OpenWRT使用shell解析json
使用shell解析json依赖于/usr/share/libubox/jshn.sh文件
常用的获取信息的接口有
- json_load
- json_select
- json_get_var
常用的构建json的接口有
- json_init
- json_add_object
- json_add_string
- json_add_int
- json_add_boolean
- json_add_array
- json_dump
获取预设的LAN，WAN的接口名称
board.json文件为
root@Localhost:/www# cat /etc/board.json
{
"switch": {
"switch0": {
"enable": true,
"reset": true,
"ports": [
{
"num": 5,
"device": "eth0",
"need_tag": false,
"want_untag": false
},
{
"num": 1,
"role": "lan",
"index": 1
},
{
"num": 2,
"role": "lan",
"index": 2
},
{
"num": 3,
"role": "lan",
"index": 3
},
{
"num": 4,
"role": "lan",
"index": 4
},
{
"num": 0,
"role": "wan"
}
],
"roles": [
{
"role": "lan",
"ports": "1 2 3 4 5t",
"device": "eth0.1"
},
{
"role": "wan",
"ports": "0 5t",
"device": "eth0.2"
}
]
}
},
"network": {
"lan": {
"ifname": "eth0.1",
"protocol": "static"
},
"wan": {
"ifname": "eth0.2",
"protocol": "dhcp"
}
}
}
解析脚本如下
#！/bin/sh
. /lib/functions.sh
. /usr/share/libubox/jshn.sh
json_load “$(cat /etc/board.json)” 加载board描述文件
json_select network 切换network对象
json_select lan 切换到lan对象
json_get_var name ifname 从lan对象中获取ifname字段值保存在name中
echo “lan ifname is $name”
json_select .. 退回到上级对象
json_select wan 切换到wan对象
json_get_var name ifname 从wan对象中获取ifname字段值保存在name中
echo “wan ifname is $name”
脚本运行完毕后打印出
lan ifname is eth0.1
wan ifname is eth0.2
构建json
#!/bin.sh
. /usr/share/libubox/jshn.sh
json_init 初始化环境
json_add_object "test" 增加test对象
json_add_string "name" "test" 在test对象中增加name字段，值为test
json_add_int "id" 10086 在test对象中增加id字段，值为10086
json_add_boolean "online" 1 在test对象中增加online字段，值为true
json_add_double "money" 100.86 在test对象中增加money字段，值为100.86
echo "cur = $JSON_CUR" 打印当前对象名称
json_select .. 切换到上一层
json_add_array "array" 增加一个array数组
json_add_string "" "v1" 增加v1
json_add_string "" "v2" 增加v2
echo "cur = $JSON_CUR"
json_get_keys keys 遍历数组将其存放在keys
for k in $keys; do 遍历keys进行打印
json_get_var v "$k"
echo "$k -- $v"
done
echo "name is $name"
json_select .. 切换到上一层
echo "cur = $JSON_CUR"
json_add_int "gggg" 88888
json_add_string "gggg" "sdfsdfsdf"
json_dump
最终结果为：
cur = J_T1
cur = J_A2
1 -- v1
2 -- v2
name is
cur = J_V
{ "test": {
"name": "test",
"id": 10086,
"online": true,
"money": 100.86
},
"array": [ "v1", "v2" ],
"gggg": "sdfsdfsdf"
}
加粗字体为对象的dump，我们看到gggg为int的8888并没有打印出来，也就是说在一个对象中字段名称不能重复
JSON和UCI
config timeserver 'ntp'
option enabled '0'
option enable_server '0'
脚本如下
#!/bin/sh
. /usr/share/libubox/jshn.sh
. /lib/functions.sh
json_init
config_load system
config_get __enable "ntp" enable 获取ntp段中enable的值存放在__enable中
json_add_boolean enable $__enable
json_dump
运行结果
{ "enable": false }
