将多个 jq 值通过管道传输到“while read -r"；环形 [英] Pipe multiple jq values to "while read -r" loop

问题描述

我试图找到一种干净的方法，在 while 循环中将 2 个 json 字符串值分配给 2 个变量.我正在使用的循环和输入如下.

I am trying to find a clean way to assign 2 json string values to 2 variables within a while loop. The loop and input I am working with are as follows.

输入:

foo='
[
   {
      "name":"name string (more info)",
      "nested_name":{
         "name":"my name",
         "conclusion":"failure",
         "number":11
      }
   },
   {
      "name":"name string (more info)",
      "nested_name":{
         "name":"my other name",
         "conclusion":"failure",
         "number":13
      }
   }
]'

目前我有以下几点:

echo "$foo" | jq ".[].name,.[].nested_name.name" | while read -r foo bar; do
    # do stuff with foo and bar
done

在迭代 1 中，我想要:

In iteration 1, I want:

foo = "name string (more info)" 
bar = "my name"

迭代 2:

foo = "name string (more info)" 
bar = "my other name"

然而，这会产生以下不正确的输出:

However this generates the following incorrect output:

foo = "name 
bar = string (more info)"
foo = "name 
bar = string (more info)"
foo = "my 
bar = name"
foo = "my 
bar = other name"

我一整天都在做这件事，非常感谢任何意见或建议！

I've been at this all day, any input or suggestions would be very much appreciated!

推荐答案

使用两个read，每行一个:

#!/usr/bin/env bash

json='
[
   {
      "name":"name string (more info)",
      "nested_name":{
         "name":"my name",
         "conclusion":"failure",
         "number":11
      }
   },
   {
      "name":"name string (more info)",
      "nested_name":{
         "name":"my other name",
         "conclusion":"failure",
         "number":13
      }
   }
]'


while read -r foo && read -r bar; do
    printf "foo=%s\nbar=%s\n" "$foo" "$bar"
done < <(jq ".[] | .name, .nested_name.name" <<<"$json")

---

我不得不改变你的 jq 表达式以获得你想要的输出.

---

I had to change your jq expression to get your desired output.

还要注意对原始 JSON 文本和循环变量使用不同的名称，使用 here string 而不是 echo，并且使用文件重定向而不是管道；如果 while 的主体设置了以后需要的任何变量，则很有用.

Also note using different names for your original JSON text and the loop variable, using a here string instead of echo, and using file redirection instead of a pipeline; useful if the body of the while sets any variables needed later.

另一种方法是将所有 jq 输出读入一个数组，然后对其进行迭代:

An alternative that reads all the jq output into an array and then iterates it:

readarray -t lines < <(jq ".[] | .name, .nested_name.name" <<<"$json")
for (( i = 0; i < ${#lines[@]}; i += 2 )); do
    foo=${lines[i]}
    bar=${lines[i+1]}
    printf "foo=%s\nbar=%s\n" "$foo" "$bar"
done

这篇关于将多个 jq 值通过管道传输到“while read -r"；环形的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！