yq命令安装及基础使用

安装

yq命令可以直接从Git的发布页面中下载与操作系统内核一致的版本的bin文件使用，详见此链接地址。

例如在x86架构下，直接下载使用即可。

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

简单使用

从yaml文件读取参数。

yq '.a.b[0].c' file.yaml

更新参数值。

yq -i '.a.b[0].c = "cool"' file.yaml

使用环境变量更新参数值。

NAME=mike yq -i '.a.b[0].c = strenv(NAME)' file.yaml

一次更新多个参数值。

yq -i '
  .a.b[0].c = "cool" |
  .x.y.z = "foobar" |
  .person.name = strenv(NAME)
' file.yaml

删除键值。

yq -i 'del(.b)' file.yaml

环境变量操作

直接写入参数值。

myenv="cat meow" yq --null-input '.a = env(myenv)'

输出信息。

a: cat meow

以字符串写入参数值。

myenv="true" yq --null-input '.a = strenv(myenv)'

输出信息。

a: "true"

JSON处理

JSON转换为YAML。

yq -p=json sample.json

输出示例。

cat: meow

YAML转换为JSON。

yq -o=json '.' sample.yml

输出示例。

{
  "cat": "meow"
}

JSON转CSV

{
    "code": "0",
    "msg": "success",
    "data": {
        "total": 406,
        "pageNo": 1,
        "pageSize": 500,
        "list": [
            {
                "cameraIndexCode": "dde45299daad4c2fb6c44c2f3a421595",
                "cameraName": "camera1",
                "cameraType": 0,
                "cameraTypeName": "枪机"
            },
            {
                "cameraIndexCode": "7c6ad868131b4a60b77dfd894f2e5d1c",
                "cameraName": "camera2",
                "cameraType": 0,
                "cameraTypeName": "枪机"
            }
        ]
    }
}

yq '.data.list[] |[.cameraIndexCode,.cameraName] | @csv' camera.json > camera.csv

JSON提取字段

{
  "a":"1",
  "b":"2",
  "c":["3","4"]
}

yq '. |= pick( ["a","b"] )' sample.json
yq -I0 '. |= pick(["a","b","c"]) | .c = .c[0]' sample.json

JSON数组排序

echo '{"data":[{"id":"2"},{"id":"1"}]}' | yq '.data |= sort_by(.id)'

{"data": [{"id": "1"}, {"id": "2"}]}

Properties文件处理

示例文件：

# block comments come through
# comments on values appear
person.name = Mike Wazowski

# comments on array values appear
person.pets.0 = cat
person.pets.1.nested.0 = list entry
person.food.0 = pizza

进行修改操作：

yq -p=props -o=props '.person.pets.0 = "dog"' sample.properties

输出信息：

# block comments come through
# comments on values appear
person.name = Mike Wazowski

# comments on array values appear
person.pets.0 = dog
person.pets.1.nested.0 = list entry
person.food.0 = pizza

其它语法

详见官方文档。

Usage:
  yq [flags]
  yq [command]

Examples:

# yq defaults to 'eval' command if no command is specified. See "yq eval --help" for more examples.
yq '.stuff' < myfile.yml # outputs the data at the "stuff" node from "myfile.yml"

yq -i '.stuff = "foo"' myfile.yml # update myfile.yml in place


Available Commands:
  completion       Generate the autocompletion script for the specified shell
  eval             (default) Apply the expression to each document in each yaml file in sequence
  eval-all         Loads _all_ yaml documents of _all_ yaml files and runs expression once
  help             Help about any command

Flags:
  -C, --colors                        force print with colors
  -e, --exit-status                   set exit status if there are no matches or null or false is returned
  -f, --front-matter string           (extract|process) first input as yaml front-matter. Extract will pull out the yaml content, process will run the expression against the yaml content, leaving the remaining data intact
      --header-preprocess             Slurp any header comments and separators before processing expression. (default true)
  -h, --help                          help for yq
  -I, --indent int                    sets indent level for output (default 2)
  -i, --inplace                       update the file in place of first file given.
  -p, --input-format string           [yaml|y|xml|x] parse format for input. Note that json is a subset of yaml. (default "yaml")
  -M, --no-colors                     force print with no colors
  -N, --no-doc                        Don't print document separators (---)
  -n, --null-input                    Don't read input, simply evaluate the expression given. Useful for creating docs from scratch.
  -o, --output-format string          [yaml|y|json|j|props|p|xml|x] output format type. (default "yaml")
  -P, --prettyPrint                   pretty print, shorthand for '... style = ""'
  -s, --split-exp string              print each result (or doc) into a file named (exp). [exp] argument must return a string. You can use $index in the expression as the result counter.
      --unwrapScalar                  unwrap scalar, print the value with no quotes, colors or comments (default true)
  -v, --verbose                       verbose mode
  -V, --version                       Print version information and quit
      --xml-attribute-prefix string   prefix for xml attributes (default "+")
      --xml-content-name string       name for xml content (if no attribute name is present). (default "+content")

Use "yq [command] --help" for more information about a command.