Add generic JDBC data source connector

BaseJdbcConfig.java

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+/*
+ * 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 io.prestosql.plugin.jdbc;
+
+import com.google.common.base.Splitter;
+import com.google.common.collect.ImmutableSet;
+import io.airlift.configuration.Config;
+import io.airlift.configuration.ConfigDescription;
+import io.airlift.units.Duration;
+import io.airlift.units.MinDuration;
+
+import javax.validation.constraints.NotNull;
+
+import java.util.Set;
+
+import static com.google.common.base.Strings.nullToEmpty;
+import static java.util.concurrent.TimeUnit.MINUTES;
+
+public class BaseJdbcConfig
+{
+    private String connectionUrl;
+    private boolean caseInsensitiveNameMatching;
+    private Duration caseInsensitiveNameMatchingCacheTtl = new Duration(1, MINUTES);
+    private Set<String> jdbcTypesMappedToVarchar = ImmutableSet.of();
+    private Duration metadataCacheTtl = new Duration(0, MINUTES);
+    private boolean cacheMissing;
+    private String driverClass;
+
+    @NotNull
+    public String getConnectionUrl()
+    {
+        return connectionUrl;
+    }
+
+    @Config("connection-url")
+    public BaseJdbcConfig setConnectionUrl(String connectionUrl)
+    {
+        this.connectionUrl = connectionUrl;
+        return this;
+    }
+
+    public String getDriverClass()
+    {
+        return driverClass;
+    }
+
+    @Config("driver-class")
+    public BaseJdbcConfig setDriverClass(String driverClass)
+    {
+        this.driverClass = driverClass;
+        return this;
+    }
+
+    public boolean isCaseInsensitiveNameMatching()
+    {
+        return caseInsensitiveNameMatching;
+    }
+
+    @Config("case-insensitive-name-matching")
+    public BaseJdbcConfig setCaseInsensitiveNameMatching(boolean caseInsensitiveNameMatching)
+    {
+        this.caseInsensitiveNameMatching = caseInsensitiveNameMatching;
+        return this;
+    }
+
+    @NotNull
+    @MinDuration("0ms")
+    public Duration getCaseInsensitiveNameMatchingCacheTtl()
+    {
+        return caseInsensitiveNameMatchingCacheTtl;
+    }
+
+    @Config("case-insensitive-name-matching.cache-ttl")
+    public BaseJdbcConfig setCaseInsensitiveNameMatchingCacheTtl(Duration caseInsensitiveNameMatchingCacheTtl)
+    {
+        this.caseInsensitiveNameMatchingCacheTtl = caseInsensitiveNameMatchingCacheTtl;
+        return this;
+    }
+
+    public Set<String> getJdbcTypesMappedToVarchar()
+    {
+        return jdbcTypesMappedToVarchar;
+    }
+
+    @Config("jdbc-types-mapped-to-varchar")
+    public BaseJdbcConfig setJdbcTypesMappedToVarchar(String jdbcTypesMappedToVarchar)
+    {
+        this.jdbcTypesMappedToVarchar = ImmutableSet.copyOf(Splitter.on(",").omitEmptyStrings().trimResults().split(nullToEmpty(jdbcTypesMappedToVarchar)));
+        return this;
+    }
+
+    @NotNull
+    @MinDuration("0ms")
+    public Duration getMetadataCacheTtl()
+    {
+        return metadataCacheTtl;
+    }
+
+    @Config("metadata.cache-ttl")
+    @ConfigDescription("Determines how long meta information will be cached")
+    public BaseJdbcConfig setMetadataCacheTtl(Duration metadataCacheTtl)
+    {
+        this.metadataCacheTtl = metadataCacheTtl;
+        return this;
+    }
+
+    public boolean isCacheMissing()
+    {
+        return cacheMissing;
+    }
+
+    @Config("metadata.cache-missing")
+    @ConfigDescription("Determines if missing information will be cached")
+    public BaseJdbcConfig setCacheMissing(boolean cacheMissing)
+    {
+        this.cacheMissing = cacheMissing;
+        return this;
+    }
+}

GenericJdbcClient.java

@@ -0,0 +1,148 @@
+/*
+ * 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 io.prestosql.plugin.genericjdbc;
+
+import com.google.common.base.Joiner;
+import io.prestosql.plugin.jdbc.BaseJdbcClient;
+import io.prestosql.plugin.jdbc.BaseJdbcConfig;
+import io.prestosql.plugin.jdbc.ColumnMapping;
+import io.prestosql.plugin.jdbc.ConnectionFactory;
+import io.prestosql.plugin.jdbc.JdbcTypeHandle;
+import io.prestosql.plugin.jdbc.WriteMapping;
+import io.prestosql.spi.connector.ConnectorSession;
+import io.prestosql.spi.predicate.Domain;
+import io.prestosql.spi.type.CharType;
+import io.prestosql.spi.type.Type;
+import io.prestosql.spi.type.VarcharType;
+
+import javax.inject.Inject;
+
+import java.sql.Connection;
+import java.util.List;
+import java.util.Optional;
+import java.util.function.UnaryOperator;
+
+import static io.prestosql.plugin.jdbc.PredicatePushdownController.DISABLE_PUSHDOWN;
+import static io.prestosql.plugin.jdbc.StandardColumnMappings.booleanWriteFunction;
+import static io.prestosql.plugin.jdbc.StandardColumnMappings.charWriteFunction;
+import static io.prestosql.plugin.jdbc.StandardColumnMappings.varcharWriteFunction;
+import static io.prestosql.spi.type.BooleanType.BOOLEAN;
+import static java.lang.String.format;
+import static java.util.stream.Collectors.joining;
+
+public class GenericJdbcClient
+        extends BaseJdbcClient
+{
+    private static final Joiner DOT_JOINER = Joiner.on(".");
+
+    // Sybase supports 2100 parameters in prepared statement, let's create a space for about 4 big IN predicates
+    private static final int MAX_LIST_EXPRESSIONS = 500;
+
+    // TODO improve this by calling Domain#simplify
+    private static final UnaryOperator<Domain> DISABLE_UNSUPPORTED_PUSHDOWN = domain -> {
+        if (domain.getValues().getRanges().getRangeCount() <= MAX_LIST_EXPRESSIONS) {
+            return domain;
+        }
+        return Domain.all(domain.getType());
+    };
+
+    //not sure if getIdentifierQuoteString from jdbc driver is accurate instead...
+    @Inject
+    public GenericJdbcClient(BaseJdbcConfig config, ConnectionFactory connectionFactory)
+    {
+        super(config, (config.getConnectionUrl().startsWith("jdbc:impala") || config.getConnectionUrl().startsWith("jdbc:hive2") || config.getConnectionUrl().startsWith("jdbc:mysql")) ? "`" : "\"", connectionFactory);
+    }
+
+    protected void copyTableSchema(Connection connection, String catalogName, String schemaName, String tableName, String newTableName, List<String> columnNames)
+    {
+        String sql = format(
+                "SELECT %s INTO %s FROM %s WHERE 0 = 1",
+                columnNames.stream()
+                        .map(this::quoted)
+                        .collect(joining(", ")),
+                quoted(catalogName, schemaName, newTableName),
+                quoted(catalogName, schemaName, tableName));
+        execute(connection, sql);
+    }
+
+    @Override
+    public Optional<ColumnMapping> toPrestoType(ConnectorSession session, Connection connection, JdbcTypeHandle typeHandle)
+    {
+        try {
+            if (connection.getMetaData().getURL() != null && connection.getMetaData().getURL().startsWith("jdbc:impala") && (typeHandle.toString().contains("jdbcTypeName=ARRAY") || typeHandle.toString().contains("jdbcTypeName=MAP") || typeHandle.toString().contains("jdbcTypeName=STRUCT"))) {
+                return Optional.empty();
+            }
+        }
+        catch (Exception e) {
+            //not all drivers have getURL...like SparkThrift
+        }
+
+        Optional<ColumnMapping> mapping = getForcedMappingToVarchar(typeHandle);
+        if (mapping.isPresent()) {
+            return mapping;
+        }
+        // TODO implement proper type mapping
+        return super.toPrestoType(session, connection, typeHandle)
+                .map(columnMapping -> new ColumnMapping(
+                        columnMapping.getType(),
+                        columnMapping.getReadFunction(),
+                        columnMapping.getWriteFunction(),
+                        DISABLE_PUSHDOWN));
+    }
+
+    @Override
+    public WriteMapping toWriteMapping(ConnectorSession session, Type type)
+    {
+        if (type == BOOLEAN) {
+            return WriteMapping.booleanMapping("bit", booleanWriteFunction());
+        }
+
+        if (type instanceof VarcharType) {
+            VarcharType varcharType = (VarcharType) type;
+            String dataType;
+            if (varcharType.isUnbounded() || varcharType.getBoundedLength() > 4000) {
+                dataType = "nvarchar(max)";
+            }
+            else {
+                dataType = "nvarchar(" + varcharType.getBoundedLength() + ")";
+            }
+            return WriteMapping.sliceMapping(dataType, varcharWriteFunction());
+        }
+
+        if (type instanceof CharType) {
+            CharType charType = (CharType) type;
+            String dataType;
+            if (charType.getLength() > 4000) {
+                dataType = "nvarchar(max)";
+            }
+            else {
+                dataType = "nchar(" + charType.getLength() + ")";
+            }
+            return WriteMapping.sliceMapping(dataType, charWriteFunction());
+        }
+
+        // TODO implement proper type mapping
+        return super.toWriteMapping(session, type);
+    }
+
+    private static String singleQuote(String... objects)
+    {
+        return singleQuote(DOT_JOINER.join(objects));
+    }
+
+    private static String singleQuote(String literal)
+    {
+        return "\'" + literal + "\'";
+    }
+}