Multiplexer token filter
editMultiplexer token filter
editA token filter of type multiplexer
will emit multiple tokens at the same position,
each version of the token having been run through a different filter. Identical
output tokens at the same position will be removed.
If the incoming token stream has duplicate tokens, then these will also be removed by the multiplexer
Options
edit
filters |
a list of token filters to apply to incoming tokens. These can be any
token filters defined elsewhere in the index mappings. Filters can be chained
using a comma-delimited string, so for example |
Shingle or multi-word synonym token filters will not function normally when they are declared in the filters array because they read ahead internally which is unsupported by the multiplexer
- preserve_original
-
if
true
(the default) then emit the original token in addition to the filtered tokens
Settings example
editYou can set it up like:
PUT /multiplexer_example { "settings": { "analysis": { "analyzer": { "my_analyzer": { "tokenizer": "standard", "filter": [ "my_multiplexer" ] } }, "filter": { "my_multiplexer": { "type": "multiplexer", "filters": [ "lowercase", "lowercase, porter_stem" ] } } } } }
And test it like:
POST /multiplexer_example/_analyze { "analyzer" : "my_analyzer", "text" : "Going HOME" }
And it’d respond:
{ "tokens": [ { "token": "Going", "start_offset": 0, "end_offset": 5, "type": "<ALPHANUM>", "position": 0 }, { "token": "going", "start_offset": 0, "end_offset": 5, "type": "<ALPHANUM>", "position": 0 }, { "token": "go", "start_offset": 0, "end_offset": 5, "type": "<ALPHANUM>", "position": 0 }, { "token": "HOME", "start_offset": 6, "end_offset": 10, "type": "<ALPHANUM>", "position": 1 }, { "token": "home", "start_offset": 6, "end_offset": 10, "type": "<ALPHANUM>", "position": 1 } ] }
The stemmer has also emitted a token |
The synonym and synonym_graph filters use their preceding analysis chain to parse and analyse their synonym lists, and will throw an exception if that chain contains token filters that produce multiple tokens at the same position. If you want to apply synonyms to a token stream containing a multiplexer, then you should append the synonym filter to each relevant multiplexer filter list, rather than placing it after the multiplexer in the main token chain definition.