Mixing bool and multi match/function score query

Question

I'm currently doing a query that's a mix of multi match and function score. The important bit of the JSON looks like this:

"function_score":{
    "query":{
        "query_string":{
            "query":"some query",
            "fields":["id","name","strippedDescription","colourSearch","sizeSearch"]
        }
    }
}

However, I also want to include results that don't necessarily match the query but have a particular numeric value that's greater than 0. I think a bool query would do this, but I don't know how to use a bool query with a function score query.

I understand that a multi match query is just shorthand for a bool query, and I could expand out the multi match query into its bool counter-part, however, I then don't know how I would do function score within that.

Any ideas? I'm on version 1.1.0 by the way.

Answer 1

Figured it out! I was missing the fact that you can nest multi field queries within bool queries! My final solution looks like this:

{
    "query":{
        "function_score":{
            "query":{
                "bool":{
                    "should": [
                       {
                           "range": {
                              "allBoost": {
                                 "gt": 0
                              }
                           }
                       },{
                            "multi_match":{
                                "query":"some search query",
                                "fields":[
                                    "id",
                                    "name",
                                    "description",
                                    "category"
                                ]
                            }
                       }
                    ]
                }
            },
            "functions":[
                {
                    "filter":{
                        "range": {
                            "allBoost": {
                                "gt": 0
                            }
                        }
                    },
                    "script_score":{
                        "script":"doc['allBoost'].value"
                    }
                },
                {
                    "filter":{
                        "range": {
                            "allBoost": {
                                "lte": 0
                            }
                        }
                    },
                    "script_score":{
                        "script":"_score"
                    }
                }
            ],
            "boost_mode": "replace"
        }
    }
}