ElasticSearch autocomplete for keywords from a string - autocomplete

Question

My document looks like:
"hits": {
"total": 4,
"max_score": 1,
"hits": [
{
"_index": "test_db2",
"_type": "test",
"_id": "1",
"_score": 1,
"_source": {
"name": "very cool shoes",
"price": 26
}
},
{
"_index": "test_db2",
"_type": "test",
"_id": "2",
"_score": 1,
"_source": {
"name": "great shampoo",
"price": 15
}
},
{
"_index": "test_db2",
"_type": "test",
"_id": "3",
"_score": 1,
"_source": {
"name": "shirt",
"price": 25
}
}
]
}
How to create autocomplete in elasticsearch like for example:
I put in input word "sh" , after that I should see result
shoes
shampoo
shirt
.....
Example of what I need

Answer 1

Take a look at ngrams. Or actually, edge ngrams are probably all you need.
Qbox has a couple of blog posts about setting up autocomplete with ngrams, so for a more in-depth discussion I would refer you to these:
https://qbox.io/blog/an-introduction-to-ngrams-in-elasticsearch
https://qbox.io/blog/multi-field-partial-word-autocomplete-in-elasticsearch-using-ngrams
But just very quickly, this should get you started.
First I set up the index:
PUT /test_index
{
"settings": {
"analysis": {
"analyzer": {
"autocomplete": {
"type": "custom",
"tokenizer": "standard",
"filter": [
"standard",
"stop",
"kstem",
"edgengram_filter"
]
}
},
"filter": {
"edgengram_filter": {
"type": "edgeNGram",
"min_gram": 2,
"max_gram": 15
}
}
}
},
"mappings": {
"doc": {
"properties": {
"name": {
"type": "string",
"index_analyzer": "autocomplete",
"search_analyzer": "standard"
},
"price":{
"type": "integer"
}
}
}
}
}
Then I indexed your documents:
POST /test_index/doc/_bulk
{"index":{"_id":1}}
{"name": "very cool shoes","price": 26}
{"index":{"_id":2}}
{"name": "great shampoo","price": 15}
{"index":{"_id":3}}
{"name": "shirt","price": 25}
Now I can get autocomplete results with a simple match query:
POST /test_index/_search
{
"query": {
"match": {
"name": "sh"
}
}
}
which returns:
{
"took": 3,
"timed_out": false,
"_shards": {
"total": 5,
"successful": 5,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 0.30685282,
"hits": [
{
"_index": "test_index",
"_type": "doc",
"_id": "3",
"_score": 0.30685282,
"_source": {
"name": "shirt",
"price": 25
}
},
{
"_index": "test_index",
"_type": "doc",
"_id": "2",
"_score": 0.19178301,
"_source": {
"name": "great shampoo",
"price": 15
}
},
{
"_index": "test_index",
"_type": "doc",
"_id": "1",
"_score": 0.15342641,
"_source": {
"name": "very cool shoes",
"price": 26
}
}
]
}
}
Here's the code I used to test it:
http://sense.qbox.io/gist/0886488ddfb045c69eed67b15e9734187c8b2491