Multiplexer token filter
The multiplexer
token filter allows you to create multiple versions of the same token by applying different filters. This is useful when you want to analyze the same token in multiple ways. For example, you may want to analyze a token using different stemming, synonyms, or n-gram filters and use all of the generated tokens together. This token filter works by duplicating the token stream and applying different filters to each copy.
The multiplexer
token filter removes duplicate tokens from the token stream.
The multiplexer
token filter does not support multiword synonym
or synonym_graph
token filters or shingle
token filters because they need to analyze not only the current token but also upcoming tokens in order to determine how to transform the input correctly.
Parameters
The multiplexer
token filter can be configured with the following parameters.
Parameter | Required/Optional | Data type | Description |
---|---|---|---|
filters | Optional | List of strings | A comma-separated list of token filters to apply to each copy of the token stream. Default is an empty list. |
preserve_original | Optional | Boolean | Whether to keep the original token as one of the outputs. Default is true . |
Example
The following example request creates a new index named multiplexer_index
and configures an analyzer with a multiplexer
filter:
PUT /multiplexer_index
{
"settings": {
"analysis": {
"filter": {
"english_stemmer": {
"type": "stemmer",
"name": "english"
},
"synonym_filter": {
"type": "synonym",
"synonyms": [
"quick,fast"
]
},
"multiplexer_filter": {
"type": "multiplexer",
"filters": ["english_stemmer", "synonym_filter"],
"preserve_original": true
}
},
"analyzer": {
"multiplexer_analyzer": {
"type": "custom",
"tokenizer": "standard",
"filter": [
"multiplexer_filter"
]
}
}
}
}
}
Generated tokens
Use the following request to examine the tokens generated using the analyzer:
POST /multiplexer_index/_analyze
{
"analyzer": "multiplexer_analyzer",
"text": "The slow turtle hides from the quick dog"
}
The response contains the generated tokens:
{
"tokens": [
{
"token": "The",
"start_offset": 0,
"end_offset": 3,
"type": "<ALPHANUM>",
"position": 0
},
{
"token": "slow",
"start_offset": 4,
"end_offset": 8,
"type": "<ALPHANUM>",
"position": 1
},
{
"token": "turtle",
"start_offset": 9,
"end_offset": 15,
"type": "<ALPHANUM>",
"position": 2
},
{
"token": "turtl",
"start_offset": 9,
"end_offset": 15,
"type": "<ALPHANUM>",
"position": 2
},
{
"token": "hides",
"start_offset": 16,
"end_offset": 21,
"type": "<ALPHANUM>",
"position": 3
},
{
"token": "hide",
"start_offset": 16,
"end_offset": 21,
"type": "<ALPHANUM>",
"position": 3
},
{
"token": "from",
"start_offset": 22,
"end_offset": 26,
"type": "<ALPHANUM>",
"position": 4
},
{
"token": "the",
"start_offset": 27,
"end_offset": 30,
"type": "<ALPHANUM>",
"position": 5
},
{
"token": "quick",
"start_offset": 31,
"end_offset": 36,
"type": "<ALPHANUM>",
"position": 6
},
{
"token": "fast",
"start_offset": 31,
"end_offset": 36,
"type": "SYNONYM",
"position": 6
},
{
"token": "dog",
"start_offset": 37,
"end_offset": 40,
"type": "<ALPHANUM>",
"position": 7
}
]
}