LinkedIn does not return all possible member profile fields that are
available to you by default. There is a limited selection of
additional member fields that are also available to you which may be
relevant to your application. Refer to the Basic Profile Fields page
for a complete list of the basic member profile fields.
The following example demonstrates how to customize your API call to
request specific member profile fields that you wish to be returned
during the Sign In with LinkedIn workflow:
GET
https://api.linkedin.com/v1/people/~:(id,num-connections,picture-url)?format=json
sample api response:
{
"id": "1R2RtA",
"numConnections": 42,
"pictureUrl": "https://media.licdn.com/mpr/mprx/…"
}
https://developer.linkedin.com/docs/signin-with-linkedin