Support PostgreSQL and CockroachDB backends

.travis.yml

@@ -80,6 +80,7 @@ env:
     - BACKEND=mysql
     - BACKEND=hbase
     - BACKEND=rocksdb
+    - BACKEND=postgresql
   global:
     - RELEASE_BRANCH=^release-.*$
     - RELEASE_TAG=^v[0-9]\..*$

hugegraph-cassandra/src/main/java/com/baidu/hugegraph/backend/store/cassandra/CassandraTable.java

@@ -266,9 +266,6 @@ protected Clause relation2Cql(Relation relation) {
         String key = relation.serialKey().toString();
         Object value = relation.serialValue();
 
-        // Serialize value (TODO: should move to Serializer)
-        value = serializeValue(value);
-
         switch (relation.relation()) {
             case EQ:
                 return QueryBuilder.eq(key, value);
@@ -281,12 +278,7 @@ protected Clause relation2Cql(Relation relation) {
             case LTE:
                 return QueryBuilder.lte(key, value);
             case IN:
-                List<?> values = (List<?>) value;
-                List<Object> serializedValues = new ArrayList<>(values.size());
-                for (Object v : values) {
-                    serializedValues.add(serializeValue(v));
-                }
-                return QueryBuilder.in(key, serializedValues);
+                return QueryBuilder.in(key, value);
             case CONTAINS:
                 return QueryBuilder.contains(key, value);
             case CONTAINS_KEY:
@@ -331,14 +323,6 @@ protected static Select cloneSelect(Select select, String table) {
         return CopyUtil.copy(select, QueryBuilder.select().from(table));
     }
 
-    protected static Object serializeValue(Object value) {
-        // Serialize value (TODO: should move to Serializer)
-        if (value instanceof Id) {
-            value = ((Id) value).asObject();
-        }
-        return value;
-    }
-
     protected Iterator<BackendEntry> results2Entries(Query q, ResultSet r) {
         return new CassandraEntryIterator(r, q, (e1, row) -> {
             CassandraBackendEntry e2 = row2Entry(q.resultType(), row);

hugegraph-core/src/main/java/com/baidu/hugegraph/backend/serializer/TableSerializer.java

@@ -19,7 +19,9 @@
 
 package com.baidu.hugegraph.backend.serializer;
 
+import java.util.ArrayList;
 import java.util.Collection;
+import java.util.List;
 import java.util.Set;
 
 import com.baidu.hugegraph.HugeGraph;
@@ -339,7 +341,8 @@ protected Query writeQueryEdgeCondition(Query query) {
                 if (r.key() == HugeKeys.OWNER_VERTEX ||
                     r.key() == HugeKeys.OTHER_VERTEX) {
                     // Serialize vertex id
-                    r.serialValue(IdUtil.writeString((Id) value));
+                    String id = IdUtil.writeString((Id) value);
+                    r.serialValue(this.escapeString(id));
                 } else {
                     // Serialize label id
                     r.serialValue(((Id) value).asObject());
@@ -353,16 +356,30 @@ protected Query writeQueryEdgeCondition(Query query) {
 
     @Override
     protected Query writeQueryCondition(Query query) {
-        if (query.resultType().isGraph()) {
-            ConditionQuery result = (ConditionQuery) query;
-            // No user-prop when serialize
-            assert result.allSysprop();
-            for (Condition.Relation r : result.relations()) {
-                if (r.relation() == Condition.RelationType.CONTAINS) {
-                    r.serialValue(JsonUtil.toJson(r.value()));
+        ConditionQuery result = (ConditionQuery) query;
+        // No user-prop when serialize
+        assert result.allSysprop();
+        for (Condition.Relation r : result.relations()) {
+            if (!(r.value().equals(r.serialValue()))) {
+                continue;
+            }
+            if (r.relation() == Condition.RelationType.IN) {
+                List<?> values = (List<?>) r.value();
+                List<Object> serializedValues = new ArrayList<>(values.size());
+                for (Object v : values) {
+                    serializedValues.add(this.serializeValue(v));
                 }
+                r.serialValue(serializedValues);
+            } else {
+                r.serialValue(this.serializeValue(r.value()));
+            }
+
+            if (query.resultType().isGraph() &&
+                r.relation() == Condition.RelationType.CONTAINS) {
+                r.serialValue(JsonUtil.toJson(r.serialValue()));
             }
         }
+
         return query;
     }
 
@@ -577,6 +594,20 @@ protected abstract void formatProperties(HugeElement element,
     protected abstract void parseProperties(HugeElement element,
                                             TableBackendEntry.Row row);
 
+    protected Object serializeValue(Object value) {
+        if (value instanceof Id) {
+            value = ((Id) value).asObject();
+        }
+        if (value instanceof String) {
+            value = this.escapeString((String) value);
+        }
+        return value;
+    }
+
+    protected String escapeString(String value) {
+        return value;
+    }
+
     protected void writeEnableLabelIndex(SchemaLabel schema,
                                          TableBackendEntry entry) {
         entry.column(HugeKeys.ENABLE_LABEL_INDEX, schema.enableLabelIndex());

hugegraph-core/src/main/java/com/baidu/hugegraph/backend/store/TableDefine.java

@@ -28,21 +28,37 @@
 
 import com.baidu.hugegraph.type.define.HugeKeys;
 import com.baidu.hugegraph.util.InsertionOrderUtil;
+import com.google.common.collect.ImmutableMap;
 
 public class TableDefine {
 
     private final Map<HugeKeys, String> columns;
     private final List<HugeKeys> keys;
+    private final Map<String, String> typesMapping;
 
     public TableDefine() {
         this.columns = InsertionOrderUtil.newMap();
         this.keys = InsertionOrderUtil.newList();
+        this.typesMapping = ImmutableMap.of();
+    }
+
+    public TableDefine(Map<String, String> typesMapping) {
+        this.columns = InsertionOrderUtil.newMap();
+        this.keys = InsertionOrderUtil.newList();
+        this.typesMapping = typesMapping;
     }
 
     public TableDefine column(HugeKeys key, String... desc) {
         StringBuilder sb = new StringBuilder();
         for (int i = 0; i < desc.length; i++) {
-            sb.append(desc[i]);
+            String type = desc[i];
+            // The first element of 'desc' is column data type, which may be
+            // mapped to actual data type supported by backend store
+            if (i == 0 && this.typesMapping.containsKey(type)) {
+                type = this.typesMapping.get(type);
+            }
+            assert type != null;
+            sb.append(type);
             if (i != desc.length - 1) {
                 sb.append(" ");
             }

hugegraph-dist/pom.xml

@@ -59,6 +59,11 @@
             <artifactId>hugegraph-hbase</artifactId>
             <version>${project.version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.baidu.hugegraph</groupId>
+            <artifactId>hugegraph-postgresql</artifactId>
+            <version>${project.version}</version>
+        </dependency>
         <dependency>
             <groupId>io.airlift</groupId>
             <artifactId>airline</artifactId>

hugegraph-dist/src/assembly/static/conf/hugegraph.properties

@@ -33,12 +33,13 @@ cassandra.password=
 
 
 # mysql backend config
+#jdbc.driver=com.mysql.jdbc.Driver
 #jdbc.url=jdbc:mysql://127.0.0.1:3306
 #jdbc.username=root
 #jdbc.password=
 #jdbc.reconnect_max_times=3
 #jdbc.reconnect_interval=3
-
+#jdbc.sslmode=disable
 
 # palo backend config
 #palo.host=127.0.0.1

hugegraph-dist/src/assembly/travis/install-backend.sh

@@ -10,4 +10,6 @@ elif [ "$BACKEND" == "hbase" ]; then
     $TRAVIS_DIR/install-hbase.sh
 elif [ "$BACKEND" == "mysql" ]; then
     $TRAVIS_DIR/install-mysql.sh
+elif [ "$BACKEND" == "postgresql" ]; then
+    $TRAVIS_DIR/install-postgresql.sh
 fi

hugegraph-dist/src/assembly/travis/install-postgresql.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+set -ev
+
+TRAVIS_DIR=`dirname $0`
+CONF=hugegraph-test/src/main/resources/hugegraph.properties
+
+POSTGRESQL_DRIVER=org.postgresql.Driver
+POSTGRESQL_URL=jdbc:postgresql://localhost:5432/
+POSTGRESQL_USERNAME=postgres
+
+# Set PostgreSQL configurations
+sed -i "s/jdbc.driver=.*/jdbc.driver=$POSTGRESQL_DRIVER/" $CONF
+sed -i "s?jdbc.url=.*?jdbc.url=$POSTGRESQL_URL?" $CONF
+sed -i "s/jdbc.username=.*/jdbc.username=$POSTGRESQL_USERNAME/" $CONF
+
+sudo service postgresql stop 9.2
+sudo service postgresql start 9.5

hugegraph-dist/src/assembly/travis/start-server.sh

@@ -7,15 +7,29 @@ BASE_DIR=hugegraph-$VERSION
 BIN=$BASE_DIR/bin
 CONF=$BASE_DIR/conf/hugegraph.properties
 
+# PostgreSQL configurations
+POSTGRESQL_DRIVER=org.postgresql.Driver
+POSTGRESQL_URL=jdbc:postgresql://localhost:5432/
+POSTGRESQL_USERNAME=postgres
+
 declare -A backend_serializer_map=(["memory"]="text" ["cassandra"]="cassandra" \
                                    ["scylladb"]="scylladb" ["mysql"]="mysql" \
-                                   ["hbase"]="hbase" ["rocksdb"]="binary")
+                                   ["hbase"]="hbase" ["rocksdb"]="binary" \
+                                   ["postgresql"]="postgresql")
 
 SERIALIZER=${backend_serializer_map[$BACKEND]}
 
+# Set backend and serializer
 sed -i "s/backend=.*/backend=$BACKEND/" $CONF
 sed -i "s/serializer=.*/serializer=$SERIALIZER/" $CONF
 
+# Set PostgreSQL configurations if needed
+if [ "$BACKEND" == "postgresql" ]; then
+    sed -i "s/#jdbc.driver=.*/jdbc.driver=$POSTGRESQL_DRIVER/" $CONF
+    sed -i "s?#jdbc.url=.*?jdbc.url=$POSTGRESQL_URL?" $CONF
+    sed -i "s/#jdbc.username=.*/jdbc.username=$POSTGRESQL_USERNAME/" $CONF
+fi
+
 # Append schema.sync_deletion=true to config file
 echo "schema.sync_deletion=true" >> $CONF
 

hugegraph-dist/src/main/java/com/baidu/hugegraph/dist/RegisterUtil.java

@@ -52,7 +52,8 @@ public static void registerBackends() {
         String confFile = "/backend.properties";
         InputStream input = RegisterUtil.class.getClass()
                                         .getResourceAsStream(confFile);
-        E.checkState(input != null, "Can't read file '%s' as stream", confFile);
+        E.checkState(input != null,
+                     "Can't read file '%s' as stream", confFile);
 
         PropertiesConfiguration props = new PropertiesConfiguration();
         props.setDelimiterParsingDisabled(true);
@@ -89,8 +90,12 @@ private static void registerBackend(String backend) {
             case "palo":
                 registerPalo();
                 break;
+            case "postgresql":
+                registerPostgresql();
+                break;
             default:
-                throw new HugeException("Unsupported backend type '%s'", backend);
+                throw new HugeException("Unsupported backend type '%s'",
+                                        backend);
         }
     }
 
@@ -165,6 +170,18 @@ public static void registerPalo() {
                 "com.baidu.hugegraph.backend.store.palo.PaloStoreProvider");
     }
 
+    public static void registerPostgresql() {
+        // Register config
+        OptionSpace.register("postgresql",
+                "com.baidu.hugegraph.backend.store.postgresql.PostgresqlOptions");
+        // Register serializer
+        SerializerFactory.register("postgresql",
+                "com.baidu.hugegraph.backend.store.postgresql.PostgresqlSerializer");
+        // Register backend
+        BackendProviderFactory.register("postgresql",
+                "com.baidu.hugegraph.backend.store.postgresql.PostgresqlStoreProvider");
+    }
+
     public static void registerServer() {
         OptionSpace.register("server", "com.baidu.hugegraph.config.ServerOptions");
     }

hugegraph-dist/src/main/resources/backend.properties

@@ -1 +1 @@
-backends=[cassandra, scylladb, rocksdb, mysql, palo, hbase]
+backends=[cassandra, scylladb, rocksdb, mysql, palo, hbase, postgresql]

hugegraph-mysql/src/main/java/com/baidu/hugegraph/backend/store/mysql/MysqlOptions.java

@@ -27,7 +27,7 @@
 
 public class MysqlOptions extends OptionHolder {
 
-    private MysqlOptions() {
+    protected MysqlOptions() {
         super();
     }
 
@@ -89,4 +89,12 @@ public static synchronized MysqlOptions instance() {
                     rangeInt(1, 10),
                     3
             );
+
+    public static final ConfigOption<String> SSL_MODE =
+            new ConfigOption<>(
+                    "jdbc.ssl_mode",
+                    "The SSL mode of connections with database.",
+                    disallowEmpty(),
+                    "disable"
+            );
 }

hugegraph-mysql/src/main/java/com/baidu/hugegraph/backend/store/mysql/MysqlSerializer.java

@@ -162,4 +162,9 @@ protected void readUserdata(SchemaElement schema,
             schema.userdata(e.getKey(), e.getValue());
         }
     }
+
+    @Override
+    protected String escapeString(String value) {
+        return MysqlUtil.escapeString(value);
+    }
 }

hugegraph-mysql/src/main/java/com/baidu/hugegraph/backend/store/mysql/MysqlSessions.java

@@ -147,8 +147,11 @@ public void createDatabase() {
         try (Connection conn = this.openWithoutDB(0)) {
             conn.createStatement().execute(sql);
         } catch (SQLException e) {
-            throw new BackendException("Failed to create database '%s'",
-                                       this.database);
+            if (!e.getMessage().endsWith("already exists")) {
+                throw new BackendException("Failed to create database '%s'", e,
+                                           this.database);
+            }
+            // Ignore exception if database already exists
         }
     }
 
@@ -194,7 +197,7 @@ public boolean existsDatabase() {
     /**
      * Connect DB without specified database
      */
-    private Connection openWithoutDB(int timeout) {
+    protected Connection openWithoutDB(int timeout) {
         String jdbcUrl = this.config.get(MysqlOptions.JDBC_URL);
         String url = new URIBuilder().setPath(jdbcUrl)
                                      .setParameter("socketTimeout",

hugegraph-mysql/src/main/java/com/baidu/hugegraph/backend/store/mysql/MysqlStore.java

@@ -114,7 +114,8 @@ public synchronized void open(HugeConfig config) {
         try {
             this.sessions.open(config);
         } catch (Exception e) {
-            if (!e.getMessage().startsWith("Unknown database")) {
+            if (!e.getMessage().startsWith("Unknown database") &&
+                !e.getMessage().endsWith("does not exist")) {
                 throw new BackendException("Failed connect with mysql, " +
                                            "please ensure it's ok", e);
             }