json - 逐 block 解析 JSON

Question

我有一个包含客户和日期列表的 JSON 文件。

文件看起来像这样:

{
"Customers": [
{
  "Customer": "Customer Name Here",
  "Company": "Super Coffee",
  "First Name": "First Name Here",
  "Main Phone": "777-777-7777",
  "Fax": "777-777-7777",
  "Bill to 1": "Billing Address One",
  "Bill to 2": "Billing Address Two",
  "Bill to 3": "Billing Address Three",
  "Ship to 1": "Shipping Address One",
  "Ship to 2": "Shipping Address Two",
  "Ship to 3": "Shipping Address Three",
  "Customer Type": "Dealer/Retail"
},
{
  "Customer": "Customer Name Here",
  "Company": "Turtle Mountain Welding",
  "First Name": "First Name Here",
  "Main Phone": "777-777-7777",
  "Fax": "777-777-7777",
  "Bill to 1": "Billing Address One",
  "Bill to 2": "Billing Address Two",
  "Bill to 3": "Billing Address Three",
  "Ship to 1": "Shipping Address One",
  "Ship to 2": "Shipping Address Two",
  "Ship to 3": "Shipping Address Three",
  "Customer Type": "Dealer/Retail"
},
{
  "Customer": "Customer Name Here",
  "Company": "Mountain Equipment Coop",
  "First Name": "First Name Here",
  "Main Phone": "777-777-7777",
  "Fax": "777-777-7777",
  "Bill to 1": "Billing Address One",
  "Bill to 2": "Billing Address Two",
  "Bill to 3": "Billing Address Three",
  "Ship to 1": "Shipping Address One",
  "Ship to 2": "Shipping Address Two",
  "Ship to 3": "Shipping Address Three",
  "Customer Type": "Dealer/Retail"
},
{
  "Customer": "Customer Name Here",
  "Company": "Best Soup Inc.",
  "First Name": "First Name Here",
  "Main Phone": "777-777-7777",
  "Fax": "777-777-7777",
  "Bill to 1": "Billing Address One",
  "Bill to 2": "Billing Address Two",
  "Bill to 3": "Billing Address Three",
  "Ship to 1": "Shipping Address One",
  "Ship to 2": "Shipping Address Two",
  "Ship to 3": "Shipping Address Three",
  "Customer Type": "Dealer/Retail"
}
]
}

我需要能够逐 block 而不是逐行地从文件中提取数据。

我习惯于逐行解析文件以获取数据，但是对于 JSON，我需要以某种方式逐 block 读取它(或者更准确地说，逐个对象？)。我需要为每个客户阅读括号内的内容。这样我就可以编写一个脚本来提取我需要的数据，并从中构建一个 CSV 文件。

例如:

i="1"
for file in *.json; do
     customername=$(jsonblock$i:customername);
     customerAddress=$(jsonblock$i:customeraddress);
     etc...
     i=$[i+1]
done

我明白在逐行读取文件时这是如何完成的，但是我如何才能读取每个 JSON block ，就好像它是一行一样？

Answer 1

对于上面的 JSON(由于提供的数据无效而进行了修改)，以下脚本将解析并打印每个 block 的 "Company:" 部分:

#!/usr/bin/env perl

use JSON;   
use IO::All;     
use v5.16;

my $data < io 'Our_Customers.json';
my $customers_list = decode_json($data)->{"Customers"};                

for my $customer (@$customers_list) {
   say $customer->{"Company"} ;
}

输出:

Super Coffee
Turtle Mountain Welding
Mountain Equipment Coop
Best Soup Inc.

脚本使用IO::All和 JSON读取和解析 (decode_json) 文件。

在这个例子中，JSON 数据被简单地映射到一个 Perl 数据结构(一个 Array of Hashes )，它与 JSON 数据完全对应。然后我们可以访问每个数组元素(即数组中的每个散列)，然后通过键名访问散列中的数据。 Perl 具有非常灵活的数据处理和访问功能，这使得处理 JSON 数据变得非常愉快。

每个数据 block 的键来自 JSON 文件的等效部分。如果我们将一个元素移出数组，它将是一个散列，我们访问可以看到元素的 keys 和 values，如下所示:

say for keys shift $customers_list ;

Customer Type
First Name
Bill to 2
Main Phone
...

使用您在 for 循环中看到的 $element->{"key"} 语法访问每个键的值。

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最好在将 JSON 数据发布到 SO 之前对其进行验证 - JSON Lint类似的服务可以帮助解决这个问题。