Retrieve object with a matching attribute in an array - Elasticsearch

As I am understanding, you want to retrieve document with variants items which has price of "82.00" i.e. variant - "Concrete blue - 71y-9a6" and not "Concrete teal - oxh-g1z" in document above.

In a regular scenario, if you search for document with variant price "82.00", it will find and return all document that match variant price and as well as other variants item in array which price is not "82.00".

{
    "query" : {
        "match":{
            "variants.price" :"82.00"
        }
    }
}

//Will return above document with variants items both "Concrete blue - 71y-9a6" and "Concrete teal - oxh-g1z". 

However, if you want to retrieve only variant item with price "82.00", you need to able to query that variant item separately and the solution is to use nested datatype in your doucument mapping.

The nested type is a specialized version of the object datatype that allows arrays of objects to be indexed and queried independently of each other.

{
  "mappings": {
    "foo": {
      "properties": {
        "createdAt": {
          "type": "date"
        },
        "description": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "descriptionHtml": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "handle": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "id": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "options": {
          "properties": {
            "id": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "name": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "values": {
              "properties": {
                "value": {
                  "type": "text",
                  "fields": {
                    "keyword": {
                      "type": "keyword",
                      "ignore_above": 256
                    }
                  }
                }
              }
            }
          }
        },
        "productType": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "publishedAt": {
          "type": "date"
        },
        "tags": {
          "properties": {
            "value": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            }
          }
        },
        "title": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        },
        "updatedAt": {
          "type": "date"
        },
        "variants": {
          "type": "nested",
          "properties": {
            "available": {
              "type": "boolean"
            },
            "id": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "price": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "product": {
              "properties": {
                "id": {
                  "type": "text",
                  "fields": {
                    "keyword": {
                      "type": "keyword",
                      "ignore_above": 256
                    }
                  }
                }
              }
            },
            "selectedOptions": {
              "properties": {
                "name": {
                  "type": "text",
                  "fields": {
                    "keyword": {
                      "type": "keyword",
                      "ignore_above": 256
                    }
                  }
                },
                "value": {
                  "type": "text",
                  "fields": {
                    "keyword": {
                      "type": "keyword",
                      "ignore_above": 256
                    }
                  }
                }
              }
            },
            "sku": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "title": {
              "type": "text",
              "fields": {
                "keyword": {
                  "type": "keyword",
                  "ignore_above": 256
                }
              }
            },
            "weight": {
              "type": "long"
            }
          }
        },
        "vendor": {
          "type": "text",
          "fields": {
            "keyword": {
              "type": "keyword",
              "ignore_above": 256
            }
          }
        }
      }
    }
  }
}

Querying your document:

{
  "query": {
    "nested": {
      "path": "variants",
      "query": {
        "match": {
          "variants.price": "82.00"
        }
      },
      "inner_hits": {}
    }
  }
}

In above query, the variants nested field is explicitly queried with variant price "82.00". Note that, inner_hits allow us to highlight the matching nested documents because, elastic return the complete document along with all variant items, the inner_hits will contains only matched variant item (this is what we need). Also, you can limit field projection with _source (e.g. you may not want variants field root document but only variant items in inner_hits).

{
  "took": 45,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 0.6931472,
    "hits": [
      {
        "_index": "foo",
        "_type": "foo",
        "_id": "1",
        "_score": 0.6931472,
        "_source": {
          "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0LzIyODA5MjA1MTQ4NQ==",
          "createdAt": "2017-10-23T11:05:40Z",
          "updatedAt": "2018-03-10T05:24:40Z",
          "descriptionHtml": "Et blanditiis autem. Molestiae delectus vero voluptatem libero cum. Aliquam tempore ex id sed aut excepturi facilis sunt.",
          "description": "Et blanditiis autem. Molestiae delectus vero voluptatem libero cum. Aliquam tempore ex id sed aut excepturi facilis sunt.",
          "handle": "future-proofed-re-engineered-handmade-cotton-chicken",
          "productType": "Computers",
          "title": "Future-proofed Re-engineered Handmade Cotton Chicken",
          "vendor": "Bednar LLC",
          "tags": [
            {
              "value": "data-generator"
            }
          ],
          "publishedAt": "2018-03-07T08:25:38Z",
          "onlineStoreUrl": null,
          "options": [
            {
              "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0T3B0aW9uLzM2NTQ0NDI2ODA2MQ==",
              "name": "Title",
              "values": [
                {
                  "value": "Concrete blue - 71y-9a6"
                },
                {
                  "value": "Concrete teal - oxh-g1z"
                }
              ]
            }
          ],
          "images": [],
          "variants": [
            {
              "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0VmFyaWFudC8zMzczOTAzODcyMDI5",
              "title": "Concrete blue - 71y-9a6",
              "price": "82.00",
              "weight": 14,
              "available": true,
              "sku": "",
              "compareAtPrice": null,
              "image": null,
              "selectedOptions": [
                {
                  "name": "Title",
                  "value": "Concrete blue - 71y-9a6"
                }
              ],
              "product": {
                "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0LzIyODA5MjA1MTQ4NQ==",
                "images": []
              }
            },
            {
              "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0VmFyaWFudC8zMzczOTA0MDAzMTAx",
              "title": "Concrete teal - oxh-g1z",
              "price": "196.00",
              "weight": 7,
              "available": true,
              "sku": "",
              "compareAtPrice": null,
              "image": null,
              "selectedOptions": [
                {
                  "name": "Title",
                  "value": "Concrete teal - oxh-g1z"
                }
              ],
              "product": {
                "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0LzIyODA5MjA1MTQ4NQ==",
                "images": []
              }
            }
          ]
        },
        "inner_hits": {
          "variants": {
            "hits": {
              "total": 1,
              "max_score": 0.6931472,
              "hits": [
                {
                  "_nested": {
                    "field": "variants",
                    "offset": 0
                  },
                  "_score": 0.6931472,
                  "_source": {
                    "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0VmFyaWFudC8zMzczOTAzODcyMDI5",
                    "title": "Concrete blue - 71y-9a6",
                    "price": "82.00",
                    "weight": 14,
                    "available": true,
                    "sku": "",
                    "compareAtPrice": null,
                    "image": null,
                    "selectedOptions": [
                      {
                        "name": "Title",
                        "value": "Concrete blue - 71y-9a6"
                      }
                    ],
                    "product": {
                      "id": "Z2lkOi8vc2hvcGlmeS9Qcm9kdWN0LzIyODA5MjA1MTQ4NQ==",
                      "images": []
                    }
                  }
                }
              ]
            }
          }
        }
      }
    ]
  }
}