[DOC]Search templates loop works wrong

[SonaGharibyan]

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Having issues with using search templates loops https://opensearch.org/docs/latest/search-plugins/search-template/#loops
I have this query

{
   "source":{
    "query":{
      "bool":{
         "filter":[
            {
               "terms":{
                  "field":["{{#names}}","{{.}}","{{/names}}","3"]
               }
            }
         ]
      }
   }
},
   "params":{
      "names":["1", "2"]
   }
}

which should return items where "field" equals to "1", "2" or "3". But it also return items where "field" is to empty string ("").

Is there another way to destruct "names" array?
pls update docs accordingly

What other resources are available? Provide links to related issues, POCs, steps for testing, etc.
Found similar question just from Elastic Search -> https://stackoverflow.com/questions/67590223/how-to-pass-array-to-elasticsearch-search-template-using-mustache

[kolchfa-aws]

@SonaGharibyan Can you try passing 1 and 2 as strings:
"params":{ "names":["1", "2"] }
And also passing the whole query as a string in the "source" parameter. (Note the format in this section).

[SonaGharibyan]

@kolchfa-aws Yes sorry regarding "params" it was a typo I've updated it. And I've also tried to pass "source" as a string parameter and it also returns all the values where "team" filed (in this example) is empty string ("").

{
  "source": "{\"query\":{\"terms\":{\"team\":[\"{{#myTeams}}\",\"{{.}}\",\"{{/myTeams}}\"]}}}",
  "params": {
    "myTeams":  ["Team A", "Team C"]
  }
}

[kolchfa-aws]

@SonaGharibyan Mustache inserts a comma after every array element so you're getting a match on a phantom empty element produced by a comma after the last term. To avoid this problem, run the query as follows:

GET _search/template
{
  "source": "{\"query\":{\"terms\":{\"team\":{{#toJson}}myTeams{{/toJson}}}}}",
  "params": {
    "myTeams":  ["Team A", "Team C"]
  }
}

[SonaGharibyan]

@kolchfa-aws but I also need to add extra elements like "3" here

{
   "source":{
    "query":{
      "bool":{
         "filter":[
            {
               "terms":{
                  "field":["{{#names}}","{{.}}","{{/names}}","3"]
               }
            }
         ]
      }
   }
},
   "params":{
      "names":["1", "2"]
   }
}

[kolchfa-aws]

Can you just include "3" as an element of the names array?

[SonaGharibyan]

@kolchfa-aws no, in my case this two data are coming from different places and I don't have access to names array.

[kolchfa-aws]

@opensearch-project/opensearch-core Could someone take a look at this issue please? Thanks!