Issue Using project Field in _msearch with Siren Federate

Siren Federate (Elasticsearch Plugin)
1

Hi,
I’m using the Siren Federate plugin and encountering an issue with multi-search (_msearch) queries.

When I use a regular _search query, I can project fields without any problems. However, when I use the same query in _msearch, I get the following error:

{ "index": "user" }
{ "size": 0, "track_total_hits": true, "query": {  "bool":  {  "filter":  [  {  "bool":  {  "must":  [  {  "query_string":  {  "query":  "_exists_:link"  }  }  ]  }  },  {  "bool":  {  "must":  [  {  "join":  {  "indices":  [  "user_info"  ],  "on":  [  "id",  "id"  ],  "request":  {  "query":  {  "bool":  { "must_not":  [  {  "ids":  {  "values":  [  "123"  ]  }  }  ]  }  },  "project":  [  {  "field":  {  "name":  "_score",  "alias":  "sub_score"  }  }  ]  }  }  }  ]  }  }  ],  "must":  [  {  "function_score":  {  "functions":  [  {  "field_value_factor":  {  "field":  "sub_score",  "factor":  1,  "missing":  1  }  }  ]  }  }  ]  }  } }

{
  "error": {
    "root_cause": [
      {
        "type": "parsing_exception",
        "reason": "Unknown key for a START_ARRAY in [project].",
        "line": 824,
        "col": 52
      }
    ],
    "type": "x_content_parse_exception",
    "reason": "[824:52] [bool] failed to parse field [filter]",
    "caused_by": {
      "type": "x_content_parse_exception",
      "reason": "[824:52] [bool] failed to parse field [must]",
      "caused_by": {
        "type": "parsing_exception",
        "reason": "Unknown key for a START_ARRAY in [project].",
        "line": 824,
        "col": 52
      }
    }
  },
  "status": 400
}

I wanted to ask if projection in _msearch requires a special structure or has any limitations, or if this might be an issue with the Siren Federate plugin itself.

Any guidance or example queries would be greatly appreciated.

2

Hello,

There is indeed a bug with msearch. Until the fix is there, just wrap the project into an ext yourself. See edited request:

{"index":"user"}
{"size":0,"track_total_hits":true,"query":{"bool":{"filter":[{"bool":{"must":[{"query_string":{"query":"_exists_:link"}}]}},{"bool":{"must":[{"join":{"indices":["user_info"],"on":["id","id"],"request":{"query":{"bool":{"must_not":[{"ids":{"values":["123"]}}]}},"ext":{"project":[{"field":{"name":"_score","alias":"sub_score"}}]}}}}]}}],"must":[{"function_score":{"functions":[{"field_value_factor":{"field":"sub_score","factor":1,"missing":1}}]}}]}}}

Thanks for bringing this to our attention!

1 Like
3

Hi again, dear friend!
It worked
I can’t tell you how helpful this was. I really, really appreciate it.

1 Like
4

A fix is available in the 39 release Downloads - SIREN of Federate