了解神功快照概念

Question

我有查询和执行计划，我想利用该快照这样我就可以在接收端恢复并重新开始执行它。

1. 什么格式应该发送到接收器？
2. 如何在接收端恢复？

以下是一些代码，我从西提仓库取。

SiddhiManager siddhiManager = new SiddhiManager(); 
    String query = 
      "define stream inStream(meta_roomNumber int,meta_temperature double);" + 
        "from inStream#window(10)[meta_temperature > 50]\n" + 
        "select *" + 
        "insert into outStream;"; 

    ExecutionPlanRuntime executionPlanRuntime = siddhiManager.createExecutionPlanRuntime(query); 

    executionPlanRuntime.start(); 
    SiddhiContext siddhicontext = new SiddhiContext(); 

    context.setSiddhiContext(siddhicontext); 
    context.setSnapshotService(new SnapshotService(context)); 
    executionPlanRuntime.snapshot(); 

Answer 1

您可以使用PersistenceStore来保存执行计划的状态（快照）并稍后恢复。请参考以下PersistenceTestCase以获取有关如何使用的。即;

// Create executionPlanRuntime 
    ExecutionPlanRuntime executionPlanRuntime = siddhiManager.createExecutionPlanRuntime(executionPlan); 

    // Register Callbacks, InputHandlers 
    executionPlanRuntime.addCallback("query1", queryCallback); 
    stream1 = executionPlanRuntime.getInputHandler("Stream1"); 

    // Start executionPlanRuntime 
    executionPlanRuntime.start(); 

    // Send events 
    stream1.send(new Object[]{"WSO2", 25.6f, 100}); 
    Thread.sleep(100); 
    stream1.send(new Object[]{"GOOG", 47.6f, 100}); 
    Thread.sleep(100); 

    // Persist the state 
    executionPlanRuntime.persist(); 

    // Shutdown the running execution plan 
    executionPlanRuntime.shutdown(); 

    // Create new executionPlanRuntime 
    executionPlanRuntime = siddhiManager.createExecutionPlanRuntime(executionPlan); 

    // Register Callbacks, InputHandlers 
    executionPlanRuntime.addCallback("query1", queryCallback); 
    stream1 = executionPlanRuntime.getInputHandler("Stream1"); 

    // Start executionPlanRuntime 
    executionPlanRuntime.start(); 

    // Restore to previously persisted state 
    executionPlanRuntime.restoreLastRevision();