HTML strip processor
The html_strip processor removes HTML tags from string fields in incoming documents. This processor is useful when indexing data from webpages or other sources that may contain HTML markup. HTML tags are replaced with newline characters (\n).
The following is the syntax for the html_strip processor:
{
"html_strip": {
"field": "webpage"
}
}
Configuration parameters
The following table lists the required and optional parameters for the html_strip processor.
| Parameter | Required/Optional | Description |
|---|---|---|
field | Required | The string field from which to remove HTML tags. |
target_field | Optional | The field that receives the plain text version after stripping HTML tags. If not specified, then the field is updated in-place. |
ignore_missing | Optional | Specifies whether the processor should ignore documents that do not contain the specified field. Default is false. |
description | Optional | A description of the processor’s purpose or configuration. |
if | Optional | Specifies to conditionally execute the processor. |
ignore_failure | Optional | Specifies to ignore processor failures. See Handling pipeline failures. |
on_failure | Optional | Specifies a list of processors to run if the processor fails during execution. These processors are executed in the order they are specified. See Handling pipeline failures. |
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 strip-html-pipeline that uses the html_strip processor to remove HTML tags from the description field and store the processed value in a new field named cleaned_description:
PUT _ingest/pipeline/strip-html-pipeline
{
"description": "A pipeline to strip HTML from description field",
"processors": [
{
"html_strip": {
"field": "description",
"target_field": "cleaned_description"
}
}
]
}
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/strip-html-pipeline/_simulate
{
"docs": [
{
"_source": {
"description": "This is a <b>test</b> description with <i>some</i> HTML tags."
}
}
]
}
Response
The following example response confirms that the pipeline is working as expected:
{
"docs": [
{
"doc": {
"_index": "_index",
"_id": "_id",
"_source": {
"description": "This is a <b>test</b> description with <i>some</i> HTML tags.",
"cleaned_description": "This is a test description with some HTML tags."
},
"_ingest": {
"timestamp": "2024-05-22T21:46:11.227974965Z"
}
}
}
]
}
Step 3: Ingest a document
The following query ingests a document into an index named products:
PUT products/_doc/1?pipeline=strip-html-pipeline
{
"name": "Product 1",
"description": "This is a <b>test</b> product with <i>some</i> HTML tags."
}
Response
The response shows that the request has indexed the document into the index products and will index all documents with the description field containing HTML tags while storing the plain text version in the cleaned_description field:
{
"_index": "products",
"_id": "1",
"_version": 1,
"result": "created",
"_shards": {
"total": 2,
"successful": 1,
"failed": 0
},
"_seq_no": 0,
"_primary_term": 1
}
Step 4 (Optional): Retrieve the document
To retrieve the document, run the following query:
GET products/_doc/1
Response
The response includes both the original description field and the cleaned_description field with HTML tags removed:
{
"_index": "products",
"_id": "1",
"_version": 1,
"_seq_no": 0,
"_primary_term": 1,
"found": true,
"_source": {
"cleaned_description": "This is a test product with some HTML tags.",
"name": "Product 1",
"description": "This is a <b>test</b> product with <i>some</i> HTML tags."
}
}