[[analysis-htmlstrip-charfilter]]
=== HTML Strip Char Filter

The `html_strip` character filter strips HTML elements from the text and
replaces HTML entities with their decoded value (e.g. replacing `&amp;` with
`&`).

[float]
=== Example output

[source,js]
---------------------------
POST _analyze
{
  "tokenizer":      "keyword", <1>
  "char_filter":  [ "html_strip" ],
  "text": "<p>I&apos;m so <b>happy</b>!</p>"
}
---------------------------
// CONSOLE
<1> The <<analysis-keyword-tokenizer,`keyword` tokenizer>> returns a single term.

/////////////////////

[source,js]
----------------------------
{
  "tokens": [
    {
      "token": "\nI'm so happy!\n",
      "start_offset": 0,
      "end_offset": 32,
      "type": "word",
      "position": 0
    }
  ]
}
----------------------------
// TESTRESPONSE

/////////////////////


The above example returns the term:

[source,text]
---------------------------
[ \nI'm so happy!\n ]
---------------------------

The same example with the `standard` tokenizer would return the following terms:

[source,text]
---------------------------
[ I'm, so, happy ]
---------------------------

[float]
=== Configuration

The `html_strip` character filter accepts the following parameter:

[horizontal]
`escaped_tags`::

    An array of HTML tags which should not be stripped from the original text.

[float]
=== Example configuration

In this example, we configure the `html_strip` character filter to leave `<b>`
tags in place:

[source,js]
----------------------------
PUT my_index
{
  "settings": {
    "analysis": {
      "analyzer": {
        "my_analyzer": {
          "tokenizer": "keyword",
          "char_filter": ["my_char_filter"]
        }
      },
      "char_filter": {
        "my_char_filter": {
          "type": "html_strip",
          "escaped_tags": ["b"]
        }
      }
    }
  }
}

POST my_index/_analyze
{
  "analyzer": "my_analyzer",
  "text": "<p>I&apos;m so <b>happy</b>!</p>"
}
----------------------------
// CONSOLE

/////////////////////

[source,js]
----------------------------
{
  "tokens": [
    {
      "token": "\nI'm so <b>happy</b>!\n",
      "start_offset": 0,
      "end_offset": 32,
      "type": "word",
      "position": 0
    }
  ]
}
----------------------------
// TESTRESPONSE

/////////////////////


The above example produces the following term:

[source,text]
---------------------------
[ \nI'm so <b>happy</b>!\n ]
---------------------------
