Remove_by_pattern processor
The remove_by_pattern
processor removes the root-level fields from a document by using specified wildcard patterns.
Syntax
The following is the syntax for the remove_by_pattern
processor:
{
"remove_by_pattern": {
"field_pattern": "field_name_prefix*"
}
}
Configuration parameters
The following table lists the required and optional parameters for the remove_by_pattern
processor.
Parameter | Required/Optional | Description |
---|---|---|
field_pattern | Optional | Removes fields that match the specified pattern. All of the metadata fields, such as _index , _version , _version_type , and _id , are ignored if they match the pattern. This option only supports the root-level fields in the document. |
exclude_field_pattern | Optional | Removes fields that do not match the specified pattern. All of the metadata fields, such as _index , _version , _version_type , and _id , are ignored if they do not match the pattern. This option only supports the root-level fields in the document. The field_pattern and exclude_field_pattern options are mutually exclusive. |
description | Optional | A brief description of the processor. |
if | Optional | A condition for running the processor. |
ignore_failure | Optional | Specifies whether the processor continues execution even if it encounters errors. If set to true , the failure is ignored. Default is false . |
on_failure | Optional | A list of processors to run if the processor fails. |
tag | Optional | An identifier tag for the processor. Useful for debugging in order to distinguish between processors of the same type. |
Using the processor
Follow these steps to use the processor in a pipeline.
Step 1: Create a pipeline
The following query creates a pipeline named remove_fields_by_pattern
that removes the fields that match the pattern foo*
:
PUT /_ingest/pipeline/remove_fields_by_pattern
{
"description": "Pipeline that removes the fields by patterns.",
"processors": [
{
"remove_by_pattern": {
"field_pattern": "foo*"
}
}
]
}
Step 2 (Optional): Test the pipeline
It is recommended that you test your pipeline before you ingest documents.
To test the pipeline, run the following query:
POST _ingest/pipeline/remove_fields_by_pattern/_simulate
{
"docs": [
{
"_index": "testindex1",
"_id": "1",
"_source":{
"foo1": "foo1",
"foo2": "foo2",
"bar": "bar"
}
}
]
}
Response
The following example response confirms that the pipeline is working as expected:
{
"docs": [
{
"doc": {
"_index": "testindex1",
"_id": "1",
"_source": {
"bar": "bar"
},
"_ingest": {
"timestamp": "2023-08-24T18:02:13.218986756Z"
}
}
}
]
}
Step 3: Ingest a document
The following query ingests a document into an index named testindex1
:
PUT testindex1/_doc/1?pipeline=remove_fields_by_pattern
{
"foo1": "foo1",
"foo2": "foo2",
"bar": "bar"
}
Step 4 (Optional): Retrieve the document
To retrieve the document, run the following query:
GET testindex1/_doc/1