使用 Mongock 和 Spring Boot 进行数据库迁移

Question

我有课

@Data
@NoArgsConstructor
@AllArgsConstructor
@Document("animal")
public class Animal {
    private String id;
    private boolean isBirthYear;
}

我想将课程更新为：

@Data
@NoArgsConstructor
@AllArgsConstructor
@Document("animal")
public class Animal {
    private String id;
    private long isBirthYear;
}

不关心代码约定。我想编写一个迁移来将 mongodb 中的数据从布尔型转换为长型。

我尝试创建一个新班级

@Data
@NoArgsConstructor
@AllArgsConstructor
@Document("animal")
public class AnimalV2 {
    private String id;
    private long isBirthYear;
}

但我认为这不是一个好的解决方案。

Answer 1

import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import org.bson.Document;

public class AnimalMigration {

    public static void main(String[] args) {
        try (var mongoClient = MongoClients.create("your-mongodb-connection-string")) {
            var database = mongoClient.getDatabase("your-database-name");
            var collection = database.getCollection("animal");

            // Get all documents in the collection
            try (var cursor = collection.find().iterator()) {
                while (cursor.hasNext()) {
                    var document = cursor.next();

                    // Convert boolean to long for the isBirthYear field
                    if (document.containsKey("isBirthYear")) {
                        var isBirthYear = document.getBoolean("isBirthYear");
                        document.put("isBirthYear", isBirthYear ? 1L : 0L);
                    }

                    // Save the updated document back to the collection
                    collection.replaceOne(new Document("_id", document.getObjectId("_id")), document);
                }
            }
        }
    }
}