[svc]jq神器使用

jq神器

处理json数据
支持过滤某字段
支持数学运算(对字段处理)

• 安装

yum install -y jq

• 使用

参考:
http://blog.just4fun.site/command-tool-jq.html
https://www.ibm.com/developerworks/cn/linux/1612_chengg_jq/index.html

在线jq表达式匹配:
https://jqplay.org/

• 教程

https://stedolan.github.io/jq/tutorial/

过滤超过18岁的

[{
    "name" : "maotai",
    "age" : 18,
    "gender" : "male"
},

{
    "name" : "maotai",
    "age" : 19,
    "gender" : "male"
},
{
    "name" : "maotai",
    "age" : 20,
    "gender" : "male"
}]

cat t.tt | jq -r 'map(select(.age>18))'

json数据的第一项

cat t.tt | jq '.[0]'

• 示例json数据
  

{
"sha": "79ece359819cdd7d033d272af9758ae22204c2ef",
"commit": {
  "author": {
    "name": "William Langford",
    "email": "wlangfor@gmail.com",
    "date": "2017-12-05T01:10:56Z"
  },
  "committer": {
    "name": "William Langford",
    "email": "wlangfor@gmail.com",
    "date": "2017-12-05T01:10:56Z"
  },
  "message": "Fix hang for slurped inputs with trailing newline",
  "tree": {
    "sha": "d3b481f3448ecd50bf4aa109fd6564dd923afede",
    "url": "https://api.github.com/repos/stedolan/jq/git/trees/d3b481f3448ecd50bf4aa109fd6564dd923afede"
  },
  "url": "https://api.github.com/repos/stedolan/jq/git/commits/79ece359819cdd7d033d272af9758ae22204c2ef",
  "comment_count": 0,
  "verification": {
    "verified": false,
    "reason": "unsigned",
    "signature": null,
    "payload": null
  }
},
"url": "https://api.github.com/repos/stedolan/jq/commits/79ece359819cdd7d033d272af9758ae22204c2ef",
"html_url": "https://github.com/stedolan/jq/commit/79ece359819cdd7d033d272af9758ae22204c2ef",
"comments_url": "https://api.github.com/repos/stedolan/jq/commits/79ece359819cdd7d033d272af9758ae22204c2ef/comments",
"author": {
  "login": "wtlangford",
  "id": 3422295,
  "avatar_url": "https://avatars2.githubusercontent.com/u/3422295?v=4",
  "gravatar_id": "",
  "url": "https://api.github.com/users/wtlangford",
  "html_url": "https://github.com/wtlangford",
  "followers_url": "https://api.github.com/users/wtlangford/followers",
  "following_url": "https://api.github.com/users/wtlangford/following{/other_user}",
  "gists_url": "https://api.github.com/users/wtlangford/gists{/gist_id}",
  "starred_url": "https://api.github.com/users/wtlangford/starred{/owner}{/repo}",
  "subscriptions_url": "https://api.github.com/users/wtlangford/subscriptions",
  "organizations_url": "https://api.github.com/users/wtlangford/orgs",
  "repos_url": "https://api.github.com/users/wtlangford/repos",
  "events_url": "https://api.github.com/users/wtlangford/events{/privacy}",
  "received_events_url": "https://api.github.com/users/wtlangford/received_events",
  "type": "User",
  "site_admin": false
},
"committer": {
  "login": "wtlangford",
  "id": 3422295,
  "avatar_url": "https://avatars2.githubusercontent.com/u/3422295?v=4",
  "gravatar_id": "",
  "url": "https://api.github.com/users/wtlangford",
  "html_url": "https://github.com/wtlangford",
  "followers_url": "https://api.github.com/users/wtlangford/followers",
  "following_url": "https://api.github.com/users/wtlangford/following{/other_user}",
  "gists_url": "https://api.github.com/users/wtlangford/gists{/gist_id}",
  "starred_url": "https://api.github.com/users/wtlangford/starred{/owner}{/repo}",
  "subscriptions_url": "https://api.github.com/users/wtlangford/subscriptions",
  "organizations_url": "https://api.github.com/users/wtlangford/orgs",
  "repos_url": "https://api.github.com/users/wtlangford/repos",
  "events_url": "https://api.github.com/users/wtlangford/events{/privacy}",
  "received_events_url": "https://api.github.com/users/wtlangford/received_events",
  "type": "User",
  "site_admin": false
},
"parents": [
  {
    "sha": "f06deb828a318536b85d68280d429c3a70b21259",
    "url": "https://api.github.com/repos/stedolan/jq/commits/f06deb828a318536b85d68280d429c3a70b21259",
    "html_url": "https://github.com/stedolan/jq/commit/f06deb828a318536b85d68280d429c3a70b21259"
  }
]
}

• 格式化json

curl 'https://api.github.com/repos/stedolan/jq/commits?per_page=5' | jq '.'

• 输出数组的第一项

curl 'https://api.github.com/repos/stedolan/jq/commits?per_page=5' | jq '.[0]'

• 按照某些字段重组json

jq '.[0] | {message: .commit.message, name: .commit.committer.name}'

• 按照某些字段重组json(抽出所有项)

jq '.[] | {message: .commit.message, name: .commit.committer.name}'

• 按照某些字段重组json(抽出所有项)(结果弄成一个[])

jq '[.[] | {message: .commit.message, name: .commit.committer.name}]'

• 返回的字段值为数组

jq '[.[] | {message: .commit.message, name: .commit.committer.name, parents: [.parents[].html_url]}]'

$ curl 'https://api.github.com/repos/stedolan/jq/commits?per_page=5' |jq '[.[0] | {message: .commit.message, name: .commit.committer.name, parents: [.parents[].html_url]}]'
[
  {
    "message": "Fix hang for slurped inputs with trailing newline",
    "name": "William Langford",
    "parents": [
      "https://github.com/stedolan/jq/commit/f06deb828a318536b85d68280d429c3a70b21259"
    ]
  }
]