[Enhancement] Add String field parsing transforms

[yoniwg]

Add a transform that parse a string field into other primitive values or into array, such as:
int, long, float, double, boolean (or an array of one of these).

Configuration

• transforms.<name>.type - One of:
  • com.github.jcustenborder.kafka.connect.transform.common.ParseString$Key
  • com.github.jcustenborder.kafka.connect.transform.common.ParseString$Value
• transforms.<name>.fields - field1,field2,...
• transforms.<name>.type - One of: int, long, float, double, boolean
• transforms.<name>.isArray - true or false (Default to false)

Examples

Example 1

If the source contains

"field1": "1" - Parse Integer

Then after applying the following transformation:

"transforms":"parseInt",
"transforms.parseInt.type":"com.github.jcustenborder.kafka.connect.transform.common.ParseString$Value",
"transforms.parseInt.fields":"field1",
"transforms.parseInt.type":"int",

The result will be:

"field1": 1

Example 2 - Array

If the source contains

"field1": "1,2,3"

Then after applying the following transformation:

"transforms":"parseIntArray",
"transforms.parseIntArray.type":"com.github.jcustenborder.kafka.connect.transform.common.ParseString$Value",
"transforms.parseIntArray.fields":"field1",
"transforms.parseIntArray.type":"int",
"transforms.parseIntArray.isArray":"true",

The result will be:

"field1": [1,2,3]

Example 3 - Multiple Fields

If the source contains

"field1": "true",
"field2": "false"

Then after applying the following transformation:

"transforms":"parseMultipleBooleans",
"transforms.parseMultipleBooleans.type":"com.github.jcustenborder.kafka.connect.transform.common.ParseString$Value",
"transforms.parseMultipleBooleans.fields":"field1,field2",
"transforms.parseMultipleBooleans.type":"boolean",

The result will be:

"field1": true,
"field2": false

Example 4 - Supporting Avro null values

If the source contains

"field1": {"string": "true"},
"field2": null

Then after applying the following transformation:

"transforms":"parseMultipleOptionalBooleans",
"transforms.parseMultipleOptionalBooleans.type":"com.github.jcustenborder.kafka.connect.transform.common.ParseString$Value",
"transforms.parseMultipleOptionalBooleans.fields":"field1,field2",
"transforms.parseMultipleOptionalBooleans.type":"boolean",

The result will be:

"field1": {"boolean": true},
"field2": null

[yoniwg]

If you think it is useful - Let me know and I may implement this transform