jq可以對json數據進行分片、過濾、映射和轉換
安裝
#CentOS
yum install jq
#MacOS
brew install jq
提取信息
cat json.txt
[{"genre":"deep house"}, {"genre": "progressive house"}, {"genre": "dubstep"}]
- 格式化展示原文
cat json.txt | jq '.'
[
{
"genre": "deep house"
},
{
"genre": "progressive house"
},
{
"genre": "dubstep"
}
]
- 輸出數組中的元素,可以使用[index]
cat json.txt | jq '.[0]'
{
"genre": "deep house"
}
- 輸出對象的一個字段
jq '.[0].genre' json.txt
"deep house"
數據轉換
- 過濾字段
cat json.txt| jq -c '[.[] | {"name", "age"}]'
[{"name":"tenmao","age":100},{"name":"tencent","age":null}]
- 根據KV的值過濾值
cat json.txt| jq -c 'map(select(.name == "tenmao"))'
[{"genre":"deep house","name":"tenmao","age":100}]
- 增加字段
# 使用map: 映射, 其中.號表示原文, + 表示merge信息
# if then else end是邏輯語句
cat json.txt| jq -c 'map(if .name == "tenmao" then . + {hobby: "baskball"} else . end)'
[{"genre":"deep house","name":"tenmao","age":100,"hobby":"baskball"},{"genre":"progressive house","name":"tencent"}]