Generate a Protobuf definition for the database
I added support for generating a file containing all the Protobuf
type definitions for a given database schema. The JavaSchemaModel now
has a method to output a Protobuf definition to a given PrintWriter.
This allows tools using a NoSQL database to have a Protobuf file
describing the Protobuf data in the database.
Change-Id: I53f4902d2b335be2b20d966fd0eb58c050e8a53c
diff --git a/src/main/java/com/google/gwtorm/schema/RelationModel.java b/src/main/java/com/google/gwtorm/schema/RelationModel.java
index de323f8..d835246 100644
--- a/src/main/java/com/google/gwtorm/schema/RelationModel.java
+++ b/src/main/java/com/google/gwtorm/schema/RelationModel.java
@@ -123,6 +123,10 @@
return relationName;
}
+ public int getRelationID() {
+ return relation.id();
+ }
+
public Collection<ColumnModel> getDependentFields() {
final ArrayList<ColumnModel> r = new ArrayList<ColumnModel>();
for (final ColumnModel c : fieldsByFieldName.values()) {
diff --git a/src/main/java/com/google/gwtorm/schema/java/JavaSchemaModel.java b/src/main/java/com/google/gwtorm/schema/java/JavaSchemaModel.java
index b8a0748..390ef3e 100644
--- a/src/main/java/com/google/gwtorm/schema/java/JavaSchemaModel.java
+++ b/src/main/java/com/google/gwtorm/schema/java/JavaSchemaModel.java
@@ -22,6 +22,7 @@
import com.google.gwtorm.schema.SchemaModel;
import com.google.gwtorm.schema.SequenceModel;
+import java.io.PrintWriter;
import java.lang.reflect.Method;
@@ -65,6 +66,11 @@
throw new IllegalArgumentException("No relation named " + name);
}
+ public void generateProto(PrintWriter out) {
+ ProtoFileGenerator pfg = new ProtoFileGenerator(schema.getSimpleName(), getRelations());
+ pfg.print(out);
+ }
+
@Override
public String getSchemaClassName() {
return schema.getName();
diff --git a/src/main/java/com/google/gwtorm/schema/java/ProtoFileGenerator.java b/src/main/java/com/google/gwtorm/schema/java/ProtoFileGenerator.java
new file mode 100644
index 0000000..66f617e
--- /dev/null
+++ b/src/main/java/com/google/gwtorm/schema/java/ProtoFileGenerator.java
@@ -0,0 +1,209 @@
+// Copyright 2010 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gwtorm.schema.java;
+
+import com.google.gwtorm.client.Column;
+import com.google.gwtorm.schema.ColumnModel;
+import com.google.gwtorm.schema.RelationModel;
+
+import org.objectweb.asm.Type;
+
+import java.io.PrintWriter;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.HashSet;
+import java.util.List;
+
+class ProtoFileGenerator {
+ private static final Comparator<ColumnModel> COLUMN_COMPARATOR =
+ new Comparator<ColumnModel>() {
+ @Override
+ public int compare(ColumnModel o1, ColumnModel o2) {
+ return o1.getColumnID() - o2.getColumnID();
+ }
+ };
+
+ private static final Comparator<RelationModel> RELATION_COMPARATOR =
+ new Comparator<RelationModel>() {
+ @Override
+ public int compare(RelationModel o1, RelationModel o2) {
+ return o1.getRelationID() - o2.getRelationID();
+ }
+ };
+
+ private final Collection<RelationModel> rels;
+ private final String schemaName;
+ private final HashSet<String> seen;
+ private final HashSet<String> collisions;
+
+ ProtoFileGenerator(String schemaName, Collection<RelationModel> relations) {
+ this.schemaName = schemaName;
+ this.rels = relations;
+ this.seen = new HashSet<String>();
+ this.collisions = new HashSet<String>();
+ }
+
+ void print(PrintWriter out) {
+ seen.clear();
+ collisions.clear();
+
+ for (RelationModel r : rels) {
+ for (ColumnModel c : r.getColumns()) {
+ if (c.isNested()) {
+ String type = getShortClassName(c);
+ if (seen.contains(type)) {
+ collisions.add(type);
+ } else {
+ seen.add(type);
+ }
+ }
+ }
+ }
+
+ seen.clear();
+ for (RelationModel r : rels) {
+ generateMessage(r, out);
+ }
+
+ out.print("message " + schemaName + " {\n");
+
+ for (RelationModel r : sortRelations(rels)) {
+ out.print("\toptional " + getMessageName(r) + " "
+ + r.getRelationName().toLowerCase() + " = " + r.getRelationID()
+ + ";\n");
+ }
+
+ out.print("}\n");
+ }
+
+ private void generateMessage(RelationModel rel, PrintWriter out) {
+ List<ColumnModel> cols = sortColumns(rel.getFields());
+ for (ColumnModel c : cols) {
+ generateMessage(c, out);
+ }
+
+ out.print("message " + getMessageName(rel) + " {\n");
+ for (ColumnModel c : cols) {
+ out.append("\toptional " + getType(c) + " " + getName(c) + " = "
+ + c.getColumnID() + ";\n");
+ }
+ out.print("}\n\n");
+ }
+
+ private void generateMessage(ColumnModel parent, PrintWriter out) {
+ // Handle base cases
+ if (!parent.isNested()) {
+ return;
+ } else if (seen.contains(parent.getNestedClassName())) {
+ return;
+ }
+
+ List<ColumnModel> children = sortColumns(parent.getNestedColumns());
+ for (ColumnModel child : children) {
+ generateMessage(child, out);
+ }
+
+ out.print("message " + getType(parent) + " {\n");
+ for (ColumnModel child : children) {
+ out.append("\toptional " + getType(child) + " " + getName(child) + " = "
+ + child.getColumnID() + ";\n");
+ }
+ out.print("}\n\n");
+
+ seen.add(parent.getNestedClassName());
+ }
+
+ private String getType(ColumnModel cm) {
+ if (cm.isNested()) {
+ String type = getShortClassName(cm);
+ if (collisions.contains(type)) {
+ return cm.getNestedClassName().replace('.', '_').replace('$', '_');
+ } else {
+ return type;
+ }
+ } else {
+ return toProtoType(cm.getPrimitiveType());
+ }
+ }
+
+ private static String getName(ColumnModel cm) {
+ if (cm.getColumnName().equals(Column.NONE)) {
+ return cm.getFieldName();
+ } else {
+ return cm.getColumnName();
+ }
+ }
+
+ private static String getShortClassName(ColumnModel cm) {
+ String tmp = cm.getNestedClassName();
+ return tmp.substring(tmp.lastIndexOf('.') + 1).replace('$', '_');
+ }
+
+ private static String getMessageName(RelationModel r) {
+ String typeName = r.getEntityTypeClassName();
+ return typeName.substring(typeName.lastIndexOf('.') + 1);
+ }
+
+ private static List<ColumnModel> sortColumns(Collection<ColumnModel> cols) {
+ ArrayList<ColumnModel> list = new ArrayList<ColumnModel>(cols);
+ Collections.sort(list, COLUMN_COMPARATOR);
+ return list;
+ }
+
+ private static List<RelationModel> sortRelations(
+ Collection<RelationModel> rels) {
+ ArrayList<RelationModel> list = new ArrayList<RelationModel>(rels);
+ Collections.sort(list, RELATION_COMPARATOR);
+ return list;
+ }
+
+ private static String toProtoType(Class<?> clazz) {
+ switch (Type.getType(clazz).getSort()) {
+ case Type.BOOLEAN:
+ return "bool";
+ case Type.CHAR:
+ return "uint32";
+ case Type.BYTE:
+ case Type.SHORT:
+ case Type.INT:
+ return "sint32";
+ case Type.FLOAT:
+ return "float";
+ case Type.DOUBLE:
+ return "double";
+ case Type.LONG:
+ return "sint64";
+ case Type.ARRAY:
+ case Type.OBJECT: {
+ if (clazz == byte[].class) {
+ return "bytes";
+ } else if (clazz == String.class) {
+ return "string";
+ } else if (clazz == java.sql.Timestamp.class) {
+ return "fixed64";
+ } else {
+ throw new RuntimeException("Type " + clazz
+ + " not supported on protobuf!");
+ }
+ }
+
+ default:
+ throw new RuntimeException("Type " + clazz
+ + " not supported on protobuf!");
+ }
+ }
+}
