我的用例可能与这篇原始文章所要求的完全相同，也可能不完全相同，但它肯定是相似的。

我需要拉一些YAML作为bash变量。YAML的深度永远不会超过一层。

YAML看起来是这样的:

KEY:                value
ANOTHER_KEY:        another_value
OH_MY_SO_MANY_KEYS: yet_another_value
LAST_KEY:           last_value

输出如下:

KEY="value"
ANOTHER_KEY="another_value"
OH_MY_SO_MANY_KEYS="yet_another_value"
LAST_KEY="last_value"

我用这一行实现了输出:

sed -e 's/:[^:\/\/]/="/g;s/$/"/g;s/ *=/=/g' file.yaml > file.sh

s/:[^:\/\/]/="/g查找:并将其替换为="，同时忽略://(对于url) S /$/"/g将"附加到每一行的末尾 S / *=/=/g删除=前面的所有空格

把我的答案从如何在bash中将json响应转换为yaml，因为这似乎是关于从命令行处理yaml文本解析的权威帖子。

我想添加一些关于yq YAML实现的细节。由于这个YAML解析器有两种实现，名称都是yq，如果不查看实现的DSL，就很难区分使用的是哪一种。有两个可用的实现

kislyuk/yq——更常被提及的版本，它是jq的包装器，用Python编写，使用PyYAML库进行YAML解析 mikefarah/yq -一个Go实现，使用Go -yaml v3解析器，有自己的动态DSL。

几乎所有主要发行版都可以通过标准安装包管理器进行安装

kislyuk/yq -安装说明 mikefarah/yq -安装说明

这两个版本都有一些优点和缺点，但有一些有效的点需要强调(从他们的回购指令中采用)

kislyuk - yq

Since the DSL is the adopted completely from jq, for users familiar with the latter, the parsing and manipulation becomes quite straightforward Supports mode to preserve YAML tags and styles, but loses comments during the conversion. Since jq doesn't preserve comments, during the round-trip conversion, the comments are lost. As part of the package, XML support is built in. An executable, xq, which transcodes XML to JSON using xmltodict and pipes it to jq, on which you can apply the same DSL to perform CRUD operations on the objects and round-trip the output back to XML. Supports in-place edit mode with -i flag (similar to sed -i)

迈克法拉/YQ

Prone to frequent changes in DSL, migration from 2.x - 3.x Rich support for anchors, styles and tags. But lookout for bugs once in a while A relatively simple Path expression syntax to navigate and match yaml nodes Supports YAML->JSON, JSON->YAML formatting and pretty printing YAML (with comments) Supports in-place edit mode with -i flag (similar to sed -i) Supports coloring the output YAML with -C flag (not applicable for JSON output) and indentation of the sub elements (default at 2 spaces) Supports Shell completion for most shells - Bash, zsh (because of powerful support from spf13/cobra used to generate CLI flags)

我对以下两个版本的YAML的看法(在其他答案中也有引用)

root_key1: this is value one
root_key2: "this is value two"

drink:
  state: liquid
  coffee:
    best_served: hot
    colour: brown
  orange_juice:
    best_served: cold
    colour: orange

food:
  state: solid
  apple_pie:
    best_served: warm

root_key_3: this is value three

对这两个实现执行的各种操作(一些常用操作)

修改根节点值—修改“root_key2”的值 修改数组内容，增加值-为coffee添加属性 修改数组内容，删除value - Delete属性从orange_juice 打印带有路径的键/值对—用于food下的所有项目

使用kislyuk / yq

Yq -y '。Root_key2 |= "this is a new value 你，你，喝。咖啡+={时间:"always"}' yaml Yq -y 'del(.drink.orange_juice.colour)' yaml yq - r的.food |路径(标量)美元p | (($ p |加入(“。”)),(getpath ($ p) | tojson)] | @tsv的yaml

这很简单。你所需要做的就是用-y标志将jq JSON输出转码回YAML。

用mikefarah - yq

Yq w yaml root_key2 "这是一个新值" Yq w yaml喝。咖啡。时间“总是” Yq d yaml饮料。橙汁。颜色 yq r yaml——printMode pv "food.**"

截至2020年12月21日，yq v4是测试版，支持许多强大的路径表达式，并支持类似于使用jq的DSL。阅读过渡说明-从V3升级

我已经用python编写了shyaml，用于从shell命令行查询YAML。

概述:

$ pip install shyaml      ## installation

示例的YAML文件(具有复杂的功能):

$ cat <<EOF > test.yaml
name: "MyName !!"
subvalue:
    how-much: 1.1
    things:
        - first
        - second
        - third
    other-things: [a, b, c]
    maintainer: "Valentin Lab"
    description: |
        Multiline description:
        Line 1
        Line 2
EOF

基本的查询:

$ cat test.yaml | shyaml get-value subvalue.maintainer
Valentin Lab

更复杂的循环查询复杂的值:

$ cat test.yaml | shyaml values-0 | \
  while read -r -d $'\0' value; do
      echo "RECEIVED: '$value'"
  done
RECEIVED: '1.1'
RECEIVED: '- first
- second
- third'
RECEIVED: '2'
RECEIVED: 'Valentin Lab'
RECEIVED: 'Multiline description:
Line 1
Line 2'

以下几个要点:

all YAML types and syntax oddities are correctly handled, as multiline, quoted strings, inline sequences... \0 padded output is available for solid multiline entry manipulation. simple dotted notation to select sub-values (ie: subvalue.maintainer is a valid key). access by index is provided to sequences (ie: subvalue.things.-1 is the last element of the subvalue.things sequence.) access to all sequence/structs elements in one go for use in bash loops. you can output whole subpart of a YAML file as ... YAML, which blend well for further manipulations with shyaml.

更多的示例和文档可以在shyaml github页面或shyaml PyPI页面上找到。

如果你需要一个单一的值，你可以使用一个工具将你的YAML文档转换为JSON并提供给jq，例如yq。

sample.yaml的内容:

---
bob:
  item1:
    cats: bananas
  item2:
    cats: apples
  thing:
    cats: oranges

例子:

$ yq -r '.bob["thing"]["cats"]' sample.yaml 
oranges

我知道我的回答很具体，但是如果已经安装了PHP和Symfony，那么使用Symfony的YAML解析器会非常方便。

例如:

php -r "require '$SYMFONY_ROOT_PATH/vendor/autoload.php'; \
    var_dump(\Symfony\Component\Yaml\Yaml::parse(file_get_contents('$YAML_FILE_PATH')));"

这里我只是简单地使用var_dump来输出解析后的数组，当然你还可以做更多…：）

现在做这件事的一个快速方法(以前的方法对我没用):

sudo wget https://github.com/mikefarah/yq/releases/download/v4.4.1/yq_linux_amd64 -O /usr/bin/yq &&\
sudo chmod +x /usr/bin/yq

示例asd.yaml:

a_list:
  - key1: value1
    key2: value2
    key3: value3

解析:根

user@vm:~$ yq e '.' asd.yaml                                                                                                         
a_list:
  - key1: value1
    key2: value2
    key3: value3

解析key3:

user@vm:~$ yq e '.a_list[0].key3' asd.yaml                                                                                             
value3