All available fulltext schema index analyzers now have useful descrip…

…tions explaining what they do and what they are for.

community/community-it/index-it/src/test/java/org/neo4j/kernel/api/impl/fulltext/FulltextProceduresTest.java

@@ -702,6 +702,7 @@ public void mustBeAbleToListAvailableAnalyzers()
     {
         db = createDatabase();
 
+        // Verify that a couple of expected analyzers are available.
         try ( Transaction tx = db.beginTx() )
         {
             Set<String> analyzers = new HashSet<>();
@@ -717,6 +718,24 @@ public void mustBeAbleToListAvailableAnalyzers()
             assertThat( analyzers, hasItem( "standard" ) );
             tx.success();
         }
+
+        // Verify that all analyzers have a description.
+        try ( Transaction tx = db.beginTx() )
+        {
+            try ( Result result = db.execute( LIST_AVAILABLE_ANALYZERS ) )
+            {
+                while ( result.hasNext() )
+                {
+                    Map<String,Object> row = result.next();
+                    Object description = row.get( "description" );
+                    if ( !row.containsKey( "description" ) || !(description instanceof String) || ((String) description).trim().isEmpty() )
+                    {
+                        fail( "Found no description for analyzer: " + row );
+                    }
+                }
+            }
+            tx.success();
+        }
     }
 
     @Test

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/FulltextAdapter.java

@@ -25,6 +25,7 @@
 import java.util.Properties;
 import java.util.stream.Stream;
 
+import org.neo4j.graphdb.index.fulltext.AnalyzerProvider;
 import org.neo4j.internal.kernel.api.exceptions.schema.IndexNotFoundKernelException;
 import org.neo4j.internal.kernel.api.schema.SchemaDescriptor;
 import org.neo4j.kernel.api.KernelTransaction;
@@ -38,5 +39,5 @@ public interface FulltextAdapter
 
     void awaitRefresh();
 
-    Stream<String> listAvailableAnalyzers();
+    Stream<AnalyzerProvider> listAvailableAnalyzers();
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/FulltextIndexProvider.java

@@ -327,11 +327,10 @@ public void awaitRefresh()
     }
 
     @Override
-    public Stream<String> listAvailableAnalyzers()
+    public Stream<AnalyzerProvider> listAvailableAnalyzers()
     {
         Iterable<AnalyzerProvider> providers = AnalyzerProvider.load( AnalyzerProvider.class );
-        Stream<AnalyzerProvider> stream = StreamSupport.stream( providers.spliterator(), false );
-        return stream.flatMap( provider -> StreamSupport.stream( provider.getKeys().spliterator(), false ) );
+        return StreamSupport.stream( providers.spliterator(), false );
     }
 
     @Override

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/FulltextProcedures.java

@@ -28,14 +28,17 @@
 import java.util.Objects;
 import java.util.Optional;
 import java.util.Properties;
+import java.util.Spliterator;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
 
 import org.neo4j.graphdb.DependencyResolver;
 import org.neo4j.graphdb.GraphDatabaseService;
 import org.neo4j.graphdb.Node;
 import org.neo4j.graphdb.NotFoundException;
 import org.neo4j.graphdb.Relationship;
+import org.neo4j.graphdb.index.fulltext.AnalyzerProvider;
 import org.neo4j.graphdb.schema.IndexDefinition;
 import org.neo4j.graphdb.schema.Schema;
 import org.neo4j.internal.kernel.api.IndexReference;
@@ -87,7 +90,13 @@ public class FulltextProcedures
     @Procedure( name = "db.index.fulltext.listAvailableAnalyzers", mode = READ )
     public Stream<AvailableAnalyzer> listAvailableAnalyzers()
     {
-        return accessor.listAvailableAnalyzers().map( AvailableAnalyzer::new );
+        Stream<AnalyzerProvider> stream = accessor.listAvailableAnalyzers();
+        return stream.flatMap( provider ->
+        {
+            String description = provider.description();
+            Spliterator<String> spliterator = provider.getKeys().spliterator();
+            return StreamSupport.stream( spliterator, false ).map( name -> new AvailableAnalyzer( name, description ) );
+        } );
     }
 
     @Description( "Wait for the updates from recently committed transactions to be applied to any eventually-consistent fulltext indexes." )
@@ -285,10 +294,12 @@ public static RelationshipOutput forExistingEntityOrNull( GraphDatabaseService d
     public static final class AvailableAnalyzer
     {
         public final String analyzer;
+        public final String description;
 
-        AvailableAnalyzer( String analyzer )
+        AvailableAnalyzer( String name, String description )
         {
-            this.analyzer = analyzer;
+            this.analyzer = name;
+            this.description = description;
         }
     }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Arabic.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new ArabicAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Arabic analyzer with light stemming, as specified by \"Light Stemming for Arabic Information Retrieval\".";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Armenian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new ArmenianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Armenian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Basque.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new BasqueAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Basque analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Brazilian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new BrazilianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Brazilian Portuguese analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Bulgarian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new BulgarianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Bulgarian analyzer with light stemming, as specified by \"Searching Strategies for the Bulgarian Language\", and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/CJK.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new CJKAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "CJK - Chinese/Japanese/Korean - analyzer. Terms are normalised and case-folded. Produces bi-grams, and filters out stop words.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Catalan.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new CatalanAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Catalan analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Classic.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new ClassicAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Classic Lucene analyzer. Similar to 'standard', but with worse unicode support.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Czech.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new CzechAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Czech analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Danish.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new DanishAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Danish analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Dutch.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new DutchAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Dutch analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/English.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new EnglishAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "English analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Finnish.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new FinnishAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Finnish analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/French.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new FrenchAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "French analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Galician.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new GalicianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Galician analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/German.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new GermanAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "German analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Greek.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new GreekAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Greek analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Hindi.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new HindiAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Hindi analyzer with stemming, normalization, and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Hungarian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new HungarianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Hungarian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Indonesian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new IndonesianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Indonesian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Irish.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new IrishAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Irish analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Italian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new ItalianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Italian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Keyword.java

@@ -38,4 +38,11 @@ public Analyzer createAnalyzer()
     {
         return new KeywordAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Keyword analyzer \"tokenizes\" the text as a single term. Useful for zip-codes, ids, etc. " +
+                "Situations where complete and exact matches are desired.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Latvian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new LatvianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Latvian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Lithuanian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new LithuanianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Lithuanian analyzer with stemming and stop word filtering.";
+    }
 }

community/fulltext-index/src/main/java/org/neo4j/kernel/api/impl/fulltext/analyzer/providers/Norwegian.java

@@ -38,4 +38,10 @@ public Analyzer createAnalyzer()
     {
         return new NorwegianAnalyzer();
     }
+
+    @Override
+    public String description()
+    {
+        return "Norwegian analyzer with stemming and stop word filtering.";
+    }
 }