基于变量和键匹配的数组返回对象

Question

如果对象与变量值匹配，则尝试从数组中提取对象。用户传递存储在名为vars.author的变量中的作者名称。然后，我希望将该值与数组中的author键匹配，并返回包含该值的对象。

{
   "catalog": {
      "book": [
         {
            "author": "Ralls, Kim",
            "title": "Midnight Rain",
            "genre": "Fantasy",
            "price": "5.95",
            "publish_date": "2000-12-16",
            "description": "A former architect battles corporate zombies, \n      an evil sorceress, and her own childhood to become queen \n      of the world.",
            "_id": "bk102"
         },
         {
            "author": "Corets, Eva",
            "title": "Maeve Ascendant",
            "genre": "Fantasy",
            "price": "5.95",
            "publish_date": "2000-11-17",
            "description": "After the collapse of a nanotechnology \n      society in England, the young survivors lay the \n      foundation for a new society.",
            "_id": "bk103"
         },
         {
            "author": "Corets, Eva",
            "title": "Oberon's Legacy",
            "genre": "Fantasy",
            "price": "5.95",
            "publish_date": "2001-03-10",
            "description": "In post-apocalypse England, the mysterious \n      agent known only as Oberon helps to create a new life \n      for the inhabitants of London. Sequel to Maeve \n      Ascendant.",
            "_id": "bk104"
         },
         {
            "author": "Galos, Mike",
            "title": "Visual Studio 7: A Comprehensive Guide",
            "genre": "Computer",
            "price": "49.95",
            "publish_date": "2001-04-16",
            "description": "Microsoft Visual Studio 7 is explored in depth,\n      looking at how Visual Basic, Visual C++, C#, and ASP+ are \n      integrated into a comprehensive development \n      environment.",
            "_id": "bk112"
         }
      ]
   }
}

因此，假设vars.author包含"Corets，Eva“值，我想返回以下内容：

{
            "author": "Corets, Eva",
            "title": "Maeve Ascendant",
            "genre": "Fantasy",
            "price": "5.95",
            "publish_date": "2000-11-17",
            "description": "After the collapse of a nanotechnology \n      society in England, the young survivors lay the \n      foundation for a new society.",
            "_id": "bk103"
         },
         {
            "author": "Corets, Eva",
            "title": "Oberon's Legacy",
            "genre": "Fantasy",
            "price": "5.95",
            "publish_date": "2001-03-10",
            "description": "In post-apocalypse England, the mysterious \n      agent known only as Oberon helps to create a new life \n      for the inhabitants of London. Sequel to Maeve \n      Ascendant.",
            "_id": "bk104"
         },

我试过以下几种不同的方法，但都没有用。我看过这里，但没有完全吻合的地方。如果有人能告诉我一个已经在这里问过的问题，或者可以自己帮我，我会很感激的。谢谢你的帮助。

payload.catalog.book
   filter ((item, index) -> item.author == vars.author) 
    map ((item, index) -> item.author)

更新:通过下面的回复找到解决方案。谢谢大家。

payload filter ($.author == vars.author) map {
    author: $.author,
    title: $.title,
    genre: $.genre,
    price: $.price,
    publish_date: $.publish_date,
    description: $.description,
    id: $."_id"
}

Answer 1

正如Aled所提到的，输出不是一个对象，而是一个数组。要使需求返回包含该值的对象，您必须在流程中使用foreach，然后发送每个对象。

而且就像卡蒂克说的，你不必在下面的地图上工作，

payload.catalog.book过滤器((项，索引) -> item.author == vars.author)

产出：

{“作者”："Corets，Eva"，“标题”："Maeve Ascendant"，“类别”："Fantasy"，"_id"："5.95"，"bk103“："2000-11-17"，"description"：”在英国纳米技术社会崩溃后，年轻的幸存者为一个新社会奠定了基础“，”_id“：”bk103“}，{”作者“："Corets，Eva"，“标题”：“奥伯伦的遗产”、“流派”、“幻想”、“价格”："5.95“、"publish_date"："2001-03-10”、“描述”：“在英国启示录后，只被称为奥伯伦的神秘\n特工帮助伦敦居民创造了新的生活。”“，”，"_id"："bk104“}

Answer 2

响应似乎是您的脚本，没有最终的地图。它将返回与作者名称上的条件匹配的输入数组的项数组。

注意，输出不是一个对象，而是一个数组，因为有多个可能的匹配。您可以将其转换为对象(例如，使用reduce )，但是您需要向每个值添加一个键。