substitute_string
The substitute_string processor matches a key’s value against a regular expression and replaces all matches with a replacement string. substitute_string is a mutate string processor.
Configuration
The following table describes the options you can use to configure the substitute_string processor.
| Option | Required | Type | Description | 
|---|---|---|---|
| entries | Yes | List | List of entries. Valid values are source,from, andto. | 
| source | N/A | N/A | The key to modify. | 
| from | N/A | N/A | The Regex String to be replaced. Special regex characters such as [and]must be escaped using\\when using double quotes and\ when using single quotes. See Java Patterns for more information. | 
| to | N/A | N/A | The String to be substituted for each match of from. |