Highlight tags not working with Percolator - Unified Highlighter

[gmoskovicz]

Elasticsearch version: 5.3.0

Plugins installed: [x-pack]

JVM version: All

OS version: Mac

Description of the problem including expected versus actual behavior:

Steps to reproduce:

[1] Create a test index

DELETE test

PUT test
{
  "settings": {
    "analysis": {
      "normalizer": {
        "lowercase_normalizer": {
          "type": "custom",
          "filter": [
            "lowercase"
          ]
        }
      }
    }
  },
  "mappings": {
    "doctype": {
      "properties": {
        "hashtags": {
          "type": "keyword",
          "normalizer": "lowercase_normalizer"
        }
      }
    },
    "queries": {
      "properties": {
        "query": {
          "type": "percolator"
        }
      }
    }
  }
}

[2] Add a percolator query

POST test/queries
{
  "query": {
    "match": {
      "hashtags": "#thisisthetesthashtag"
    }
  }
}

[3] Perform a search operation with highlighting

GET test/_search
{
  "highlight": {
    "fields": {
      "*": {
        "type": "unified"
      }
    },
    "post_tags": [
      "</highlight>"
    ],
    "pre_tags": [
      "<highlight>"
    ]
  },
  "query": {
    "percolate": {
      "field": "query",
      "document_type": "doctype",
      "document": {
        "hashtags": ["#ThisIsTheTestHashtag"]
      }
    }
  }
}

Result:

{
  "took": 3,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.2876821,
    "hits": [
      {
        "_index": "test",
        "_type": "queries",
        "_id": "AVuM-0xo4UCyeiU_VRN4",
        "_score": 0.2876821,
        "_source": {
          "query": {
            "match": {
              "hashtags": "#thisisthetesthashtag"
            }
          }
        },
        "highlight": {
          "hashtags": [
            "#ThisIsTheTestHashtag"   <--- HIGHLIGHT WORK , WITHOUT post/pre tags
          ]
        }
      }
    ]
  }
}

[jimczi]

This issue is fixed in 6.x, hence closing.