elasticsearch percolator stemmer - elasticsearch

Question

I'm attempting to use the percolation function in elasticsearch. It works great but out of the box there is no stemming to handle singular/plurals etc. The documentation is rather thin on this topic so I was wondering if anyone has gotten this working and what settings are required. At the moment I'm not indexing my documents since I'm not searching them, just passing them through the percolator to trigger notifications.

Answer 1

You can use the percolate API to test documents against percolators without indexing them. However, the percolate API requires and index and a type for your doc. This is so that it knows how each field in your document is defined (or mapped).
Analyzers belong to an index, and the fields in a mapping/type definition can use either globally defined analyzers, or custom analyzers defined for your index.
For instance, we could define a mapping for index test, type test using a globally defined analyzer as follows:
curl -XPUT 'http://127.0.0.1:9200/test/?pretty=1' -d '
{
"mappings" : {
"test" : {
"properties" : {
"title" : {
"type" : "string",
"analyzer" : "english"
}
}
}
}
}
'
Or alternatively, you could setup a custom analyzer that belongs just to the test index:
curl -XPUT 'http://127.0.0.1:9200/test/?pretty=1' -d '
{
"mappings" : {
"test" : {
"properties" : {
"title" : {
"type" : "string",
"analyzer" : "my_english"
}
}
}
},
"settings" : {
"analysis" : {
"analyzer" : {
"my_english" : {
"stopwords" : [],
"type" : "english"
}
}
}
}
}
'
Now we can create our percolator, specifying which index it belongs to:
curl -XPUT 'http://127.0.0.1:9200/_percolator/test/english?pretty=1' -d '
{
"query" : {
"match" : {
"title" : "singular"
}
}
}
'
And test it out with the percolate API, again specifying the index and the type:
curl -XGET 'http://127.0.0.1:9200/test/test/_percolate?pretty=1' -d '
{
"doc" : {
"title" : "singulars"
}
}
'
# {
# "ok" : true,
# "matches" : [
# "english"
# ]
# }