What is workflow scheduling?

The execution of a workflow can be triggered by using the CloudFlow console or by invoking an SDK. The execution of a workflow can also be triggered by an event source. You can create workflow scheduling in a workflow. Workflow scheduling describes a set of rules. When an event meets these rules, the event source triggers the associated workflow. This topic describes what is workflow scheduling.

Workflow scheduling (a trigger) is a method to trigger a workflow. In an event-driven computing model, event sources are event producers and workflows are event handlers. Workflow scheduling provides a centralized and unified way to manage different event sources. In an event source, when an event that meets the rules defined by the workflow scheduling occurs, the event source automatically invokes the workflow that is associated with the workflow scheduling.

Sample scenarios

Example 1: The status change of an image in an Object Storage Service (OSS) bucket triggers the execution of the workflow.
You can invoke a workflow to download the image for processing, and store the processing result in OSS or other services. If OSS can focus on images that are recently uploaded and automatically invoke the associated workflow, you no longer need to invoke the workflow. This simplifies the development and use process.
OSS workflow scheduling focuses on these events and invokes the associated workflow. After you configure OSS workflow scheduling, the OSS workflow scheduling automatically triggers the workflow to download and process the image if a new image is uploaded.
Example 2: A log update in Simple Log Service (SLS) triggers the execution of the workflow.
You can invoke a workflow to query and analyze incremental logs. If SLS can focus on updated logs and automatically invoke the associated workflow, you do not need to invoke the workflow.
Simple Log Service workflow scheduling focuses on these events and invokes the associated workflow. After you configure Simple Log Service workflow scheduling, the Simple Log Service workflow scheduling automatically triggers the associated workflow to consume incremental logs when logs are updated.
Example 3: The workflow is triggered at the specified time.
For example, an application needs to collect data every 1 hour. You can invoke the associated workflow to collect and process data every hour. If the workflow can be automatically executed every hour, you no longer need to focus on time.
Time-based scheduling focuses on time events and invokes the associated workflow. After you configure time-based scheduling, the time-based scheduling automatically triggers the associated workflow to collect and process data at the specified time.

Scheduling type

The following scheduling type based on the integration method is supported by workflow:

Two-way integration scheduling: You can configure scheduling in the workflow and event source.
Event scheduling of cloud services: You can configure scheduling in the workflow and create workflow trigger rules in EventBridge. You do not need to configure scheduling in the event source.

The scheduling type supported by workflows includes synchronous invocation scheduling and asynchronous invocation scheduling based on workflow invocation methods. The workflow invocation methods have the following difference:

Synchronous invocation: Results are directly returned after events are processed by workflows.
Asynchronous invocation: Results are returned after events are written to internal queues of workflows. The workflow system ensures that the messages can be processed.

Two-way integration scheduling

Scheduling name	Workflow invocation method in standard mode	Workflow invocation method in express mode
Time-based scheduling	Asynchronous invocation	Synchronous invocation
Simple Log Service workflow scheduling	Asynchronous invocation	Synchronous invocation
MNS workflow scheduling	Asynchronous invocation	Synchronous invocation
Kafka workflow scheduling	Asynchronous invocation	Synchronous invocation
RocketMQ workflow scheduling	Asynchronous invocation	Synchronous invocation
RabbitMQ workflow scheduling	Asynchronous invocation	Synchronous invocation
HTTP workflow scheduling	Asynchronous invocation	Synchronous invocation

Event scheduling of cloud services

Scheduling name	Workflow invocation method in standard mode	Workflow invocation method in express mode
Alibaba Cloud service event scheduling	Asynchronous invocation	Synchronous invocation

Event syntax of workflow scheduling

The event syntax that is passed to the workflow interface varies based on the scheduling name. The following sections describe the event syntaxes of different scheduling names.

In an event that triggers workflow scheduling, you must use an expression to extract the Event parameter that is passed to the workflow. After you extract the Event parameter, you can use the Event parameter. For more information, see Inputs and outputs.

Time-based scheduling

{
    "datacontenttype":"application/json;charset=utf-8",
    "aliyunaccountid":"143998900779****",
    "aliyunpublishtime":"2022-09-21T05:00:00.035Z",
    "data":{
        "TimeZone":"GMT+0:00",
        "Schedule":"0/30 * * * * ?",
        "UserData":{
            "key":"value"
        }
    },
    "specversion":"1.0",
    "aliyuneventbusname":"Housekeeping-Bus",
    "id":"d100262d-90c7-4caf-a3b5-813f3526a1f7-****",
    "source":"housekeeping.scheduledevent",
    "time":"2022-09-21T05:00:00Z",
    "aliyunregionid":"cn-beijing",
    "type":"eventbridge:Events:ScheduledEvent"
}

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
TimeZone	String	GMT+8:00	The time zone.
Schedule	String	0 /10 * * *	The cron expression that is used when you select Fixed Period for Trigger Period.
UserData	Object	{"key":"value"}	The custom parameters in the format of a JSON object.

HTTP workflow scheduling

{
    "datacontenttype": "application/json",
    "aliyunaccountid": "164901546557****",
    "data": {
        "headers": {
            "content-length": "0",
            "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7",
            "Host": "164901546557****.eventbridge.cn-hangzhou.aliyuncs.com",
            "Accept-Encoding": "gzip, deflate",
            "X-Forwarded-Port": "80",
            "Upgrade-Insecure-Requests": "1",
            "X-Forwarded-For": "183.247.0.***",
            "Accept-Language": "zh-CN,zh;q=0.9",
            "X-Real-IP": "183.247.0.***",
            "X-Scheme": "http"
        },
        "path": "/webhook/putEvents",
        "body": "",
        "httpMethod": "GET",
        "queryString": {}
    },
    "subject": "acs:eventbridge:cn-hangzhou:164901546557****:eventbus/eventbus-created-by-fnf-466ccc7e-418a-403f-8d96-2d73a8e****/eventsource/httpschedule",
    "aliyunoriginalaccountid": "164901546557****",
    "source": "httpschedule",
    "type": "eventbridge:Events:HTTPEvent",
    "aliyunpublishtime": "2023-08-06T18:37:01.666Z",
    "specversion": "1.0",
    "aliyuneventbusname": "eventbus-created-by-fnf-466ccc7e-418a-403f-8d96-2d73a8e****",
    "id": "6751261d-e496-4b36-a707-3c087bf3****",
    "time": "2023-08-07T02:37:01.666+08:00",
    "aliyunregionid": "cn-hangzhou",
    "aliyunpublishaddr": "183.247.0.***"
}

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
headers	Object	{ "Accept": "application/json" }	The HTTP request header.
path	String	/webhook/putEvents	The path of the request.
body	Object	{ "filePath": "/tmp/uploader" }	The HTTP request body.
httpMethod	String	GET	The HTTP invocation method.
queryString	String	username=leo	The `query` content in the HTTP URL excludes the token that is used to request the webhook.

Event scheduling of cloud services

{
    "id":"c2g71017-6f65-fhcf-a814-a396fc8d****",
    "source":"OSS-FunctionFlow-osstrigger",
    "specversion":"1.0",
    "type":"oss:PutObject",
    "datacontenttype":"application/json; charset=utf-8",
    "subject":"acs:mns:cn-hangzhou:164901546557****:queues/zeus",
    "time":"2021-04-08T06:28:17.093Z",
    "aliyunaccountid":"1649015465574023",
    "aliyunpublishtime":"2021-10-15T07:06:34.028Z",
    "aliyunoriginalaccountid":"164901546557****",
    "aliyuneventbusname":"OSS-FunctionFlow-osstrigger",
    "aliyunregionid":"cn-chengdu",
    "aliyunpublishaddr":"42.120.XX.XX",
    "data":{
      *** This content varies based on the event source. ***
    }
}

The parameters contained in the data section vary based on the type of event source of the Alibaba Cloud service. For more information about the types and formats of cloud service event sources, see Alibaba Cloud service event sources.

Simple Log Service workflow scheduling

[
	{
    "datacontenttype": "application/json;charset=utf-8",
    "aliyunaccountid": "164901546557****",
    "data": {
        "key1": "value1",
        "key2": "value2",
        "__topic__": "test_topic",
        "__source__": "test_source",
        "__client_ip__": "122.231.XX.XX",
        "__receive_time__": "1663487595",
        "__pack_id__": "59b662b2257796****"
    },
    "subject": "acs:log:cn-qingdao:164901546557****:project/qiingdaoproject/logstore/qingdao-logstore-1",
    "aliyunoriginalaccountid": "164901546557****",
    "source": "SLS-FunctionFlow-slstrigger",
    "type": "sls:connector",
    "aliyunpublishtime": "2022-09-18T07:53:15.387Z",
    "specversion": "1.0",
    "aliyuneventbusname": "SLS-FunctionFlow-slstrigger",
    "id": "qiingdaoproject-qingdao-logstore-1-1-MTY2MzExODM5ODY4NjAxOTQyMw****",
    "time": "2022-09-18T07:53:12Z",
    "aliyunregionid": "cn-qingdao",
    "aliyunpublishaddr": "10.50.XX.XX"
  }
]

The following table describes the parameters contained in data. The fields that start and end with __ are the system fields of Simple Log Service. For more information, see Reserved fields. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
key1	String	testKey	The field in the log of the user.
__topic__	String	testTopic	The log topic.
__source__	String	testSource	The device from which the log is collected.
__client_ip__	String	122.231.XX.XX	The IP address of the host in which the log resides.
__receive_time__	String	1663487595	The time when the log arrived at the server.
__pack_id__	String	59b662b2257796****	The unique ID of the log group to which the log belongs.

MNS workflow scheduling

[
  {
    "id":"c2g71017-6f65-fhcf-a814-a396fc8d****",
    "source":"MNS-FunctionFlow-mnstrigger",
    "specversion":"1.0",
    "type":"mns:Queue:SendMessage",
    "datacontenttype":"application/json; charset=utf-8",
    "subject":"acs:mns:cn-hangzhou:164901546557****:queues/zeus",
    "time":"2023-04-08T06:28:17.093Z",
    "aliyunaccountid":"1649015465574023",
    "aliyunpublishtime":"2023-10-15T07:06:34.028Z",
    "aliyunoriginalaccountid":"164901546557****",
    "aliyuneventbusname":"MNS-Function-mnstrigger",
    "aliyunregionid":"cn-chengdu",
    "aliyunpublishaddr":"42.120.XX.XX",
    "data":{
        "requestId":"606EA3074344430D4C81****",
        "messageId":"C6DB60D1574661357FA227277445****",
        "messageBody":"TEST"
    }
  }
]

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
requestId	String	606EA3074344430D4C81****	The request ID. The ID of each request is unique.
messageId	String	C6DB60D1574661357FA227277445****	The message ID. The ID of each message is unique.
messageBody	String	TEST	The message body.

RocketMQ workflow scheduling

[
	{
    "id":"94ebc15f-f0db-4bbe-acce-56fb72fb****",
    "source":"RocketMQ-rocketmq-schedule",
    "specversion":"1.0",
    "type":"mq:Topic:SendMessage",
    "datacontenttype":"application/json; charset=utf-8",
    "subject":"acs:mq:cn-hangzhou:164901546557****:MQ_INST_164901546557****_BXhFHryi%TopicName",
    "time":"2023-04-08T06:01:20.766Z",
    "aliyunaccountid":"164901546557****",
    "aliyunpublishtime":"2023-10-15T02:05:16.791Z",
    "aliyunoriginalaccountid":"164901546557****",
    "aliyuneventbusname":"RocketMQ-Function-rocketmq-trigger",
    "aliyunregionid":"cn-chengdu",
    "aliyunpublishaddr":"42.120.XX.XX",
    "data":{
        "topic":"TopicName",
        "systemProperties":{
            "MIN_OFFSET":"0",
            "TRACE_ON":"true",
            "MAX_OFFSET":"8",
            "MSG_REGION":"cn-hangzhou",
            "KEYS":"systemProperties.KEYS",
            "CONSUME_START_TIME":1628577790396,
            "TAGS":"systemProperties.TAGS",
            "INSTANCE_ID":"MQ_INST_164901546557****_BXhFHryi"
        },
        "userProperties":{

        },
        "body":"TEST"
    }
  }
]

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
topic	String	TopicName	The topic name.
systemProperties	Map		The system properties.
MIN_OFFSET	Int	0	The earliest offset.
TRACE_ON	Boolean	true	Specifies whether to include a message trace in the system properties. Valid values: true false
MAX_OFFSET	Int	8	The latest offset.
MSG_REGION	String	cn-hangzhou	The region from which the message was sent.
KEYS	String	systemProperties.KEYS	The keys that are used to filter the message.
CONSUME_START_TIME	Long	1628577790396	The start time of message consumption. This value is a UNIX timestamp representing the number of milliseconds that have elapsed since January 1, 1970, 00:00:00 UTC.
UNIQ_KEY	String	AC14C305069E1B28CDFA3181CDA2****	The unique key of the message.
TAGS	String	systemProperties.TAGS	The tags that are used to filter the message.
INSTANCE_ID	String	MQ_INST_123456789098****_BXhFHryi	The ID of the ApsaraMQ for RocketMQ instance.
userProperties	Map	None	The user properties.
body	String	TEST	The message body.

RabbitMQ workflow scheduling

[
	{
    "id":"bj694332-4cj1-389e-9d8c-b137h30b****",
    "source":"RabbitMQ-Function-rabbitmq-trigger",
    "specversion":"1.0",
    "type":"amqp:Queue:SendMessage",
    "datacontenttype":"application/json;charset=utf-8",
    "subject":"acs:amqp:cn-hangzhou:164901546557****:/instances/amqp-cn-tl32e756****/vhosts/eb-connect/queues/housekeeping",
    "time":"2023-08-12T06:56:40.709Z",
    "aliyunaccountid":"164901546557****",
    "aliyunpublishtime":"2023-10-15T08:58:55.140Z",
    "aliyunoriginalaccountid":"164901546557****",
    "aliyuneventbusname":"RabbitMQ-Function-rabbitmq-trigger",
    "aliyunregionid":"cn-chengdu",
    "aliyunpublishaddr":"42.120.XX.XX",
    "data":{
        "envelope":{
            "deliveryTag":98,
            "exchange":"",
            "redeliver":false,
            "routingKey":"housekeeping"
        },
        "body":{
            "Hello":"RabbitMQ"
        },
        "props":{
            "contentEncoding":"UTF-8",
            "messageId":"f7622d51-e198-41de-a072-77c1ead7****"
        }
    }
  }
]

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
body	Map		The message body.
Hello	String	EventBridge	The user data.
props	Map		The properties of the message.
contentEncoding	String	utf-8	The format in which the message body is encoded.
messageId	String	f7622d51-e198-41de-a072-77c1ead7****	The message ID. The ID of each message is unique.
envelope	Map		The information about the message envelope.
deliveryTag	Int	98	The message tag.
exchange	String	None	The name of the exchange that sends the message.
redeliver	Boolean	false	Specifies whether the message can be resent. Valid values: true false
routingKey	String	housekeeping	The rule that is used to route the message.

Kafka workflow scheduling

[
	{
    "specversion":"1.0",
    "id":"8e215af8-ca18-4249-8645-f96c1026****",
    "source":"acs:alikafka",
    "type":"alikafka:Topic:Message",
    "subject":"acs:alikafka_pre-cn-i7m2t7t1****:topic:mytopic",
    "datacontenttype":"application/json; charset=utf-8",
    "time":"2023-06-23T02:49:51.589Z",
    "aliyunaccountid":"164901546557****",
    "data":{
        "topic":"****",
        "partition":7,
        "offset":25,
        "timestamp":1655952591589,
        "headers":{
            "headers":[

            ],
            "isReadOnly":false
        },
        "key":"keytest",
        "value":"hello kafka msg"
    }
}
]

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
topic	String	TopicName	The topic name.
partition	Int	1	The information about partitions on the ApsaraMQ for Kafka instance.
offset	Int	0	The message offset of the ApsaraMQ for Kafka instance.
timestamp	String	1655952591589	The timestamp that indicates when message consumption started.

Data Transmission Service (DTS) workflow scheduling

{
  "data": {
    "id": 321****,
    "topicPartition": {
      "hash": 0,
      "partition": 0,
      "topic": "cn_hangzhou_rm_1234****_test_version2"
    },
    "offset": 3218099,
    "sourceTimestamp": 1654847757,
    "operationType": "UPDATE",
    "schema": {
      "recordFields": [
        {
          "fieldName": "id",
          "rawDataTypeNum": 8,
          "isPrimaryKey": true,
          "isUniqueKey": false,
          "fieldPosition": 0
        },
        {
          "fieldName": "topic",
          "rawDataTypeNum": 253,
          "isPrimaryKey": false,
          "isUniqueKey": false,
          "fieldPosition": 1
        }
      ],
      "nameIndex": {
        "id": {
          "fieldName": "id",
          "rawDataTypeNum": 8,
          "isPrimaryKey": true,
          "isUniqueKey": false,
          "fieldPosition": 0
        },
        "topic": {
          "fieldName": "topic",
          "rawDataTypeNum": 253,
          "isPrimaryKey": false,
          "isUniqueKey": false,
          "fieldPosition": 1
        }
      },
      "schemaId": "(hangzhou-test-db,hangzhou-test-db,message_info)",
      "databaseName": "hangzhou--test-db",
      "tableName": "message_info",
      "primaryIndexInfo": {
        "indexType": "PrimaryKey",
        "indexFields": [
          {
            "fieldName": "id",
            "rawDataTypeNum": 8,
            "isPrimaryKey": true,
            "isUniqueKey": false,
            "fieldPosition": 0
          }
        ],
        "cardinality": 0,
        "nullable": true,
        "isFirstUniqueIndex": false
      },
      "uniqueIndexInfo": [],
      "foreignIndexInfo": [],
      "normalIndexInfo": [],
      "databaseInfo": {
        "databaseType": "MySQL",
        "version": "5.7.35-log"
      },
      "totalRows": 0
    },
    "beforeImage": {
      "recordSchema": {
        "recordFields": [
          {
            "fieldName": "id",
            "rawDataTypeNum": 8,
            "isPrimaryKey": true,
            "isUniqueKey": false,
            "fieldPosition": 0
          },
          {
            "fieldName": "topic",
            "rawDataTypeNum": 253,
            "isPrimaryKey": false,
            "isUniqueKey": false,
            "fieldPosition": 1
          }
        ],
        "nameIndex": {
          "id": {
            "fieldName": "id",
            "rawDataTypeNum": 8,
            "isPrimaryKey": true,
            "isUniqueKey": false,
            "fieldPosition": 0
          },
          "topic": {
            "fieldName": "topic",
            "rawDataTypeNum": 253,
            "isPrimaryKey": false,
            "isUniqueKey": false,
            "fieldPosition": 1
          }
        },
        "schemaId": "(hangzhou-test-db,hangzhou-test-db,message_info)",
        "databaseName": "hangzhou-test-db",
        "tableName": "message_info",
        "primaryIndexInfo": {
          "indexType": "PrimaryKey",
          "indexFields": [
            {
              "fieldName": "id",
              "rawDataTypeNum": 8,
              "isPrimaryKey": true,
              "isUniqueKey": false,
              "fieldPosition": 0
            }
          ],
          "cardinality": 0,
          "nullable": true,
          "isFirstUniqueIndex": false
        },
        "uniqueIndexInfo": [],
        "foreignIndexInfo": [],
        "normalIndexInfo": [],
        "databaseInfo": {
          "databaseType": "MySQL",
          "version": "5.7.35-log"
        },
        "totalRows": 0
      },
      "values": [
        {
          "data": 115
        },
        {
          "data": {
            "hb": [
              104,
              101,
              108,
              108,
              111
            ],
            "offset": 0,
            "isReadOnly": false,
            "bigEndian": true,
            "nativeByteOrder": false,
            "mark": -1,
            "position": 0,
            "limit": 9,
            "capacity": 9,
            "address": 0
          },
          "charset": "utf8mb4"
        }
      ],
      "size": 45
    },
    "afterImage": {
      "recordSchema": {
        "recordFields": [
          {
            "fieldName": "id",
            "rawDataTypeNum": 8,
            "isPrimaryKey": true,
            "isUniqueKey": false,
            "fieldPosition": 0
          },
          {
            "fieldName": "topic",
            "rawDataTypeNum": 253,
            "isPrimaryKey": false,
            "isUniqueKey": false,
            "fieldPosition": 1
          }
        ],
        "nameIndex": {
          "id": {
            "fieldName": "id",
            "rawDataTypeNum": 8,
            "isPrimaryKey": true,
            "isUniqueKey": false,
            "fieldPosition": 0
          },
          "topic": {
            "fieldName": "topic",
            "rawDataTypeNum": 253,
            "isPrimaryKey": false,
            "isUniqueKey": false,
            "fieldPosition": 1
          }
        },
        "schemaId": "(hangzhou-test-db,hangzhou-test-db,message_info)",
        "databaseName": "hangzhou-test-db",
        "tableName": "message_info",
        "primaryIndexInfo": {
          "indexType": "PrimaryKey",
          "indexFields": [
            {
              "fieldName": "id",
              "rawDataTypeNum": 8,
              "isPrimaryKey": true,
              "isUniqueKey": false,
              "fieldPosition": 0
            }
          ],
          "cardinality": 0,
          "nullable": true,
          "isFirstUniqueIndex": false
        },
        "uniqueIndexInfo": [],
        "foreignIndexInfo": [],
        "normalIndexInfo": [],
        "databaseInfo": {
          "databaseType": "MySQL",
          "version": "5.7.35-log"
        },
        "totalRows": 0
      },
      "values": [
        {
          "data": 115
        },
        {
          "data": {
            "hb": [
              98,
              121,
              101
            ],
            "offset": 0,
            "isReadOnly": false,
            "bigEndian": true,
            "nativeByteOrder": false,
            "mark": -1,
            "position": 0,
            "limit": 11,
            "capacity": 11,
            "address": 0
          },
          "charset": "utf8mb4"
        }
      ],
      "size": 47
    }
  },
  "id": "12f701a43741d404fa9a7be89d9acae0-321****",
  "source": "DTSstreamDemo",
  "specversion": "1.0",
  "type": "dts:ConsumeMessage",
  "datacontenttype": "application/json; charset=utf-8",
  "time": "2022-06-10T07:55:57Z",
  "subject": "acs:dts:cn-hangzhou:12345****:kk123abc60g782/dtsabcdet1ro"
}

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter			Type	Example	Description
id			String	321****	The ID of the DTS data entry.
topicPartition			Array		The partition information about the topic to which the event is pushed.
	hash		String	0	The underlying storage parameter of DTS.
	partition		String	0	The partition.
	topic		String	cn_hangzhou_rm_1234****_test_version2	The topic name.
offset			Int	3218099	The offset of the DTS data entry.
sourceTimestamp			Int	1654847757	The timestamp that indicates when the DTS data entry was generated.
operationType			String	UPDATE	The type of the operation on the DTS data entry.
schema			Array		The schema information about the database.
	recordFields		Array		The details of fields.
		fieldName	String	id	The name of the field.
		rawDataTypeNum	Int	8	The mapped value of the field type.
		isPrimaryKey	Boolean	true	Specifies whether the field is a primary key field.
		isUniqueKey	Boolean	false	Specifies whether the field has a unique key.
		fieldPosition	String	0	The position of the field.
	nameIndex		Array		The indexing information about the fields based on field names.
	schemaId		String	(hangzhou-test-db,hangzhou-test-db,message_info)	The ID of the database schema.
	databaseName		String	hangzhou--test-db	The database name.
	tableName		String	message_info	The table name.
	primaryIndexInfo		Array		The primary key indexes.
		indexType	String	PrimaryKey	The index type.
		indexFields	Array		The fields on which the indexes are created.
		cardinality	String	0	The cardinality of the primary keys.
		nullable	Boolean	true	Specifies whether the primary keys can be null.
		isFirstUniqueIndex	Boolean	false	Specifies whether the index is the first unique index.
	uniqueIndexInfo		String	[]	The unique indexes.
	foreignIndexInfo		String	[]	The indexes for foreign keys.
	normalIndexInfo		String	[]	The regular indexes.
	databaseInfo		Array		The information about the database.
		databaseType	String	MySQL	The type of the database engine.
		version	String	5.7.35-log	The version of the database engine.
	totalRows		Int	0	The total number of rows in the table.
beforeImage			String		The image that records field values before the operation is performed.
	values		String		The field values recorded.
	size		Int	47	The size of the fields recorded.
afterImage			String		The image that records field values after the operation is performed.

MQTT workflow scheduling

[
	{
    "specversion":"1.0",
    "id":"AC1EC0C950650816F27D46F7D7CA****",
    "source":"acs:mqtt",
    "type":"mqtt:Topic:SendMessage",
    "subject":"acs:mq:cn-hangzhou:143998900779****:topic/mqtt-cn-2r42qam****/housekee****",
    "datacontenttype":"application/json; charset\u003dutf-8",
    "time":"2022-06-22T03:53:47.959Z",
    "aliyunaccountid":"143998900779****",
    "data":{
        "props":{
            "firstTopic":"housekee****",
            "secondTopic":"/testMq4****",
            "clientId":"GID_****"
        },
        "body":"TEST"
    }
  }
]

The following table describes the parameters contained in data. For information about parameters that are defined in the CloudEvents specification, see Overview.

Parameter	Type	Example	Description
props	Map		The properties of the message.
firstTopic	String	housekee****	The parent topic that is used to send and receive messages.
secondTopic	String	/testMq4****	The child topic.
clientId	String	GID_****	The client ID.
body	String	TEST	The message body.