Place Details using Place API library in node.js

I'm trying to get Place Details in a node.js app. To simplified requests, I decided to use a node module called googlemaps.

Here's a sample code to get Place Details with it :

var googlemaps = require('googlemaps');
var placeId = '116465254736946820269';
var key = '##############548';
googlemaps.placeDetails(placeId, key, function(err, placeInfo){
    if(placeInfo)
        console.log(placeInfo);
});

My first question is : Do I use Browser API key, or Server API key ?

For me it's more logic to use server API, because requests are made by node.js app server, not the client in his browser...

When I try a Server API key (any IP allowed) I have this :

{error_message: 'The provided API key is expired.', html_attributions: [], status: 'REQUEST_DENIED'}

If I regenerate it, I have the same error, or a new error :

{error_message: 'The provided API key is invalid.', html_attributions: [], status: 'REQUEST_DENIED'}

I also tried a browser API key, but it's an other error :

{error_message: 'This IP, site or mobile application is not authorized to use this API key.', html_attributions: [], status: 'REQUEST_DENIED'}

So how could I make the request ? Please help me.

Thak you.