Json使用shell脚本进行对象分析

Question

我正在尝试使用shell脚本解析下面的json对象：

country.json

{
"countries": [
{"country":"India","city":["India1","India2","India3"]},
{"country":"USA","city":["USA1","USA2","USA3"]}

]
}

并且我的期望输出应该是：

country:India, city:India1
country:India, city:India2
country:India, city:India3
country:USA, city:USA1
country:USA, city:USA2
country:USA, city:USA3 

我在shell脚本中使用jq来迭代上面的json，如下所示：

for k in $(jq '.countries | keys | .[]' country.json); do
countryObj=$(jq -r ".countries[$k]" country.json);
countryValue=$(jq -r '.country' <<< "$countryObj");
city_array=$(jq -r '.city' <<< "$countryObj");
echo $city_array
done 

由此，我可以获得city_array，即["India1","India2","India3"]和["USA1","USA2","USA3"]，但我无法获得上述所需的输出

Answer 1

这完全可以在jq中完成。

jq -r '
.countries |
map(
.country as $country |
.city | map("country: ( $country ), city: ( . )n") | add
) |
join("n")
'

提供：

country: India, city: India1
country: India, city: India2
country: India, city: India3
country: USA, city: USA1
country: USA, city: USA2
country: USA, city: USA3

jqplay

---

如果你不需要空白行，它会简单得多。

jq -r '
.countries[] |
.country as $country |
.city[] |
"country: ( $country ), city: ( . )"
'

jqplay

Answer 2

添加一个循环，为每个$countryObj迭代$city_array中的每个city，然后逐行迭代echo您想要的输出。

for k in $(jq '.countries | keys | .[]' country.json); do
countryObj=$(jq -r ".countries[$k]" country.json);
countryValue=$(jq -r '.country' <<< "$countryObj");
city_array=$(jq -r '.city' <<< "$countryObj");

for city in $city_array; do
echo "country:$countryValue, city:$city"
done
echo "" # Blank line between each country
done