Elasticsearch advanced autocomplete - elasticsearch

Question

I want to autocomplete user input with Elasticsearch. Now There are tons of tutorials out there how to do so, but none go into the really detailed stuff.
The last issue I'm having with my query is that it should score Results that are not real "autocompletions" lower. Example:
IS:
I type: "Bed"
I find: "Bed", "Bigbed", "Fancy Bed", "Bed Frame"
WANT:
I type: "Bed"
I find: "Bed", "Bed Frame", [other "Bed XXX" results], "Fancy Bed", "Bigbed"
So i want Elasticsearch to first complete "to the right" if that makes sense. And then use results that have words in front of it.
I've tried the completion suggester I doesn't do other stuff I want but also has the same issue.
In German there are lots of examples of words like Bigbed (which isn't a real word in English, I know. But I don't want those words as high results. But since they match closer than Bed Frame (because that is 2 Tokens) they show up so high.
This is my query currently:
POST autocompletion/_search?pretty
{
"query": {
"function_score": {
"query": {
"match": {
"keyword": {
"query": "Bed",
"fuzziness": 1,
"minimum_should_match": "100%"
}
}
},
"field_value_factor": {
"field": "bias",
"factor": 1
}
}
}
}

Answer 1

If you use elasticsearch completion suggester, as explained at https://www.elastic.co/guide/en/elasticsearch/reference/current/search-suggesters-completion.html, when querying like:
{
"suggest": {
"song-suggest" : {
"prefix" : "bed",
"completion" : {
"field" : "suggest"
}
}
}
}
You will get:
{
"took": 13,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"skipped": 0,
"failed": 0
},
"hits": {
"total": 0,
"max_score": 0.0,
"hits": []
},
"suggest": {
"song-suggest": [
{
"text": "bed",
"offset": 0,
"length": 3,
"options": [
{
"text": "Bed",
"_index": "autocomplete",
"_type": "_doc",
"_id": "1",
"_score": 34.0,
"_source": {
"suggest": {
"input": [
"Bed"
],
"weight": 34
}
}
},
{
"text": "Bed Frame",
"_index": "autocomplete",
"_type": "_doc",
"_id": "3",
"_score": 34.0,
"_source": {
"suggest": {
"input": [
"Bed Frame"
],
"weight": 34
}
}
}
]
}
]
}
}
If you want to use the search API instead, you can use 2 queries:
prefix query "bed ****"
with a term starting by "bed"
Here the mapping:
{
"mappings": {
"_doc" : {
"properties" : {
"suggest" : {
"type" : "text",
"fields" : {
"keyword" : {
"type" : "keyword"
}
}
}
}
}
}
Here the search query:
{
"query" : {
"bool" : {
"must" : [
{
"match" : {
"suggest" : "Bed"
}
}
],
"should" : [
{
"prefix" : {
"suggest.keyword" : "Bed"
}
}
]
}
}
}
The should clause will boost document starting by "Bed". Et voilà!