使用 jq 将文件内容转换为 json 字符串在命令替换中不起作用

Question

这是按预期工作的：

$ cat /etc/tfe-config/sources/fluent-bit.conf.tpl | jq -R -s
$ "[OUTPUT]\n    Name               cloudwatch_logs\n    Match              *\n    region             eu-central-1\n    log_group_name     TFE-LogForwarding\n    log_stream_name    TFE-AllLogs"

但是，分配给变量不起作用：

$ MY_VARIABLE=$(cat /etc/tfe-config/sources/fluent-bit.conf.tpl | jq -R -s)
$ echo $MY_VARIABLE 
jq - commandline JSON processor [version 1.5]
Usage: jq [options] <jq filter> [file...]

        jq is a tool for processing JSON inputs, applying the
        given filter to its JSON text inputs and producing the
        filter's results as JSON on standard output.
        The simplest filter is ., which is the identity filter,
        copying jq's input to its output unmodified (except for
        formatting).
        For more advanced filters see the jq(1) manpage ("man jq")
        and/or https://stedolan.github.io/jq

        Some of the options include:
         -c             compact instead of pretty-printed output;
       .... trimmed

我在带有最新 Amazon Linux 2 映像的 AWS EC2 机器上。

这是怎么回事？

文件如下所示：

[OUTPUT]
    Name               cloudwatch_logs
    Match              *
    region             eu-central-1
    log_group_name     TFE-LogForwarding
    log_stream_name    TFE-AllLogs

Answer 1

两件事：

• 您必须为 jq 指定一个过滤器 - 只需 . 即可获取整个输入
• 一旦在带有空格的变量中，您必须引用该字符串，否则当您打印它时它会以不同的方式显示

var=$(cat /etc/tfe-config/sources/fluent-bit.conf.tpl | jq -R -s '.')
echo "$var" 

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