
            TupleRange rankRange = scanRange.getScanRange();
            final Tuple lowRank = rankRange.getLow();
            final Tuple highRank = rankRange.getHigh();
            type = (int) lowRank.getLong(0);
            timestamp = lowRank.getLong(1);
            leaderboardRange = new TupleRange(Tuple.fromList(lowRank.getItems().subList(2, lowRank.size())), Tuple.fromList(highRank.getItems().subList(2, highRank.size())), rankRange.getLowEndpoint(), rankRange.getHighEndpoint());
        }
    } else {
        // Get the all-time leaderboard for unqualified rank or value.
        IndexScanRange scanRange = (IndexScanRange) scanBounds;
        type = TimeWindowLeaderboard.ALL_TIME_LEADERBOARD_TYPE;
        // Any value would do.
        timestamp = 0;
        leaderboardRange = scanRange.getScanRange();
    }
    final int groupPrefixSize = getGroupingCount();
    final CompletableFuture<TimeWindowLeaderboard> leaderboardFuture = oldestLeaderboardMatching(type, timestamp);
    final CompletableFuture<TupleRange> scoreRangeFuture;
    if (scanType == IndexScanType.BY_VALUE) {
        scoreRangeFuture = leaderboardFuture.thenApply(leaderboard -> leaderboard == null ? null : leaderboardRange);
    } else {
        scoreRangeFuture = leaderboardFuture.thenCompose(leaderboard -> {
            if (leaderboard == null) {
                return CompletableFuture.completedFuture(null);
            }
            final Subspace extraSubspace = getSecondarySubspace();
            final Subspace leaderboardSubspace = extraSubspace.subspace(leaderboard.getSubspaceKey());
            final RankedSet.Config leaderboardConfig = config.toBuilder().setNLevels(leaderboard.getNLevels()).build();
            return RankedSetIndexHelper.rankRangeToScoreRange(state, groupPrefixSize, leaderboardSubspace, leaderboardConfig, leaderboardRange);
        });
    }
    // Add leaderboard's key to the front and take it off of the results.
    return RecordCursor.flatMapPipelined(ignore -> RecordCursor.fromFuture(getExecutor(), scoreRangeFuture), (scoreRange, ignore) -> {
        if (scoreRange == null) {
            return RecordCursor.empty(getExecutor());
        }
        // Already waited in scoreRangeFuture.
        final TimeWindowLeaderboard leaderboard = state.context.joinNow(leaderboardFuture);
        final CompletableFuture<Boolean> highStoreFirstFuture;
        if (scanType == IndexScanType.BY_VALUE) {
            final Tuple lowGroup = scoreRange.getLow() != null && scoreRange.getLow().size() > groupPrefixSize ? TupleHelpers.subTuple(scoreRange.getLow(), 0, groupPrefixSize) : null;
            final Tuple highGroup = scoreRange.getHigh() != null && scoreRange.getHigh().size() > groupPrefixSize ? TupleHelpers.subTuple(scoreRange.getHigh(), 0, groupPrefixSize) : null;
            if (lowGroup != null && lowGroup.equals(highGroup)) {
                highStoreFirstFuture = isHighScoreFirst(leaderboard.getDirectory(), lowGroup);
            } else {
                highStoreFirstFuture = CompletableFuture.completedFuture(leaderboard.getDirectory().isHighScoreFirst());
            }
        } else {
            highStoreFirstFuture = AsyncUtil.READY_FALSE;
        }
        if (highStoreFirstFuture.isDone()) {
            return scanLeaderboard(leaderboard, state.context.joinNow(highStoreFirstFuture), scoreRange, continuation, scanProperties);
        } else {
            return RecordCursor.flatMapPipelined(ignore2 -> RecordCursor.fromFuture(getExecutor(), highStoreFirstFuture), (highScoreFirst, ignore2) -> scanLeaderboard(leaderboard, highScoreFirst, scoreRange, continuation, scanProperties), null, 1);
        }
    }, null, 1).mapPipelined(kv -> getIndexEntry(kv, groupPrefixSize, state.context.joinNow(leaderboardFuture).getDirectory()), 1);
}