feat: Search Service Highlighting

[allisonsuarez]

API highlighting options

Added Optional highlight options to search request, these allow specification of highlights for fields in each resource like:

{
    "results_per_page": 10,
    "page_index": 0,
    "resource_types": [
        "table"
    ],
    "query_term": "amundsen",
    "filters": [],
    "highlight_options": {
        "table": {
            "enable_highlight": true
        }
    }
}

Default highlighting

If "enable_highlight": true is for a resource the default highlight in ES will be:

    "name": {
        "number_of_fragments": 0
    },
    "description": {
        "number_of_fragments": 5,
        "order": "none"
    }

There are other highlights for specific resources like matching columns and column descriptions for tables, and chart and query name highlights for dashboards.

Databuilder dependency

If you are not using the latest mappings from databuilder which include "term_vector" : "with_positions_offsets".