PhraseSuggestCollate needs a Params property to pass params to the collate query

[tsquires]

NEST/ElasticSearch.Net 5.3
Elasticsearch 5.5

When running a collate query on a phrase suggester the json produced and sent to the server looks like this with the params object inside of the query object:

        "collate": {
          "query": {
            "inline": "{\"bool\":{\"must\":[{\"match\":{\"{{field-name}}\":{\"query\":\"{{suggestion}}\",\"type\":\"phrase\"}}}],\"filter\":[{\"nested\":{\"query\":{\"bool\":{\"filter\":[{\"term\":{\"listings.site-ids\":{\"value\":\"{{site-id}}\"}}},{\"term\":{\"listings.region-id\":{\"value\":\"{{region-id}}\"}}},{\"term\":{\"listings.industry-id\":{\"value\":\"{{industry-id}}\"}}}]}},\"path\":\"listings\"}},{\"bool\":{\"must_not\":[{\"exists\":{\"field\":\"private-ids\"}}]}}]}}}",
            "params": {
              "field-name": "name",
              "site-id": "1",
              "region-id": "1",
              "industry-id": "4"
            }
          },
          "prune": true
        }

While a working query when setting up the json manually looks like this with the params object inside of the collate object instead:

        "collate": {
        	"query": {
        		"inline": "{\"bool\":{\"must\":[{\"match\":{\"{{field-name}}\":{\"query\":\"{{suggestion}}\",\"type\":\"phrase\"}}}],\"filter\":[{\"nested\":{\"query\":{\"bool\":{\"filter\":[{\"term\":{\"listings.site-ids\":{\"value\":\"{{site-id}}\"}}},{\"term\":{\"listings.region-id\":{\"value\":\"{{region-id}}\"}}},{\"term\":{\"listings.industry-id\":{\"value\":\"{{industry-id}}\"}}}]}},\"path\":\"listings\"}},{\"bool\":{\"must_not\":[{\"exists\":{\"field\":\"private-ids\"}}]}}]}}"
        	},
        	"params": {
        		"field-name": "name",
        		"site-id": "1",
        		"region-id": "1",
        		"industry-id": "4"
        		},
        	"prune": true
        }

Steps to reproduce:

1. Setup a phrase suggester in json with a collate query that takes parameters
2. Setup the same phrase suggester in .Net
3. Compare the request body of the .Net request to the json from Step 1 and see the params object is at the wrong level so in the .Net request the params are not replaced in the collate query

Adding a Params property to PhraseSuggestCollate fixes this and produces a working request.

[russcam]

Thanks for opening @tsquires; apologies it's taken a while to respond. Looking at this now