Skip to main content

Golang oAuth2 Google Example for Web and API


Introduction

👉 The oAuth2 protocol has almost become a standard for securing websites and API services. Developers no longer need to store and manage userIDs and passwords for their users. Offloading the authentication to OAuth2 providers such as Google, Facebook, Linkedin, Github keeps the authentication with username and password, within those providers rather than passing through the developer’s application. This reduces the risk that an application will leak user credentials and puts more control in the user's hands on for managing authentication with their accounts.

I wanted to provide this capability in my own apps and went looking for a pattern to use in Go. Typically when I’m on a hunt like this I find bits and pieces that I stitch together into a reference pattern. For this oAuth pattern most of the result I found referenced back to a couple limited examples on the google site.

Then it happened, I stumbled on a fantastic write-up and sample app that covers every main point better than I could have written.

Initial Login with oAuth:

In this example, the set is using Google oAuth2 credentials just for the site authentication




var (


 googleOauthConfig = &oauth2.Config{


  RedirectURL: "http://localhost:9000/GoogleCallback",


  ClientID:    "",


  ClientSecret: " ",


  Scopes: []string{"https://www.googleapis.com/auth/userinfo.profile",


   "https://www.googleapis.com/auth/userinfo.email"},


  Endpoint: google.Endpoint,


 }


 oauthStateString = "random"


)


Token Reuse for API calls:

For my use not only did I want to log the user in but I also wanted to use those credentials for subsequent google API calls.


token, err := googleOauthConfig.Exchange(oauth2.NoContext, code)
if err != nil {
 fmt.Println("Code exchange failed with '%s'\n", err)
 http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
 return
}

response, err := http.Get("https://www.googleapis.com/oauth2/v2/userinfo?access_token=" + token.AccessToken)  
Now I can use that info in other handlers to the client and make API calls. And Store in Mysql Database.

Mysql - Database Table  Struct :



type GoogleUserTable struct {


Id            int    `orm:"column(id);auto"`


Name          string `orm:"column(name);size(225)"`


Email         string `orm:"column(email);size(225)"`


Role          string `orm:"column(role)"`


Picture       string `orm:"column(picture)"`


Hd            string `orm:"column(hd)"`


VerifiedEmail int8   `orm:"column(verified_email)"`


AuthId        string `orm:"column(auth_id);size(256)"`


}
we’ve used google OAuth2 to log the user in the mysqli database ,  then we reused those tokens for future calls by the user. This allow us to create an interface to google APIs that act based on the users credentials and access rights.

Source Code link:


OAuth 2.0 client IDs: 

Create credentials to access your enabled APIs.
Labels:

Comments

Post a Comment

Popular posts from this blog

Java Currency Formatter Solution

Given a  double-precision  number,  , denoting an amount of money, use the  NumberFormat  class'  getCurrencyInstance  method to convert   into the US, Indian, Chinese, and French currency formats. Then print the formatted values as follows: US: formattedPayment India: formattedPayment China: formattedPayment France: formattedPayment where   is   formatted according to the appropriate  Locale 's currency. Note:  India does not have a built-in Locale, so you must  construct one  where the language is  en  (i.e., English). Input Format A single double-precision number denoting  . Constraints Output Format On the first line, print  US: u  where   is   formatted for US currency.  On the second line, print  India: i  where   is   formatted for Indian currency.  On the third line...
7 comments
Read more

Java Loops II print each element of our series as a single line of space-separated values.

We use the integers  ,  , and   to create the following series: You are given   queries in the form of  ,  , and  . For each query, print the series corresponding to the given  ,  , and   values as a single line of   space-separated integers. Input Format The first line contains an integer,  , denoting the number of queries.  Each line   of the   subsequent lines contains three space-separated integers describing the respective  ,  , and   values for that query. Constraints Output Format For each query, print the corresponding series on a new line. Each series must be printed in order as a single line of   space-separated integers. Sample Input 2 0 2 10 5 3 5 Sample Output 2 6 14 30 62 126 254 510 1022 2046 8 14 26 50 98 Explanation We have two queries: We use  ...
15 comments
Read more

Java Date and Time Solution | Returns the day on that date.

The  Calendar class  is an abstract class that provides methods for converting between a specific instant in time and a set of calendar fields such as YEAR, MONTH, DAY_OF_MONTH, HOUR, and so on, and for manipulating the calendar fields, such as getting the date of the next week. You are given a date. To simplify your task, we have provided a portion of the code in the editor. You just need to write the method,  , which returns the  day  on that date. For example, if you are given the date  , the method should return   as the day on that date. Input Format A single line of input containing the space separated month, day and year, respectively, in      format. Constraints Output Format Output the correct day in capital letters. Sample Input 08 05 2015 Sample Output WEDNESDAY Explanation The day on August  th    was  WEDNESDAY . impo...
8 comments
Read more