es 7.x 进阶 文档冲突

文档冲突

并发运行时的数据控制. 悲观锁: 假设有冲突发送, 阻塞资源的访问, 只有一个线程对其修改 乐观锁: 不会阻塞正在尝试的操作, 使用版本号, 只有当前最新的版本号或者大于当前版本号才能修改成功, 程序可以自行决定如何解决冲突, 例如重试更新, 使用新的数据等.

版本号的实战 : 创建文档 : 创建一个shopping 的索引 put请求 http://127.0.0.1:9200/shopping1

创建文档 put请求 http://127.0.0.1:9200/shopping1/_create/1001

请求体 :

{
    "title": "华为手机",
    "category": "华为",
    "images": "http://huawei.com",
    "price": 1999.00
}

响应 :

{
    "_index": "shopping1",
    "_type": "_doc",
    "_id": "1001",
    "_version": 1,
    "result": "created",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 1,
    "_primary_term": 1
}

执行修改 post请求 http://127.0.0.1:9200/shopping1/_update/1001 请求体如下 :

{
    "doc": {
        "name": "华为1"
    }
}

得到的响应:

{
    "_index": "shopping1",
    "_type": "_doc",
    "_id": "1001",
    "_version": 2,
    "result": "updated",
    "_shards": {
        "total": 2,
        "successful": 1,
        "failed": 0
    },
    "_seq_no": 2,
    "_primary_term": 1
}

加版本号的更新, 请求url如下 http://127.0.0.1:9200/shopping1/_update/1001?version=1 得到的响应如下

{
    "error": {
        "root_cause": [
            {
                "type": "action_request_validation_exception",
                "reason": "Validation Failed: 1: internal versioning can not be used for optimistic concurrency control. Please use `if_seq_no` and `if_primary_term` instead;"
            }
        ],
        "type": "action_request_validation_exception",
        "reason": "Validation Failed: 1: internal versioning can not be used for optimistic concurrency control. Please use `if_seq_no` and `if_primary_term` instead;"
    },
    "status": 400
}

最新的es不用version, 更换url http://127.0.0.1:9200/shopping1/_update/1001?if_seq_no=1&if_primary_term=0 得到的响应如下 :

{
    "error": {
        "root_cause": [
            {
                "type": "action_request_validation_exception",
                "reason": "Validation Failed: 1: ifSeqNo is set, but primary term is [0];"
            }
        ],
        "type": "action_request_validation_exception",
        "reason": "Validation Failed: 1: ifSeqNo is set, but primary term is [0];"
    },
    "status": 400
}

查询最新的数据的版本 : get请求 http://127.0.0.1:9200/shopping1/_doc/1001 响应如下 : seq为2 , term是1

因此使用如下的post请求去修改 http://127.0.0.1:9200/shopping1/_update/1001?if_seq_no=2&if_primary_term=1 响应如下

{
    "_index": "shopping1",
    "_type": "_doc",
    "_id": "1001",
    "_version": 2,
    "result": "noop",
    "_shards": {
        "total": 0,
        "successful": 0,
        "failed": 0
    },
    "_seq_no": 2,
    "_primary_term": 1
}

外部系统版本控制

es可以使用 version_type = external 的外部版本号的配置. 测试: 当前的数据信息如下 : 发送post请求. 指定版本为外部的版本信息. http://127.0.0.1:9200/shopping1/_doc/1001?version=1&version_type=external 此时报错如下

{
    "error": {
        "root_cause": [
            {
                "type": "version_conflict_engine_exception",
                "reason": "[1001]: version conflict, current version [3] is higher or equal to the one provided [1]",
                "index_uuid": "ey7CVOhYRwKVFbImn2XNKg",
                "shard": "0",
                "index": "shopping1"
            }
        ],
        "type": "version_conflict_engine_exception",
        "reason": "[1001]: version conflict, current version [3] is higher or equal to the one provided [1]",
        "index_uuid": "ey7CVOhYRwKVFbImn2XNKg",
        "shard": "0",
        "index": "shopping1"
    },
    "status": 409
}

提示版本冲突, 当前版本是3 , 使用的版本是1 . 必须要比当前版本高才行.

发送post请求 http://127.0.0.1:9200/shopping1/_doc/1001?version=4&version_type=external 请求体:

{
    "doc": {
        "name": "华为22222"
    }
}