在 Linux Bash 中从 cURL 获取 JSON 值

Getting JSON value from cURL in Linux Bash

提问by Kousha

I want to GETsome json data from a server. I do this using:

我想要GET一些来自服务器的 json 数据。我这样做使用：

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

Before this, the server is authenticated. The ${1}is the server domain, ${DEVICE_NAME}is the name of the device requesting the update.

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。

This returns a JSON as follows:

这将返回一个 JSON，如下所示：

[{"_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"}]

[{"_id":"54ff35887d8ef574029b9166","user":"54fe4313883bcec2c0ac0d64","__v":0,"created":"2015-03-10T18:18:48.023","stat","Z" pbo_udid":"lemaker","installation_script":"","description":"将hello world打印到控制台","package_name":"helloworld_1.0-1.deb","name":"Hello World V1"} ]

I want to now do 2 things:

我现在想做两件事：

1. Make sure data is returned (if no update is available, the server returns []
2. Extract data, for instance package_name

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

How do I do these in Linux bash script?

我如何在 Linux bash 脚本中执行这些操作？

采纳答案by Kousha

Assuming there's no nested array:

假设没有嵌套数组：

cat <<EOF | json_reformat | \
    sed -rne '/:/s@^\s+"(\w+)":\s+"([^"]+)",?@json_=""@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

returns

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"

You need json_reformatfor this to work.

你需要json_reformat这个才能工作。

EDIT: without json_reformat:

编辑：没有json_reformat：

cat <<EOF | \
    sed -re 's@(\[|\]|\{|\})@@g' -e 's/,/\n/g' | \
    sed -re 's@"(\w+)":\s*"?([^"]*)"?@json_=""@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

It returns (note the version number that is reformatted anyway):

它返回（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"

You can now try parsing this text using evalor source it from stdin.

您现在可以尝试使用evalstdin 或从 stdin 中解析此文本。

回答by Charles Duffy

Much more easily and reliably done using jqor jsawk:

使用jq或jsawk更容易、更可靠地完成：

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