jq类似一个awk或grep一样的神器，可以方便地在命令行操作json

一、安装

官网：https://stedolan.github.io/jq/download/

基本就是brew install、apt install、yum install之类的，很简单

二、常用操作

1.格式化json

直接请求

格式如下，不易读

➜ ~ curl -s http://t.weather.sojson.com/api/weather/city/101310215

{"message":"success感谢又拍云(upyun.com)提供CDN赞助","status":200,"date":"20191025","time":"2019-10-25 11:17:41","cityInfo":{"city":"万宁市","citykey":"101310215","parent":"海南","updateTime":"09:59"},"data":{"shidu":"92%","pm25":20.0,"pm10":49.0,"quality":"优","wendu":"25","ganmao":"各类人群可自由活动","forecast":[{"date":"25","high":"高温 29℃","low":"低温 23℃","ymd":"2019-10-25","week":"星期五","sunrise":"06:35","sunset":"18:10","aqi":44,"fx":"无持续风向","fl":"<3级","type":"中雨","notice":"记得随身携带雨伞哦"},{"date":"26","high":"高温 29℃","low":"低温 23℃","ymd":"2019-10-26","week":"星期六","sunrise":"06:35","sunset":"18:09","aqi":31,"fx":"无持续风向","fl":"<3级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"27","high":"高温 29℃","low":"低温 23℃","ymd":"2019-10-27","week":"星期日","sunrise":"06:36","sunset":"18:09","aqi":28,"fx":"无持续风向","fl":"<3级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"28","high":"高温 30℃","low":"低温 22℃","ymd":"2019-10-28","week":"星期一","sunrise":"06:36","sunset":"18:08","aqi":34,"fx":"东北风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"29","high":"高温 27℃","low":"低温 22℃","ymd":"2019-10-29","week":"星期二","sunrise":"06:36","sunset":"18:07","aqi":35,"fx":"东北风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"30","high":"高温 27℃","low":"低温 22℃","ymd":"2019-10-30","week":"星期三","sunrise":"06:37","sunset":"18:07","aqi":32,"fx":"无持续风向","fl":"<3级","type":"中雨","notice":"记得随身携带雨伞哦"},{"date":"31","high":"高温 29℃","low":"低温 22℃","ymd":"2019-10-31","week":"星期四","sunrise":"06:37","sunset":"18:06","fx":"东北风","fl":"3-4级","type":"中雨","notice":"记得随身携带雨伞哦"},{"date":"01","high":"高温 25℃","low":"低温 24℃","ymd":"2019-11-01","week":"星期五","sunrise":"06:38","sunset":"18:06","fx":"东北风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"02","high":"高温 25℃","low":"低温 24℃","ymd":"2019-11-02","week":"星期六","sunrise":"06:38","sunset":"18:05","fx":"东北风","fl":"4-5级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"03","high":"高温 26℃","low":"低温 24℃","ymd":"2019-11-03","week":"星期日","sunrise":"06:38","sunset":"18:05","fx":"东风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"04","high":"高温 25℃","low":"低温 24℃","ymd":"2019-11-04","week":"星期一","sunrise":"06:39","sunset":"18:04","fx":"东北风","fl":"<3级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"05","high":"高温 28℃","low":"低温 24℃","ymd":"2019-11-05","week":"星期二","sunrise":"06:39","sunset":"18:04","fx":"东南风","fl":"<3级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"06","high":"高温 25℃","low":"低温 21℃","ymd":"2019-11-06","week":"星期三","sunrise":"06:40","sunset":"18:04","fx":"东北风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"07","high":"高温 23℃","low":"低温 22℃","ymd":"2019-11-07","week":"星期四","sunrise":"06:40","sunset":"18:03","fx":"东北风","fl":"3-4级","type":"小雨","notice":"雨虽小，注意保暖别感冒"},{"date":"08","high":"高温 25℃","low":"低温 22℃","ymd":"2019-11-08","week":"星期五","sunrise":"06:41","sunset":"18:03","fx":"北风","fl":"3-4级","type":"多云","notice":"阴晴之间，谨防紫外线侵扰"}],"yesterday":{"date":"24","high":"高温 29℃","low":"低温 23℃","ymd":"2019-10-24","week":"星期四","sunrise":"06:34","sunset":"18:10","aqi":27,"fx":"无持续风向","fl":"<3级","type":"多云","notice":"阴晴之间，谨防紫外线侵扰"}}}

使用jq格式化，如下

curl -s http://t.weather.sojson.com/api/weather/city/101310215 | jq

{

"message": "success感谢又拍云(upyun.com)提供CDN赞助",

"status": 200,

"date": "20191025",

"time": "2019-10-25 10:27:28",

"cityInfo": {

"city": "万宁市",

"citykey": "101310215",

"parent": "海南",

"updateTime": "09:59"

},

"data": {

"shidu": "92%",

"pm25": 20,

"pm10": 49,

"quality": "优",

"wendu": "25",

"ganmao": "各类人群可自由活动",

"forecast": [

{

"date": "25",

"high": "高温 29℃",

"low": "低温 23℃",

"ymd": "2019-10-25",

"week": "星期五",

"sunrise": "06:35",

"sunset": "18:10",

"aqi": 44,

"fx": "无持续风向",

"fl": "<3级",

"type": "中雨",

"notice": "记得随身携带雨伞哦"

},...

已经格式化过

2.取指定字段的值

直接输入字段，使用.嵌套访问，如要获取昨天的信息

curl -s http://t.weather.sojson.com/api/weather/city/101310215 | jq .data.yesterday

{

"date": "24",

"high": "高温 29℃",

"low": "低温 23℃",

"ymd": "2019-10-24",

"week": "星期四",

"sunrise": "06:34",

"sunset": "18:10",

"aqi": 27,

"fx": "无持续风向",

"fl": "<3级",

"type": "多云",

"notice": "阴晴之间，谨防紫外线侵扰"

}

3.过滤指定字段

使用一个json指定所有字段，如{date, high}，获取昨天的最高温度如下

curl -s http://t.weather.sojson.com/api/weather/city/101310215 | jq .data.yesterday|jq "{date,high}"

{

"date": "24",

"high": "高温 29℃"

}

4.获取多个字段的值

使用逗号获取多个

curl -s http://t.weather.sojson.com/api/weather/city/101310215 | jq .data.yesterday|jq ".date, .high"

"24"

"高温 29℃"

5.筛选数组

直接指定数组的索引即可

curl -s http://t.weather.sojson.com/api/weather/city/101310215 |jq ".data.forecast"|jq ".[0,9]"

{

"date": "25",

"high": "高温 29℃",

"low": "低温 23℃",

"ymd": "2019-10-25",

"week": "星期五",

"sunrise": "06:35",

"sunset": "18:10",

"aqi": 44,

"fx": "无持续风向",

"fl": "<3级",

"type": "中雨",

"notice": "记得随身携带雨伞哦"

}

{

"date": "03",

"high": "高温 26℃",

"low": "低温 24℃",

"ymd": "2019-11-03",

"week": "星期日",

"sunrise": "06:38",

"sunset": "18:05",

"fx": "东风",

"fl": "3-4级",

"type": "小雨",

"notice": "雨虽小，注意保暖别感冒"

}