Is OAuth a must before using Google+API - oauth

Question

I m trying to use get and list method with google plus comment. In official site it said (All API calls require either an OAuth 2.0 token or an API key. ) and I have tried send GET request without the step of OAuth it works it returns json format data. My question is OAuth must require before using google+ API?

Answer 1

It depends on exactly what data you're trying to get.
https://developers.google.com/+/api/oauth documents the benefits of using OAuth, but in general, if you want to get private profile data, or if you wish to use the /me/ URL shortcut, you will need to use OAuth and may, if you wish, use an App Key in addition. If all you're interested in is public data, you can use the App Key.

Answer 2

The short answer to whether you can do it is that you can get comments from Google+ without OAuth.
As for the how would you do this, I'm not sure which language you're doing this in but the following code shows how this is done in JavaScript.
The API calls used here can be experimented with in the API explorer:
Listing Activities
Listing Comments
A demo of this code is here.
You will need an API key (the simple key) for a project with the Google+ APIs from the Google APIs console. When you set up the project, you will only need to enable the Google+ API from the services section.
First, grab the activities using the public data API:
// Gets the activities for a profile
function getActivities(profileID){
var activities = null;
var URL = "https://www.googleapis.com/plus/v1/people/" + profileID + "/activities/public?alt=json&key=" + key;
var request = new XMLHttpRequest();
request.open('GET', URL, false);
request.send(); // because of "false" above, will block until the request is done
// and status is available. Not recommended, however it works for simple cases.
if (request.status === 200) {
if (debug) console.log("retrieved activities \n\n");
var activities = jQuery.parseJSON(request.responseText).items;
console.log("Discovered " + activities.length + " activities");
}else{
handleRequestIssue(request);
}
return activities;
}
The following code loops through the activities
for (var i=0; i < activities.length; i++) {
console.log("trying to do something with an activity: " + i);
var activity = activities[i];
console.log(activity.id);
}
Next, you can use the activity IDs to retrieve the comments per activity:
function getCommentsForActivity(activityID){
var comments = "";
var URL = "https://www.googleapis.com/plus/v1/activities/" + activityID + "/comments?alt=json&key=" + key;
var request = new XMLHttpRequest();
request.open('GET', URL, false);
request.send(); // because of "false" above, will block until the request is done
// and status is available. Not recommended, however it works for simple cases.
if (request.status === 200) {
if (debug) console.log(request.responseText);
var comments = jQuery.parseJSON(request.responseText).items;
if (debug){
for (comment in comments){
console.log(comment);
}
}
}else{
handleRequestIssue(request);
}
return comments;
}
function manualTrigger(){
var activities = getActivities("109716647623830091721");
}
The following code brings it all together and retrieves activities and comments for a specific post:
$(document).ready(function () {
var renderMe = "";
var activities = getActivities("109716647623830091721");
console.log("activities retrieved: " + activities.length);
for (var i=0; i < activities.length; i++) {
console.log("trying to do something with an activity: " + i);
var activity = activities[i];
renderMe += "<br/><div class=\"article\"><p>" + activity.title + "</p>";
console.log(activity.id);
// get comments
var comments = getCommentsForActivity(activity.id);
for (var j=0; j<comments.length; j++){
renderMe += "<br/><div class=\"comment\">" + comments[j].object.content + "</div>";
}
renderMe += "</div>";
}
console.log("I'm done");
document.getElementById("ac").innerHTML = renderMe;
});