java - 数据管道的前提条件

Question

我在 json 脚本上做了一些活动。需要在其上添加前提条件。如何在 json 脚本上使用前置条件。

在前提条件下，我需要检查 mysql db 字段。一旦标记为'Y'，开始执行否则应该停止执行。

Answer 1

您可以为此使用 ShellCommandPrecondition，它可以让您编写自定义前提条件。

{
  "objects": [
    {
      "schedule": {
        "ref": "DefaultSchedule"
      },
      "resourceRole": "DataPipelineDefaultResourceRole",
      "role": "DataPipelineDefaultRole",
      "name": "DefaultResource1",
      "id": "ResourceId_dWoZ0",
      "type": "Ec2Resource",
      "terminateAfter": "1 Hour"
    },
    {
      "name": "DefaultPrecondition1",
      "id": "PreconditionId_yA2rV",
      "type": "ShellCommandPrecondition",
      "command": "<Script to check mysql field>"
    },
    {
      "occurrences": "1",
      "period": "1 Day",
      "name": "RunOnce",
      "id": "DefaultSchedule",
      "type": "Schedule",
      "startAt": "FIRST_ACTIVATION_DATE_TIME"
    },
    {
      "failureAndRerunMode": "CASCADE",
      "schedule": {
        "ref": "DefaultSchedule"
      },
      "resourceRole": "DataPipelineDefaultResourceRole",
      "role": "DataPipelineDefaultRole",
      "pipelineLogUri": "s3://<mybucket>",
      "scheduleType": "cron",
      "name": "Default",
      "id": "Default"
    },
    {
      "schedule": {
        "ref": "DefaultSchedule"
      },
      "name": "DefaultActivity1",
      "runsOn": {
        "ref": "ResourceId_dWoZ0"
      },
      "precondition": {
        "ref": "PreconditionId_yA2rV"
      },
      "id": "ActivityId_gmQ0W",
      "type": "ShellCommandActivity",
      "command": "echo 'Hello world'"
    }
  ],
  "parameters": []
}