Make the tasks in the scheduled task XXL job flexible

It is a common requirement to use scheduled tasks for business compensation in projects . For a mission , We often fix the start time or end time in the code . If a scheduled task misses data . such as ：

• Timing task ： Inquire about 1 Days ago to the current system time
• Missing data ： stay 3 A few days ago, some data has not been executed yet

If you do not set the start time to a dynamic variable, this problem cannot be solved . You can configure the start time in the registry , The query time is ：3 Days ago, ~ Current system time . This SQL The query system is relatively low .

Another way is to set the start time and end time as variables in the registry , In this way, you can dynamically customize the start and end times of your task query .

But the task parameter is configured in the registry ？ It's better to configure it in the task ？ I personally prefer the latter . The reasons are as follows ：

• Use the configuration center to configure , Each task is configured with different variables , The amount of code added is not very elegant
• Use the dynamic parameter configuration in the task , In this way, modifying the execution logic of a task is the closest to the task , Nearby principle .

So for scheduled tasks , We need to customize the following parameters ：

• Parameters 1： Business number ： The highest priority , It is possible that a piece of data was missed during the execution of the previous scheduled task . This is the time , how xxl job The task parameter of passed the business number . Then only execute this business number
• Parameters 2： Number of queries per page ： When performing scheduled tasks , If the time range of our inquiry is too wide , There may also be a lot of data , So we introduce the concept of paging to query data , Only query 1 Page and the number of queries can be configured .
• Parameters 3： Query start time ： A scheduled task is the data that needs to be operated on for a period of time , So there is a start time .
• Parameters 4： Query end time ： A scheduled task is the data that needs to be operated on for a period of time , So there is an end time .

When performing scheduled tasks , Or only Parameters 1 Otherwise, it would be Parameters 2、3、4. That is, either execute a specific piece of data or execute for a certain period of time, and the maximum number of pieces is Parameters 2 Value .

For the above 4 Parameters can be customized , Then request parameter settings ：

JobParamModel.java

public class JobParamModel {
    
 
    /**  Reference number , The order field can be understood as the order number  */
    private String referenceNo;
 
    /**  Base time ( End time ) yyyy-MM-dd HH:mm:ss */
    private String basicTime;
 
    /**  Forward offset  */
    private Integer forwardOffset;
 
    /**  Offset units forward  */
    private String forwardOffsetUnit;
 
    /**  Backward offset  */
    private Integer backwardOffset;
 
    /**  Shift back units  */
    private String backwardOffsetUnit;
 
    /**  Whether it is a fully closed interval time period  */
    private boolean wholeClosedRange;
 
    /**  paged  */
    private int pageSize = 500;
 
}

Let's analyze the function of each parameter .

• referenceNo： Reference number , The order field can be understood as the order number ： Like your scheduled tasks , Only one order number is required for execution . Then you only need to configure this parameter . It should have the highest priority .
• basicTime： Base time , That is our end time , This time can be set by yourself , If the reference time is not set , By default, the current system time is used as the base time
• forwardOffset： Forward offset , Obtain the start time of scheduled task execution based on the reference time , And forwardOffsetUnit In combination with . It means that the reference time is shifted forward by multiple time units ( At present, we support ： second (SECONDS)、 branch (MINUTES)、 when (HOURS)、 God (DAYS)). For example, the benchmark time is :2021-05-19 13:00:01 , The offset is 10 , Then the forward offset unit is hour (HOURS), The start time of the query is ： 2021-05-19 03:00:01. If not configured , The default start time is the base time minus 24 Hours , That is to query the data of the latest day .
• forwardOffsetUnit： Offset units forward , At present, we support ： second (SECONDS)、 branch (MINUTES)、 when (HOURS)、 God (DAYS)
• backwardOffset： Backward offset , Obtain the end time of scheduled task execution based on the reference time , And backwardOffsetUnit In combination with . It means that the reference time is shifted back by multiple time units ( At present, we support ： second (SECONDS)、 branch (MINUTES)、 when (HOURS)、 God (DAYS)). For example, the benchmark time is ：2021-05-19 13:00:01, The offset is -5, Then shift back in days (DAYS), The end time of the query is ：2021-05-14 13:00:01. If it is not configured, the default end time is the base time .
• backwardOffsetUnit： Shift back units , At present, we support ： second (SECONDS)、 branch (MINUTES)、 when (HOURS)、 God (DAYS)
• wholeClosedRange： Whether it is a fully closed interval time period , It means to set the start time to the current day 00:00:00, Set the end time to 23:59:59. such as wholeClosedRange by false The time period is : 2021-05-18 13:00:01 ~ 2021-05-19 13:00:01 . When the value is set to true when , The query period is ：2021-05-18 00:00:00 ~ 2021-05-19 23:59:59
• pageSize： Number of queries , Default query 500 strip , You can pass in the parameter of the scheduled task or the customized query number in the query criteria .

Be careful ： If the parameters passed by the scheduled task are illegal, the latest will be queried by default 1 Days of 500 Data .

Illustrate with examples ：

situation 1：{“basicTime” : “2021-05-19 13:00:00”, “forwardOffset” : 5, “forwardOffsetUnit” : “HOURS”}

Query criteria ： 2021-05-19 08:00:00 ~ 2021-05-19 13:00:00( The system time does not affect the query criteria )

situation 2：{“forwardOffset” : 5, “forwardOffsetUnit” : “HOURS”} system time :2021-06-30 20:59:11

Query criteria ：2021-06-30 15:59:11 ~ 2021-06-30 20:59:11( System time affects query criteria )

situation 3：{“forwardOffset” : 5, “forwardOffsetUnit” : “DAYS”, “backwardOffset”: -2, “backwardOffsetUnit”:“HOURS”} system time :2021-06-30 20:59:11

Query criteria ：2021-06-25 20:59:11 ~ 2021-06-30 18:59:11( System time affects query criteria )

situation 4：{“forwardOffset” : 5, “forwardOffsetUnit” : “DAYS”, “backwardOffset”: -2, “backwardOffsetUnit”:“HOURS”, “wholeClosedRange”} system time :2021-06-30 20:59:11

Query criteria ：2021-06-25 00:00:00 ~ 2021-06-30 23:59:59( System time affects query criteria )

This paper only provides a way of thinking , The implementation method is actually quite simple .