Datax MongoDBReader

  • 2021-02-02
  • 浏览 (74)

Datax MongoDBReader

1 快速介绍

MongoDBReader 插件利用 MongoDB 的java客户端MongoClient进行MongoDB的读操作。最新版本的Mongo已经将DB锁的粒度从DB级别降低到document级别,配合上MongoDB强大的索引功能,基本可以达到高性能的读取MongoDB的需求。

2 实现原理

MongoDBReader通过Datax框架从MongoDB并行的读取数据,通过主控的JOB程序按照指定的规则对MongoDB中的数据进行分片,并行读取,然后将MongoDB支持的类型通过逐一判断转换成Datax支持的类型。

3 功能说明

  • 该示例从ODPS读一份数据到MongoDB。

    {
    "job": {
        "setting": {
            "speed": {
                "channel": 2
            }
        },
        "content": [
            {
                "reader": {
                    "name": "mongodbreader",
                    "parameter": {
                        "address": ["127.0.0.1:27017"],
                        "userName": "",
                        "userPassword": "",
                        "dbName": "tag_per_data",
                        "collectionName": "tag_data12",
                        "column": [
                            {
                                "name": "unique_id",
                                "type": "string"
                            },
                            {
                                "name": "sid",
                                "type": "string"
                            },
                            {
                                "name": "user_id",
                                "type": "string"
                            },
                            {
                                "name": "auction_id",
                                "type": "string"
                            },
                            {
                                "name": "content_type",
                                "type": "string"
                            },
                            {
                                "name": "pool_type",
                                "type": "string"
                            },
                            {
                                "name": "frontcat_id",
                                "type": "Array",
                                "spliter": ""
                            },
                            {
                                "name": "categoryid",
                                "type": "Array",
                                "spliter": ""
                            },
                            {
                                "name": "gmt_create",
                                "type": "string"
                            },
                            {
                                "name": "taglist",
                                "type": "Array",
                                "spliter": " "
                            },
                            {
                                "name": "property",
                                "type": "string"
                            },
                            {
                                "name": "scorea",
                                "type": "int"
                            },
                            {
                                "name": "scoreb",
                                "type": "int"
                            },
                            {
                                "name": "scorec",
                                "type": "int"
                            }
                        ]
                    }
                },
                "writer": {
                    "name": "odpswriter",
                    "parameter": {
                        "project": "tb_ai_recommendation",
                        "table": "jianying_tag_datax_read_test01",
                        "column": [
                            "unique_id",
                            "sid",
                            "user_id",
                            "auction_id",
                            "content_type",
                            "pool_type",
                            "frontcat_id",
                            "categoryid",
                            "gmt_create",
                            "taglist",
                            "property",
                            "scorea",
                            "scoreb"
                        ],
                        "accessId": "**************",
                        "accessKey": "********************",
                        "truncate": true,
                        "odpsServer": "xxx/api",
                        "tunnelServer": "xxx",
                        "accountType": "aliyun"
                    }
                }
            }
        ]
    }
    }
    

    4 参数说明

  • address: MongoDB的数据地址信息,因为MonogDB可能是个集群,则ip端口信息需要以Json数组的形式给出。【必填】

  • userName:MongoDB的用户名。【选填】

  • userPassword: MongoDB的密码。【选填】

  • collectionName: MonogoDB的集合名。【必填】

  • column:MongoDB的文档列名。【必填】

  • name:Column的名字。【必填】

  • type:Column的类型。【选填】

  • splitter:因为MongoDB支持数组类型,但是Datax框架本身不支持数组类型,所以mongoDB读出来的数组类型要通过这个分隔符合并成字符串。【选填】

  • query: MongoDB的额外查询条件。【选填】

5 类型转换

DataX 内部类型 MongoDB 数据类型
Long int, Long
Double double
String string, array
Date date
Boolean boolean
Bytes bytes

6 性能报告

7 测试报告