Allow sorting in the API calls by path and date

Signed-off-by: Bernát Gábor <gaborjbernat@gmail.com>

Author: gaborbernat

opengrok-indexer/src/main/java/org/opengrok/indexer/search/SearchEngine.java

@@ -48,6 +48,9 @@
 import org.apache.lucene.search.IndexSearcher;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.ScoreDoc;
+import org.apache.lucene.search.Sort;
+import org.apache.lucene.search.SortField;
+import org.apache.lucene.search.TopFieldCollector;
 import org.apache.lucene.search.TopScoreDocCollector;
 import org.apache.lucene.util.Version;
 import org.opengrok.indexer.analysis.AbstractAnalyzer;
@@ -66,6 +69,7 @@
 import org.opengrok.indexer.util.Statistics;
 import org.opengrok.indexer.util.TandemPath;
 import org.opengrok.indexer.web.Prefix;
+import org.opengrok.indexer.web.SortOrder;
 
 /**
  * This is an encapsulation of the details on how to search in the index database.
@@ -114,6 +118,10 @@ public class SearchEngine {
      * Holds value of property type.
      */
     private String type;
+    /**
+     * Holds value of property sort.
+     */
+    private SortOrder sortOrder;
     /**
      * Holds value of property indexDatabase.
      */
@@ -181,6 +189,10 @@ private void searchSingleDatabase(boolean paging) throws IOException {
         SuperIndexSearcher superIndexSearcher = RuntimeEnvironment.getInstance().getSuperIndexSearcher("");
         searcherList.add(superIndexSearcher);
         searcher = superIndexSearcher;
+        // If a field-based sort is requested, collect all hits (disable paging optimization)
+        if (sortOrder != SortOrder.RELEVANCY) {
+            paging = false;
+        }
         searchIndex(superIndexSearcher, paging);
     }
 
@@ -205,18 +217,42 @@ private void searchMultiDatabase(List<Project> projectList, boolean paging) thro
     }
 
     private void searchIndex(IndexSearcher searcher, boolean paging) throws IOException {
-        collector = TopScoreDocCollector.create(hitsPerPage * cachePages, Short.MAX_VALUE);
+        // Determine if we need a field-based sort or relevancy (score) sort.
+        Sort luceneSort = null;
+        if (getSortOrder() == SortOrder.LASTMODIFIED) {
+            // Descending by date (newest first) - QueryBuilder.DATE is string sortable in index.
+            luceneSort = new Sort(new SortField(QueryBuilder.DATE, SortField.Type.STRING, true));
+        } else if (getSortOrder() == SortOrder.BY_PATH) {
+            luceneSort = new Sort(new SortField(QueryBuilder.FULLPATH, SortField.Type.STRING));
+        }
+
         Statistics stat = new Statistics();
-        searcher.search(query, collector);
-        totalHits = collector.getTotalHits();
-        stat.report(LOGGER, Level.FINEST, "search via SearchEngine done",
-                "search.latency", new String[]{"category", "engine",
-                        "outcome", totalHits > 0 ? "success" : "empty"});
-        if (!paging && totalHits > 0) {
-            collector = TopScoreDocCollector.create(totalHits, Short.MAX_VALUE);
+        if (luceneSort == null) {
+            collector = TopScoreDocCollector.create(hitsPerPage * cachePages, Short.MAX_VALUE);
             searcher.search(query, collector);
+            totalHits = collector.getTotalHits();
+            stat.report(LOGGER, Level.FINEST, "search via SearchEngine done",
+                    "search.latency", new String[]{"category", "engine",
+                            "outcome", totalHits > 0 ? "success" : "empty"});
+            if (!paging && totalHits > 0) {
+                collector = TopScoreDocCollector.create(totalHits, Short.MAX_VALUE);
+                searcher.search(query, collector);
+            }
+            hits = collector.topDocs().scoreDocs;
+        } else {
+            // Field based sort; use TopFieldCollector
+            TopFieldCollector fieldCollector = TopFieldCollector.create(luceneSort, hitsPerPage * cachePages, Short.MAX_VALUE);
+            searcher.search(query, fieldCollector);
+            totalHits = fieldCollector.getTotalHits();
+            stat.report(LOGGER, Level.FINEST, "search via SearchEngine done (sorted)",
+                    "search.latency", new String[]{"category", "engine",
+                            "outcome", totalHits > 0 ? "success" : "empty"});
+            if (!paging && totalHits > 0) {
+                fieldCollector = TopFieldCollector.create(luceneSort, totalHits, Short.MAX_VALUE);
+                searcher.search(query, fieldCollector);
+            }
+            hits = fieldCollector.topDocs().scoreDocs;
         }
-        hits = collector.topDocs().scoreDocs;
         StoredFields storedFields = searcher.storedFields();
         for (ScoreDoc hit : hits) {
             int docId = hit.doc;
@@ -645,4 +681,22 @@ public String getType() {
     public void setType(String fileType) {
         this.type = fileType;
     }
+
+    /**
+     * Getter for property sort.
+     *
+     * @return Value of property sortOrder.
+     */
+    public SortOrder getSortOrder() {
+        return this.sortOrder;
+    }
+
+    /**
+     * Setter for property sort.
+     *
+     * @param sortOrder New value of property sortOrder.
+     */
+    public void setSortOrder(SortOrder sortOrder) {
+        this.sortOrder = sortOrder;
+    }
 }

opengrok-web/src/main/java/org/opengrok/web/api/v1/controller/SearchController.java

@@ -39,6 +39,7 @@
 import org.opengrok.indexer.search.Hit;
 import org.opengrok.indexer.search.SearchEngine;
 import org.opengrok.indexer.web.QueryParameters;
+import org.opengrok.indexer.web.SortOrder;
 import org.opengrok.web.PageConfig;
 import org.opengrok.web.api.v1.filter.CorsEnable;
 import org.opengrok.web.api.v1.suggester.provider.service.SuggesterService;
@@ -81,9 +82,10 @@ public SearchResult search(
             @QueryParam("projects") final List<String> projects,
             @QueryParam("maxresults") // Akin to QueryParameters.COUNT_PARAM
             @DefaultValue(MAX_RESULTS + "") final int maxResults,
+            @QueryParam(QueryParameters.SORT_PARAM) @DefaultValue("relevancy") final String sort,
             @QueryParam(QueryParameters.START_PARAM) @DefaultValue(0 + "") final int startDocIndex
     ) {
-        try (SearchEngineWrapper engine = new SearchEngineWrapper(full, def, symbol, path, hist, type)) {
+        try (SearchEngineWrapper engine = new SearchEngineWrapper(full, def, symbol, path, hist, type, SortOrder.get(sort))) {
 
             if (!engine.isValid()) {
                 throw new WebApplicationException("Invalid request", Response.Status.BAD_REQUEST);
@@ -119,14 +121,16 @@ private SearchEngineWrapper(
                 final String symbol,
                 final String path,
                 final String hist,
-                final String type
+                final String type,
+                final SortOrder sortOrder
         ) {
             engine.setFreetext(full);
             engine.setDefinition(def);
             engine.setSymbol(symbol);
             engine.setFile(path);
             engine.setHistory(hist);
             engine.setType(type);
+            engine.setSortOrder(sortOrder);
         }
 
         public List<Hit> search(