Convert proto IndexedFields to bytes in Lucene and Fake index

See change 339790 for the background. We now support storing protos
directly in indexes.  In the follow up changes, we convert some byte
fields to be stored as protos. For all existing index
implementations, those fields will be still stored as bytes (i.e the
proto values will be converted to bytes on document creation). New
index implementations may choose to store protos directly. This makes
it possible to e.g. define searches on proto fields.

Release-Notes: skip
Change-Id: I655cdaa5933964baf06e83464d1aeb1a05d91d1d

java/com/google/gerrit/index/SchemaFieldDefs.java

diff --git a/java/com/google/gerrit/index/SchemaFieldDefs.java b/java/com/google/gerrit/index/SchemaFieldDefs.java
index e0b5dd2..db45b8d 100644
--- a/java/com/google/gerrit/index/SchemaFieldDefs.java
+++ b/java/com/google/gerrit/index/SchemaFieldDefs.java
@@ -100,4 +100,12 @@
   public interface Setter<I, T> {
     void set(I object, T value);
   }
+
+  public static boolean isProtoField(SchemaField<?, ?> schemaField) {
+    if (!(schemaField instanceof IndexedField<?, ?>.SearchSpec)) {
+      return false;
+    }
+    IndexedField<?, ?> indexedField = ((IndexedField<?, ?>.SearchSpec) schemaField).getField();
+    return indexedField.isProtoType() || indexedField.isProtoIterableType();
+  }
 }

java/com/google/gerrit/index/testing/AbstractFakeIndex.java

diff --git a/java/com/google/gerrit/index/testing/AbstractFakeIndex.java b/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
index 591ae26..5838ff1 100644
--- a/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
+++ b/java/com/google/gerrit/index/testing/AbstractFakeIndex.java
@@ -28,6 +28,7 @@
 import com.google.gerrit.index.Index;
 import com.google.gerrit.index.QueryOptions;
 import com.google.gerrit.index.Schema;
+import com.google.gerrit.index.SchemaFieldDefs;
 import com.google.gerrit.index.SchemaFieldDefs.SchemaField;
 import com.google.gerrit.index.project.ProjectData;
 import com.google.gerrit.index.project.ProjectIndex;
@@ -269,7 +270,8 @@
               Project.nameKey((String) doc.get(ChangeField.PROJECT_SPEC.getName())),
               Change.id(Integer.valueOf((String) doc.get(ChangeField.LEGACY_ID_STR.getName()))));
       for (SchemaField<ChangeData, ?> field : getSchema().getSchemaFields().values()) {
-        field.setIfPossible(cd, new FakeStoredValue(doc.get(field.getName())));
+        boolean isProtoField = SchemaFieldDefs.isProtoField(field);
+        field.setIfPossible(cd, new FakeStoredValue(doc.get(field.getName()), isProtoField));
       }
       return cd;
     }

java/com/google/gerrit/lucene/AbstractLuceneIndex.java

diff --git a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
index 6eac6f7..c158c65 100644
--- a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
+++ b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
@@ -38,16 +38,19 @@
 import com.google.gerrit.index.QueryOptions;
 import com.google.gerrit.index.Schema;
 import com.google.gerrit.index.Schema.Values;
+import com.google.gerrit.index.SchemaFieldDefs;
 import com.google.gerrit.index.SchemaFieldDefs.SchemaField;
 import com.google.gerrit.index.query.DataSource;
 import com.google.gerrit.index.query.FieldBundle;
 import com.google.gerrit.index.query.ListResultSet;
 import com.google.gerrit.index.query.ResultSet;
+import com.google.gerrit.proto.Protos;
 import com.google.gerrit.server.config.SitePaths;
 import com.google.gerrit.server.index.IndexUtils;
 import com.google.gerrit.server.index.options.AutoFlush;
 import com.google.gerrit.server.logging.LoggingContextAwareExecutorService;
 import com.google.gerrit.server.logging.LoggingContextAwareScheduledExecutorService;
+import com.google.protobuf.MessageLite;
 import java.io.IOException;
 import java.sql.Timestamp;
 import java.util.Set;
@@ -366,8 +369,12 @@
         doc.add(new TextField(name, (String) value, store));
       }
     } else if (type == FieldType.STORED_ONLY) {
+      boolean isProtoField = SchemaFieldDefs.isProtoField(values.getField());
       for (Object value : values.getValues()) {
-        doc.add(new StoredField(name, (byte[]) value));
+        // Lucene stores protos as bytes
+        doc.add(
+            new StoredField(
+                name, isProtoField ? Protos.toByteArray((MessageLite) value) : (byte[]) value));
       }
     } else {
       throw FieldType.badFieldType(type);