org.springframework.data.mongodb.core.ReflectiveDbInvoker.java Source code

Introduction

Here is the source code for org.springframework.data.mongodb.core.ReflectiveDbInvoker.java

Source

/*
 * Copyright 2015 the original author or authors.
 *
 * 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 org.springframework.data.mongodb.core;

import static org.springframework.data.mongodb.util.MongoClientVersion.*;
import static org.springframework.util.ReflectionUtils.*;

import java.lang.reflect.Method;

import org.springframework.data.authentication.UserCredentials;
import org.springframework.data.mongodb.CannotGetMongoDbConnectionException;
import org.springframework.data.mongodb.util.MongoClientVersion;

import com.mongodb.DB;
import com.mongodb.Mongo;

/**
 * {@link ReflectiveDbInvoker} provides reflective access to {@link DB} API that is not consistently available for
 * various driver versions.
 *
 * @author Christoph Strobl
 * @author Oliver Gierke
 * @since 1.7
 */
final class ReflectiveDbInvoker {

    private static final Method DB_IS_AUTHENTICATED_METHOD;
    private static final Method DB_AUTHENTICATE_METHOD;
    private static final Method DB_REQUEST_DONE_METHOD;
    private static final Method DB_ADD_USER_METHOD;
    private static final Method DB_REQUEST_START_METHOD;

    static {

        DB_IS_AUTHENTICATED_METHOD = findMethod(DB.class, "isAuthenticated");
        DB_AUTHENTICATE_METHOD = findMethod(DB.class, "authenticate", String.class, char[].class);
        DB_REQUEST_DONE_METHOD = findMethod(DB.class, "requestDone");
        DB_ADD_USER_METHOD = findMethod(DB.class, "addUser", String.class, char[].class);
        DB_REQUEST_START_METHOD = findMethod(DB.class, "requestStart");
    }

    private ReflectiveDbInvoker() {
    }

    /**
     * Authenticate against database using provided credentials in case of a MongoDB Java driver version 2.
     *
     * @param mongo must not be {@literal null}.
     * @param db must not be {@literal null}.
     * @param credentials must not be {@literal null}.
     * @param authenticationDatabaseName
     */
    public static void authenticate(Mongo mongo, DB db, UserCredentials credentials,
            String authenticationDatabaseName) {

        String databaseName = db.getName();

        DB authDb = databaseName.equals(authenticationDatabaseName) ? db : mongo.getDB(authenticationDatabaseName);

        synchronized (authDb) {

            Boolean isAuthenticated = (Boolean) invokeMethod(DB_IS_AUTHENTICATED_METHOD, authDb);
            if (!isAuthenticated) {

                String username = credentials.getUsername();
                String password = credentials.hasPassword() ? credentials.getPassword() : null;

                Boolean authenticated = (Boolean) invokeMethod(DB_AUTHENTICATE_METHOD, authDb, username,
                        password == null ? null : password.toCharArray());
                if (!authenticated) {
                    throw new CannotGetMongoDbConnectionException(
                            "Failed to authenticate to database [" + databaseName + "], " + credentials.toString(),
                            databaseName, credentials);
                }
            }
        }
    }

    /**
     * Starts a new 'consistent request' in case of MongoDB Java driver version 2. Will do nothing for MongoDB Java driver
     * version 3 since the operation is no longer available.
     *
     * @param db
     */
    public static void requestStart(DB db) {

        if (isMongo3Driver()) {
            return;
        }

        invokeMethod(DB_REQUEST_START_METHOD, db);
    }

    /**
     * Ends the current 'consistent request'. a new 'consistent request' in case of MongoDB Java driver version 2. Will do
     * nothing for MongoDB Java driver version 3 since the operation is no longer available
     *
     * @param db
     */
    public static void requestDone(DB db) {

        if (MongoClientVersion.isMongo3Driver()) {
            return;
        }

        invokeMethod(DB_REQUEST_DONE_METHOD, db);
    }

    /**
     * @param db
     * @param username
     * @param password
     * @throws UnsupportedOperationException
     */
    public static void addUser(DB db, String username, char[] password) {

        if (isMongo3Driver()) {
            throw new UnsupportedOperationException(
                    "Please use DB.command() to call either the createUser or updateUser command!");
        }

        invokeMethod(DB_ADD_USER_METHOD, db, username, password);
    }
}