HTML strip character filter

Strips HTML elements from a text and replaces HTML entities with their decoded value (e.g, replaces & with &).

The html_strip filter uses Lucene’s HTMLStripCharFilter.

Example

The following analyze API request uses the html_strip filter to change the text I'm so happy! to \nI'm so happy!\n.

  GET /_analyze { "tokenizer": "keyword", "char_filter": [ "html_strip" ], "text": "<p>I&apos;m so <b>happy</b>!</p>" }  

The filter produces the following text:

 [ \nI'm so happy!\n ]

Add to an analyzer

The following create index API request uses the html_strip filter to configure a new custom analyzer.

  PUT /my-index-000001 { "settings": { "analysis": { "analyzer": { "my_analyzer": { "tokenizer": "keyword", "char_filter": [ "html_strip" ] } } } } }  

Configurable parameters

escaped_tags: (Optional, array of strings) Array of HTML elements without enclosing angle brackets (< >). The filter skips these HTML elements when stripping HTML from the text. For example, a value of [ "p" ] skips the  HTML element.

Customize

To customize the html_strip filter, duplicate it to create the basis for a new custom character filter. You can modify the filter using its configurable parameters.

The following create index API request configures a new custom analyzer using a custom html_strip filter, my_custom_html_strip_char_filter.

The my_custom_html_strip_char_filter filter skips the removal of the  HTML element.

  PUT my-index-000001 { "settings": { "analysis": { "analyzer": { "my_analyzer": { "tokenizer": "keyword", "char_filter": [ "my_custom_html_strip_char_filter" ] } }, "char_filter": { "my_custom_html_strip_char_filter": { "type": "html_strip", "escaped_tags": [ "b" ] } } } } }  