fetch available values for gallery via autocomplete method

We had a method that returned the values of a field
with respect to a query. That method was inefficient,
because it executed the query, fetched all Docs
and collected the values.
The autocomplete method we introduced a while back
can answer the same question but much more efficiently.

data-store/src/main/java/org/lucares/pdb/datastore/internal/DataStore.java

@@ -10,8 +10,6 @@ import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
-import java.util.SortedSet;
-import java.util.TreeSet;
 import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.Consumer;
 
@@ -229,28 +227,6 @@ public class DataStore implements AutoCloseable {
 
 	}
 
-	public SortedSet<String> getAvailableValuesForKey(final Query query, final String key) {
-
-		final SortedSet<String> result = new TreeSet<>();
-		if (query.getQuery().isEmpty()) {
-			final PartitionIdSource partitionIdSource = new DatePartitioner(query.getDateRange());
-			tagToDocsId.visitValues(partitionIdSource, new Tag(key, ""),
-					(tag, __) -> result.add(tag.getValueAsString()));
-		} else {
-			final List<Doc> docs = search(query);
-			for (final Doc doc : docs) {
-				final String valueForKey = doc.getTags().getValue(key);
-
-				if (valueForKey != null) {
-					result.add(valueForKey);
-				}
-			}
-		}
-
-		return result;
-
-	}
-
 	private PartitionLongList executeQuery(final Query query) {
 		final long start = System.nanoTime();
 		synchronized (docIdToDoc) {

pdb-ui/src/main/java/org/lucares/pdbui/PdbController.java

@@ -11,12 +11,12 @@ import java.util.List;
 import java.util.Locale;
 import java.util.Map;
 import java.util.SortedSet;
+import java.util.TreeSet;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
 
 import org.apache.commons.lang3.StringUtils;
 import org.lucares.pdb.api.DateTimeRange;
-import org.lucares.pdb.api.Query;
 import org.lucares.pdb.api.QueryWithCaretMarker;
 import org.lucares.pdb.datastore.Proposal;
 import org.lucares.pdb.plot.api.AxisScale;
@@ -252,9 +252,14 @@ public class PdbController implements HardcodedValues, PropertyKeys {
 	SortedSet<String> fields(@PathVariable(name = "fieldName") final String fieldName,
 			@RequestParam(name = "query") final String query) {
 
-		final DateTimeRange dateRange = DateTimeRange.max();
-		final Query q = new Query(query, dateRange);
-		final SortedSet<String> fields = db.getFieldsValues(q, fieldName);
+		final String q = String.format("(%s) and %s=", query, fieldName);
+		final int caretIndex = q.length() + 1; // the autocomplete methods needs a 1-based index
+
+		final AutocompleteResponse autocompleteResponse = this.autocomplete(q, caretIndex);
+		final List<AutocompleteProposal> proposals = autocompleteResponse.getProposals();
+
+		final SortedSet<String> fields = CollectionUtils.map(proposals, new TreeSet<>(),
+				AutocompleteProposal::getValue);
 
 		return fields;
 	}

pdb-utils/src/main/java/org/lucares/utils/CollectionUtils.java

@@ -34,6 +34,17 @@ public class CollectionUtils {
 		return Stream.of(input).map(mapper).collect(Collectors.toList());
 	}
 
+	public static <O extends Collection<R>, T, R> O map(final Collection<T> input, final O result,
+			final Function<T, R> mapper) {
+
+		for (final T t : input) {
+			final R e = mapper.apply(t);
+			result.add(e);
+		}
+
+		return result;
+	}
+
 	public static <T, V> Map<T, V> createMapFromValues(final Iterable<V> iterable, final Function<V, T> keyMapper) {
 		final Map<T, V> result = new HashMap<>();
 

performanceDb/src/main/java/org/lucares/performance/db/PerformanceDb.java

@@ -8,7 +8,6 @@ import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Optional;
-import java.util.SortedSet;
 import java.util.stream.Stream;
 
 import org.lucares.collections.LongList;
@@ -24,8 +23,8 @@ import org.lucares.pdb.datastore.InvalidValueException;
 import org.lucares.pdb.datastore.PdbFile;
 import org.lucares.pdb.datastore.Proposal;
 import org.lucares.pdb.datastore.WriteException;
-import org.lucares.pdb.datastore.internal.PartitionDiskStore;
 import org.lucares.pdb.datastore.internal.DataStore;
+import org.lucares.pdb.datastore.internal.PartitionDiskStore;
 import org.lucares.pdb.datastore.lang.SyntaxException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -181,10 +180,6 @@ public class PerformanceDb implements AutoCloseable {
 		return fields;
 	}
 
-	public SortedSet<String> getFieldsValues(final Query query, final String fieldName) {
-		return dataStore.getAvailableValuesForKey(query, fieldName);
-	}
-
 	public PartitionDiskStore getDataStore() {
 		return dataStore.getDiskStorage();
 	}