ElasticSearch排序与条件嵌套

Question

使用ElasticSearch我想插入一个条件来排序嵌套字段。

我有这个映射

{
  "dario": {
    "mappings": {
      "agents": {
        "properties": {
          "applications": {
            "type": "nested",
            "properties": {
              "companies": {
                "type": "nested",
                "properties": {
                  "active": {
                    "type": "integer"
                  },
                  "application_date": {
                    "type": "date",
                    "format": "strict_date_optional_time||epoch_millis"
                  },
                  "application_date_month": {
                    "type": "date",
                    "format": "yyyy-MM"
                  },
                  "application_id": {
                    "type": "long"
                  },
                  "assigned_date": {
                    "type": "date",
                    "format": "strict_date_optional_time||epoch_millis"
                  },
                  "buy_date": {
                    "type": "date",
                    "format": "strict_date_optional_time||epoch_millis"
                  },
                  "date": {
                    "type": "date",
                    "format": "strict_date_optional_time||epoch_millis"
                  },
                  "date_month": {
                    "type": "date",
                    "format": "yyyy-MM"
                  },
                  "favorite": {
                    "type": "integer"
                  },
                  "id": {
                    "type": "long"
                  },
                  "notes": {
                    "type": "nested",
                    "properties": {
                      "date": {
                        "type": "date",
                        "format": "strict_date_optional_time||epoch_millis"
                      },
                      "id": {
                        "type": "integer"
                      },
                      "note": {
                        "type": "string",
                        "analyzer": "standard"
                      }
                    }
                  },
                  "score": {
                    "type": "long"
                  },
                  "state": {
                    "type": "long"
                  },
                  "view": {
                    "type": "integer"
                  },
                  "visible": {
                    "type": "integer"
                  },
                  "visible_date": {
                    "type": "date",
                    "format": "strict_date_optional_time||epoch_millis"
                  }
                }
              },
              "count": {
                "type": "integer"
              },
              "sectors": {
                "type": "long"
              }
            }
          }
        }
      }
    }
  }
}

我想按字段applications.companies.buy_date排序，但是，如果这是null，那么我想考虑applications.companies.date 我尝试使用groovy脚本：

{
  "size": 10,
  "from": 0,
  "sort": [
    {
      "_script": {
        "script": "doc['applications.companies.buy_date'] != null ? doc['applications.companies.buy_date'].date.getMillisOfDay() : doc['applications.companies.date'].date.getMillisOfDay()",
        "type": "number",
        "nested_filter": {
          "match": {
            "applications.companies.id": 711
          }
        },
        "order": "desc"
      }
    }
  ],
  "query": {
    "bool": {
      "filter": [
        {
          "bool": {
            "must": [
              {
                "bool": {
                  "must": [
                    {
                      "nested": {
                        "path": "applications.companies",
                        "query": {
                          "bool": {
                            "must": [
                              {
                                "match": {
                                  "applications.companies.active": 1
                                }
                              },
                              {
                                "match": {
                                  "applications.companies.id": 711
                                }
                              },
                              {
                                "bool": {
                                  "should": [
                                    {
                                      "exists": {
                                        "field": "applications.companies.buy_date"
                                      }
                                    },
                                    {
                                      "match": {
                                        "applications.companies.favorite": 1
                                      }
                                    }
                                  ]
                                }
                              }
                            ]
                          }
                        }
                      }
                    }
                  ]
                }
              }
            ]
          }
        }
      ]
    }
  }
}

但没有任何改变。有什么想法吗？

更新

我解决了此解决方案的问题

{
  "size": 10,
  "from": 0,
  "_source": [
    "id"
  ],
  "sort": [
    {
      "_script": {
        "script": {
          "script": " if (doc['applications.companies.id'].value == 711) { return (doc['applications.companies.buy_date'].value > 0) ? doc['applications.companies.buy_date'].value : doc['applications.companies.date'].value; } else { return null; } ",
          "lang": "groovy"
        },
        "type": "number",
        "order": "desc",
        "nested_path": "applications.companies",
        "nested_filter": {
          "match": {
            "applications.companies.id": 711
          }
        }
      }
    }
  ],
  "query": {
    "bool": {
      "filter": [
        {
          "bool": {
            "must": [
              {
                "bool": {
                  "must": [
                    {
                      "nested": {
                        "path": "applications.companies",
                        "query": {
                          "bool": {
                            "must": [
                              {
                                "match": {
                                  "applications.companies.active": 1
                                }
                              },
                              {
                                "match": {
                                  "applications.companies.id": 711
                                }
                              },
                              {
                                "bool": {
                                  "should": [
                                    {
                                      "exists": {
                                        "field": "applications.companies.buy_date"
                                      }
                                    },
                                    {
                                      "match": {
                                        "applications.companies.favorite": 1
                                      }
                                    }
                                  ]
                                }
                              }
                            ]
                          }
                        }
                      }
                    }
                  ]
                }
              }
            ]
          }
        }
      ]
    }
  }
}