在Linux Bash中从cURL获取JSON值

Question

我想GET从服务器获取一些json数据.我这样做使用:

UPDATE=$(curl -i -H "Accept: application/json" -H "Content-Type: application/json" --cookie "${COOKIE_NAME}" "${1}/update/${DEVICE_NAME}");

在此之前,服务器已通过身份验证.该${1}是服务器领域,${DEVICE_NAME}是请求更新的设备的名称.

这将返回一个JSON,如下所示:

[{ "_id": "54ff35887d8ef574029b9166", "用户": "54fe4313883bcec2c0ac0d64", "__ V":0, "创建": "2015-03-10T18:18:48.023Z", "状态": "可用的"," pbo_udid":"lemaker","installation_script":"","description":"打印hello world to console","package_name":"helloworld_1.0-1.deb","name":"Hello World V1"} ]

我现在要做两件事:

1. 确保返回数据(如果没有可用的更新,则服务器返回 []
2. 例如,提取数据 package_name

我如何在Linux bash脚本中执行这些操作？

Answer 1

使用jq或jsawk更容易和可靠地完成:

content=$(curl ...)
package_name=$(jq -r '.package_name' <<<"$content")

Answer 2

假设没有嵌套数组：

cat <<EOF | json_reformat | \
    sed -rne '/:/s@^\s+"(\w+)":\s+"([^"]+)",?@json_\1="\2"@gp'
[{"_id":"54ff35887d8ef574029b9166","user":"54fe4313883bcec2c0ac0d64","__v":0,"created":"2015-03-10T18:18:48.023Z","status":"available","pbo_udid":"lemaker","installation_script":"","description":"Prints hello world to console","package_name":"helloworld_1.0-1.deb","name":"Hello World V1"}]
EOF

回报

json__id="54ff35887d8ef574029b9166"
json_user="54fe4313883bcec2c0ac0d64"
json_created="2015-03-10T18:18:48.023Z"
json_status="available"
json_pbo_udid="lemaker"
json_description="Prints hello world to console"
json_package_name="helloworld_1.0-1.deb"
json_name="Hello World V1"

你需要json_reformat让它发挥作用。

编辑：没有json_reformat：

cat <<EOF | \
    sed -re 's@(\[|\]|\{|\})@@g' -e 's/,/\n/g' | \
    sed -re 's@"(\w+)":\s*"?([^"]*)"?@json_\1="\2"@g'
[{"_id":"54ff35887d8ef574029b9166","user":"54fe4313883bcec2c0ac0d64","__v":0,"created":"2015-03-10T18:18:48.023Z","status":"available","pbo_udid":"lemaker","installation_script":"","description":"Prints hello world to console","package_name":"helloworld_1.0-1.deb","name":"Hello World V1"}]
EOF

它返回（请注意无论如何重新格式化的版本号）：

json__id="54ff35887d8ef574029b9166"
json_user="54fe4313883bcec2c0ac0d64"
json___v="0"
json_created="2015-03-10T18:18:48.023Z"
json_status="available"
json_pbo_udid="lemaker"
json_installation_script=""
json_description="Prints hello world to console"
json_package_name="helloworld_1.0-1.deb"
json_name="Hello World V1"

您现在可以尝试使用标准输入解析此文本eval或从标准输入获取它。