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Vitess Replace Field Value

The ReplaceFieldValue SMT replaces the value of a specified field from the event record. When the connector is configured to provide transaction metadata, use this SMT to redact the transaction.id field to avoid storing a duplicate entry of the VGTID, or use for both transaction.id and source.vgtid to avoid storing any large VGTIDs. This transformation is designed for use only with the Debezium connector for Vitess.

The SMT uses the field_names configuration option to specify a comma-separated list of paths that identify the fields that will have their values replaced. The SMT uses the field_value configuration option to specify the replacement value for the fields. Defaults to the empty string.

The SMT replaces the value of each field that you specify. The following example shows how to add the SMT to the connector configuration so that it replaces the values of specific fields from the change event records that the connector emits.

Example: Configuring the ReplaceFieldValue SMT

"connector.class": "io.debezium.connector.vitess.VitessConnector",
...
"transforms": "replaceFieldValue",
"transforms.replaceFieldValue.type": "io.debezium.connector.vitess.transforms.ReplaceFieldValue",
"transforms.replaceFieldValue.field_names": "transaction.id",
...

The following example shows the value of a change event record before and after the transformation is applied.

Example 1. Effect of applying the ReplaceFieldValue SMT
Value before the SMT processes the record
{
    "before": {...}
    "after": {...}
    "source": {...}
    "transaction": {
        "id": "[{\"keyspace\":\"test_unsharded_keyspace\",\"shard\":\"0\",\"gtid\":\"MySQL56/e03ece6c-4c04-11ec-8e20-0242ac110004:1-68\"}]",
        "total_order": 1,
        "data_collection_order": 1
      }
}
Value after the SMT processes the record
{
    "before": {...}
    "after": {...}
    "source": {...}
    "transaction": {
        "id": "",
        "total_order": 1,
        "data_collection_order": 1
      }
}

Configuration options for the ReplaceFieldValue SMT

The following table lists the configuration options that you can use with the ReplaceFieldValue SMT.

Table 1. ReplaceFieldValue SMT configuration options

Property

Description

Type

Default

Valid Values

Importance

fields_names

A comma-separated list that specifies the paths of the fields to replace values for the event record, for example, transaction.id).

List

No default value

Non-empty list

High

field_value

The value that each replace field is set to, for example.

List

"" (Empty string)

String value

Medium