Spring Boot配置MongoDB连接池

Spring Boot中通过依赖 spring-boot-starter-data-mongodb ，来实现 spring-data-mongodb 的自动配置。

但是默认情况下，Spring Boot 中，并没有像使用MySQL或者Redis一样，提供了连接池配置的功能。因此，我们需要自行重写 MongoDbFactory ，实现MongoDB客户端连接的参数配置扩展。

需要说明的是，MongoDB的客户端本身就是一个连接池，因此，我们只需要配置客户端即可。

配置文件

为了统一Spring Boot的配置，我们要将重写的配置也配置到 application.yml 中，前缀为 spring.data.mongodb.custom 下（前缀可自己随意配置）：

spring:
 data:
 mongodb:
  custom:
  hosts:
   - 10.0.5.1
   - 10.0.5.1
  ports:
   - 27017
   - 27018
  replica-set: mgset-3590061
  username: jancee
  password: abc123
  database: jancee
  authentication-database: admin
  connections-per-host: 20
  min-connections-per-host: 20

该配置例子中，配置了副本集，其中包含了主机 10.0.5.1:27017 和 10.0.5.1:27018 ，其它配置与Spring Boot的标准配置类似，另外， connections-per-host 为客户端的连接数， in-connections-per-host 为客户端最小连接数。

将配置包装成类

为方便调用和可读性，将上述配置包装成一个配置实体类， MongoConfig.java 代码如下:

package com.feidiao.jancee.fdiot.api.config.mongo;
import org.hibernate.validator.constraints.NotBlank;
import org.hibernate.validator.constraints.NotEmpty;
import org.springframework.stereotype.Component;
import org.springframework.validation.annotation.Validated;
import java.util.List;
 
@Component
@Validated
public class MongoSettingsProperties {
 
 @NotBlank
 private String database;
 
 @NotEmpty
 private List<String> hosts;
 
 @NotEmpty
 private List<Integer> ports;
 private String replicaSet;
 private String username;
 private String password;
 private String authenticationDatabase;
 private Integer minConnectionsPerHost = 10;
 private Integer connectionsPerHost = 2;
 public MongoSettingsProperties() {
 
 }
 
 public String getDatabase() {
  return database;
 }
 
 public void setDatabase(String database) {
  this.database = database;
 }
 
 public List<String> getHosts() {
  return hosts;
 }
 
 public void setHosts(List<String> hosts) {
  this.hosts = hosts;
 }
 
 public List<Integer> getPorts() {
  return ports;
 }
 
 public void setPorts(List<Integer> ports) {
  this.ports = ports;
 }
 
 public String getReplicaSet() {
  return replicaSet;
 }
 
 public void setReplicaSet(String replicaSet) {
  this.replicaSet = replicaSet;
 }
 
 public String getUsername() {
  return username;
 }
 
 public void setUsername(String username) {
  this.username = username;
 }
 
 public String getPassword() {
  return password;
 }
 
 public void setPassword(String password) {
  this.password = password;
 }
 
 public String getAuthenticationDatabase() {
  return authenticationDatabase;
 }
 
 public void setAuthenticationDatabase(String authenticationDatabase) {
  this.authenticationDatabase = authenticationDatabase;
 }
 
 public Integer getMinConnectionsPerHost() {
  return minConnectionsPerHost;
 }
 
 public void setMinConnectionsPerHost(Integer minConnectionsPerHost) {
  this.minConnectionsPerHost = minConnectionsPerHost;
 }
 
 public Integer getConnectionsPerHost() {
  return connectionsPerHost;
 }
 
 public void setConnectionsPerHost(Integer connectionsPerHost)  {
  this.connectionsPerHost = connectionsPerHost;
 }
}

覆盖MongoDbFactory

接下来，就是覆盖Spring Boot原有的 MongoDbFactory Bean，新建文件 MongoConfig.java ，代码如下：

import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.SimpleMongoDbFactory;
import java.util.ArrayList;
import java.util.List;
 
@Configuration
public class MongoConfig {
 // 注入配置实体
 @Autowired
 private MongoSettingsProperties mongoSettingsProperties;
 @Bean
 @ConfigurationProperties(
   prefix = "spring.data.mongodb.custom")
 MongoSettingsProperties mongoSettingsProperties() {
  return new MongoSettingsProperties();
 }
 
 // 覆盖默认的MongoDbFactory
 @Bean
 MongoDbFactory mongoDbFactory() {
  //客户端配置（连接数、副本集群验证）
  MongoClientOptions.Builder builder = new MongoClientOptions.Builder();
  builder.connectionsPerHost(mongoSettingsProperties.getConnectionsPerHost());
  builder.minConnectionsPerHost(mongoSettingsProperties.getMinConnectionsPerHost());
  if (mongoSettingsProperties.getReplicaSet() != null) {
   builder.requiredReplicaSetName(mongoSettingsProperties.getReplicaSet());
  }
  MongoClientOptions mongoClientOptions = builder.build();
 
  // MongoDB地址列表
  List<ServerAddress> serverAddresses = new ArrayList<>();
  for (String host : mongoSettingsProperties.getHosts()) {
   Integer index = mongoSettingsProperties.getHosts().indexOf(host);
   Integer port = mongoSettingsProperties.getPorts().get(index);
 
   ServerAddress serverAddress = new ServerAddress(host, port);
   serverAddresses.add(serverAddress);
  }
  System.out.println("serverAddresses:" + serverAddresses.toString());
 
  // 连接认证
  List<MongoCredential> mongoCredentialList = new ArrayList<>();
  if (mongoSettingsProperties.getUsername() != null) {
   mongoCredentialList.add(MongoCredential.createScramSha1Credential(
     mongoSettingsProperties.getUsername(),
     mongoSettingsProperties.getAuthenticationDatabase() != null ? mongoSettingsProperties.getAuthenticationDatabase() : mongoSettingsProperties.getDatabase(),
     mongoSettingsProperties.getPassword().toCharArray()));
  }
  System.out.println("mongoCredentialList:" + mongoCredentialList.toString());
  //创建客户端和Factory
  MongoClient mongoClient = new MongoClient(serverAddresses, mongoCredentialList, mongoClientOptions);
  MongoDbFactory mongoDbFactory = new SimpleMongoDbFactory(mongoClient, mongoSettingsProperties.getDatabase());
  return mongoDbFactory;
 }
}

在这里，实现了MongoDB连接时，前面配置的参数的设置，按照自己的实际情况，可以在 new SimpleMongoDbFactory 时，增加修改自己需要的配置参数。

至此，就完成了全部配置。

转载来源：http://blog.didispace.com/spring-boot-mongodb-connection-pool/