Document Database Service DDS¶

Using DDS triggers, each time a table in the database is updated, a Functiongraph function can be triggered to perform additional work. For more information about how to use DDS triggers, see Using a DDS Trigger.

DDS example event¶

{
  "records": [
    {
      "event_source": "dds",
      "event_name": "insert",
      "region": "{region}",
      "event_version": "1.0",
      "dds": {
        "size_bytes": "100",
        "token": "{\"_data\": \"825D8C2F4D0000001529295A100474039A3412A64BA89041DC952357FB4446645F696400645D8C2F8E5BECCB6CF5370D6A0004\"}",
        "full_document": "{\"_id\": {\"$oid\": \"5d8c2f8e5beccb6cf5370d6a\"},\"name\": \"dds\",\"age\": {\"$numberDouble \": \"52.0\"}}",
        "ns": "{\"db\": \"functiongraph\",\"coll\": \"person\"}"
      },
      "event_source_id": "e6065860-f7b8-4cca-80bd-24ef2a3bb748"
    }
  ]
}

Parameter description¶

Parameter	Type	Example Value	Description
region	String	{region}	The region where the DDS instance is located
event_version	String	1.0	Event protocol version
event_source	String	dds	Source of the event
event_name	String	insert	Event name
size_bytes	Int	100	The number of bytes in the message
token	String	Reference examples	Base64 encoded data
full_document	String	Reference examples	Complete file information
ns	String	Reference examples	Column Name
event_source_id	String	e6065860-f7b8-4cca-80bd-24ef2a3bb748	Event source unique identifier

Example¶

handler.go¶

package main

import (
	"encoding/json"
	"fmt"

	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/events/dds"
	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/go-api/context"
	"github.com/opentelekomcloud-community/otc-functiongraph-go-runtime/go-runtime/pkg/runtime"
)

// Example for Document Database Service handler
func DdsTest(payload []byte, ctx context.RuntimeContext) (interface{}, error) {
	var ddsEvent dds.DDSTriggerEvent
	err := json.Unmarshal(payload, &ddsEvent)
	if err != nil {
		fmt.Println("Unmarshal failed")
		return "invalid data", err
	}
	ctx.GetLogger().Logf("payload:%s", ddsEvent.String())
	return "ok", nil
}

func main() {
	runtime.Register(DdsTest)
}

last updated: 2025-10-24 14:39:45 UTC - commit: 373fe56a6b249d6515a713ff6d87064ece946718