Continuation of the question Elasticsearch: Influence scoring with custom score field in document pt.2
It all works ok as @Joanna's answer. I just want to add decay function to the query:
{
"query": {
"function_score": {
"query": {
"bool": {
"should": [{
"nested": {
"path": "tags",
"score_mode": "sum",
"query": {
"function_score": {
"query": {
"match": {
"tags.tag": "landscape"
}
},
"field_value_factor": {
"field": "tags.confidence",
"factor": 1,
"missing": 0
}
}
}
}
}]
}
},
"field_value_factor": {
"field": "boost_multiplier",
"factor": 1,
"missing": 0
}
}
}
}
based on the created_at field of the document:
{
"created_at" : "2017-07-31T20:30:14-04:00",
"description" : null,
"height" : 3213,
"id" : "1",
"tags" : [
{
"confidence" : 65.48948436785749,
"tag" : "beach"
},
{
"confidence" : 57.31950504425406,
"tag" : "sea"
},
{
"confidence" : 43.58207236617374,
"tag" : "coast"
},
{
"confidence" : 35.6857910950816,
"tag" : "sand"
},
{
"confidence" : 33.660057321079655,
"tag" : "landscape"
},
{
"confidence" : 32.53252312423727,
"tag" : "sky"
}
],
"width" : 5712,
"color" : "#0C0A07",
"boost_multiplier" : 1
}
I found this in the documentation: https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-function-score-query.html#function-decay
I tried to add the gauss function as shown in the example in the documentation as sibling to inner "field_value_factor", and it gives error saying "failed to parse [function_score] query. already found function [field_value_factor], now encountering [gauss]. use [functions] array if you want to define several functions.".
Then I put both "field_value_factor", and "gauss" under functions array inside inner "query", this time I get error saying "failed to parse [START_OBJECT]. malformed query, expected a [VALUE_STRING] while parsing functions but got a [function_score] instead".
Simply I can't find where to put the "gauss" function in the query to use decaying based on created_at field.
UPDATE I also tried the below query:
{
"query": {
"function_score": {
"query": {
"bool": {
"should": [{
"nested": {
"path": "tags",
"score_mode": "sum",
"query": {
"function_score": {
"query": {
"match": {
"tags.tag": "landscape city"
}
},
"field_value_factor": {
"field": "tags.confidence",
"factor": 5,
"missing": 0
}
}
}
}
}]
}
},
"functions": [
{
"decay": {
"gauss": {
"created_at": {
"origin": "2013-09-17",
"scale": "10d",
"offset": "5d",
"decay": 0.5
}
}
}
},
{
"field_value_factor": {
"field": "boost_multiplier",
"factor": 1,
"missing": 0
}
}
]
}
}
}
This time it gives error saying "no [query] registered for [decay]".
Any help?
UPDATE-2 The following query works:
{
"query": {
"function_score": {
"query": {
"bool": {
"should": [{
"nested": {
"path": "tags",
"score_mode": "sum",
"query": {
"function_score": {
"query": {
"match": {
"tags.tag": "landscape city"
}
},
"field_value_factor": {
"field": "tags.confidence",
"factor": 5,
"missing": 0
}
}
}
}
}]
}
},
"functions": [
{
"field_value_factor": {
"field": "boost_multiplier",
"factor": 1,
"missing": 0
}
},
{
"gauss": {
"created_at": {
"scale": "365d",
"offset": "5d",
"decay" : 0.5
}
}
}
]
}
}
}
Works meaning it doesn't give error, but I don't get the result I expected. I simply want to give boost to the recent documents over the older ones. Any help how to achieve it?
