context suggester

context_suggester

# create an index called "services" with suggest_field mapped as "completion" with payloads
POST services
{
  "mappings": {
    "service": {
      "properties": {
        "name": {
          "type": "string"
        },
        "suggest_field": {
          "type": "completion",
          "payloads": true,
          "context": {
            "color": {
              "type": "category"
            }
          }
        }
      }
    }
  }
}

# index a document with id = 1. The input of the completion is "same_input" with 
# weight = 100 and payload {"url": "first_document"}
PUT services/service/1
{
    "name": "same_input",
    "suggest_field": {
        "input": "same_input",
        "weight": 100,
        "payload": {
          "url": "first_document"
        },
        "context": {
            "color": ["red", "yellow"]
        }
    }
}

# index a document with id = 2. The input of the completion is "same_input" too with 
# weight = 200 and payload {"url": "second_document"}
PUT services/service/2
{
    "name": "same_input",
    "suggest_field": {
        "input": "same_input",
        "weight": 200,
        "payload": {
          "url": "second_document"
        },
        "context": {
            "color": ["red", "green"]
        }
    }
}

# query for suggest using "same_input" as text
POST services/_suggest?pretty'
{
    "suggest" : {
        "text" : "same_input",
        "completion" : {
            "field" : "suggest_field",
            "size": 10,
            "context": {
                "color": ["red"]
            }
        }
    }
}

# the response includes only one document with the score 200, which is the 
# weigth of the document id = 2 but with the payload of the document 
# of id = 1 when using context "red".
{
   "_shards": {
      "total": 5,
      "successful": 5,
      "failed": 0
   },
   "suggest": [
      {
         "text": "same_input",
         "offset": 0,
         "length": 10,
         "options": [
            {
               "text": "same_input",
               "score": 200,
               "payload": {
                  "url": "first_document"
               }
            }
         ]
      }
   ]
}