How to boost the closest created_at field in Elasticsearch? - ruby-on-rails

Question

I want to sort my query results following some boost rules and in the same time i want them to be sorted as possible by creation date, if i add a created_at sort, it changes everything and my results are not relevant anymore. So i guess the only way to do that is to boost created_at field (the newest has the biggest bonus in calculating score for that boost) but i dont know how to implement it. This is my query:
query = {
"query" : {
"bool" : {
"must" : [
{
"range" : {
"deadline" : {
"gte" : "2016-05-30T11:39:10+02:00"
}
}
},
{
"terms" : {
"state" : [
"open"
]
}
},
{
"query_string" : {
"query" : "chant",
"default_operator" : "AND",
"analyzer" : "search_francais",
"fields" : [
"title^6",
"description",
"brand",
"category_name"
]
}
}
]
}
},
"filter" : {
"and" : [
{
"geo_distance" : {
"distance" : "40km",
"location" : {
"lat" : 48.855736,
"lon" : 2.32927300000006
}
}
}
]
},
"sort" : [
{
"_score" : "desc"
},
#{
# "created_at" : "desc" ==> i tried this but it doesnt change results
#}
]
}

Answer 1

Try adding your condition in should block.
i)If the created date should be closer to come value in the search query or you have any idea on how close the date should be, give a range query.
ii) If you are not sure of all those values, decay function can be used. In this case, query shall be changed to function query.
{
"query" : {
"bool" : {
"must" : [
{
"range" : {
"deadline" : {
"gte" : "2016-05-30T11:39:10+02:00"
}
}
},
{
"terms" : {
"state" : [
"open"
]
}
},
{
"query_string" : {
"query" : "chant",
"default_operator" : "AND",
"analyzer" : "search_francais",
"fields" : [
"title^6",
"description",
"brand",
"category_name"
]
}
}
],
"should": [
{"created_at" : "condition here .. "}
]
}
},
"filter" : {
"and" : [
{
"geo_distance" : {
"distance" : "40km",
"location" : {
"lat" : 48.855736,
"lon" : 2.32927300000006
}
}
}
]
}
}