Dynamic Mapping for Nested Type

Question

I am trying to create a dynamic mapping for objects like the following:

  {
    "product": {
        "productId": 99999,
        "manufacturerId": "A0001",
        "manufacturerCode": "A101LI",
        "name": "Test Product",
        "description": "Describe the product here.",
        "feature_details":{
            "category": "Category1",
            "brand": "Brand Name"
        },
        "feature_tpcerts":{
            "certifiedPass": true,
            "levelCertified": 2
        },
        "feature_characteristics":{
            "amount": 0.73,
            "location": 49464
        }
    }
}

I would like the feature_* properties to be a nested type, which I have defined in the mapping below with the nested_feature template and it is working as expected. However, I also want to have each property in the nested object of the feature_*property to be multi_value with an additional facet property defined. I have tried the second nested_template template, but without any success.

 {
    "product" : {
        "_timestamp" : {"enabled" : true, "store": "yes" },
        "dynamic_templates": [
            {
              "nested_feature": {
                "match" : "feature_*",
                "mapping" : {
                  "type" : "nested",
                  "stored": "true"
                }
              }
            },
            {
                "nested_template": {
                    "match": "feature_*.*",
                    "mapping": {
                        "type": "multi_field",
                        "fields": {
                            "{name}": {
                                "type": "{dynamic_type}",
                                "index": "analyzed"
                            },
                            "facet": {
                                "type": "{dynamic_type}",
                                "index": "not_analyzed"
                            }
                        }
                    }
                }
            }           
        ],
        "properties" : {
            "productId" : { "type" : "integer", "store" : "yes"},
            "manufacturerId" : { "type" : "string", "store" : "yes", "index" : "analyzed"},
            "manufacturer" : { "type" : "string", "store" : "yes", "index" : "not_analyzed"},
            "manufacturerCode" : { "type" : "string", "store" : "yes"},
            "name" : {"type" : "string", "store" : "yes"},
            "description": {"type": "string", "index" : "analyzed"}
        }
    }
}

Unfortunately, the properties within the feature_* properties are created from another process and can be almost any name/value pair. Any suggestions on how to use a dynamic template to setup a property as nested as well as make each property within the nested object multi_field with an additional facet property?

Answer 1

You just have to use path_match instead of match when the pattern refers to the whole field path, otherwise only its name (last part) is taken into account. Have a look at the reference page for the root object, which contains also some documentation related to dynamic templates.

You might also want to use match_mapping_type as you can't set "index":"analyzed" for numeric or boolean fields for instance. In that case you might want to do different things depending on the field type.

I noticed that your document contains the product root object, which you don't really need. I would remove it, as the type name is already product.

Also, I would avoid storing fields explicitly unless you really need to, as with elasticsearch you have the _source field stored by default, which is what you are going to need all the time.

The following mapping should work in your case (without the product root object in the documents):

{
      "product" : {
          "dynamic_templates": [
              {
                "nested_feature": {
                  "match" : "feature_*",
                  "mapping" : {
                    "type" : "nested"
                  }
                }
              },
              {
                  "nested_template": {
                      "path_match": "feature_*.*",
                      "match_mapping_type" : "string",
                      "mapping": {
                          "type": "multi_field",
                          "fields": {
                              "{name}": {
                                  "type": "{dynamic_type}",
                                  "index": "analyzed"
                              },
                              "facet": {
                                  "type": "{dynamic_type}",
                                  "index": "not_analyzed"
                              }
                          }
                      }
                  }
              }                
          ]
      }
  }