how i can this log in system with yahoo,twitter,facebook etc - authentication

in many sites i can see
alt text http://img718.imageshack.us/img718/4633/15494794.gif
how i can do that
is must tell every company or what?

It's OpenID. You can implement it in PHP easily by looking for PHP OpenID Libraries/Classes.
See http://openid.net/add-openid/add-getting-started/ to get started on developing authentication with OpenID.
Unfortunately, Facebook and Twitter has a complete different set of authorization api and thus you cannot use OpenID for Twitter and Facebook. Instead you can use their API.

Related

Difference between Google "OpenID Connect" and "sign-in with Google"?

I want users to my website to use Google Accounts to authenticate / sign in to my website. The primary use case being users will edit and generate content and we want to log ownership in a secure way. We are not interested in obtaining users Google data, we just want a means to authenticate users.
After googling, I came across some documentation, which seems to explain how to do this OpenID Connect (OAuth 2.0 for Login). But the documentation immediately says "Note: If you want to provide a “sign-in with Google” button for your website or app, we recommend using Google+ Sign-In, ...", which if you follow the link ultimately takes you to Google+ Sign-In.
What's the difference between these two pages of documentation? Why does the first tell you to go to the second while not saying the first is deprecated? Are both/either suitable for my use case? All it says is "we recommend" I want to know WHY, WHY do they recommend it?
UPDATE: I also found yet another link which seems to be documenting another approach https://developers.google.com/accounts/docs/OAuth2WebServer I think this is just for "Authorization" i.e. authorizing your app to make google api calls to get user data, so cannot be used for authenticating/sign-in.
BTW I'm building my website with a Scala Spray BE REST API & NG JS FE.
A comparison of the two is available here.
Google+ Sign-In with profile scope
Has Google client libraries for authenticating with OAuth 2.0, which includes support for Google+ and other Google services (like getting social information on a user). Also this can make implementing easier and requires less boiler plate code
Has the Google+ Sign-In button to simplify sign-in Has no pre-built widgets
Supports over-the-air Android installs
OAuth login is primarily just for authentication at a lower level, that is by making raw HTTP requests, no API.
OpenID Connect protocols (OAuth 2.0 login)
Google+ Sign-In supports OIDC interoperability if you configure with the openid scope and get the user profile using getOpenIdConnect.
OAuth 2.0 login supports OIDC directly. Use it for signing in users to apps that do not need social features and run on platforms not supported by Google+ Sign-In.

Twitter authentication URL

Which URL I should user for authentication user in the Twitter?
For example, in the Instagram token for user can be received when user click on the following link
https://api.instagram.com/oauth/authorize/?client_id=XXX&redirect_uri=XXX&response_type=XXX
After this its return token and I can work with user profile.
How to build such link for twitter?
Twitter API has several ways to authorize and it depends on what you want to do for determining which approach to take.
The OAuth2 approach that instagram takes is called application-only in Twitter API. The thing about application-only is that you can only use it on endpoints that aren't associated with a user. e.g. it's great for search, but doesn't work well for tweeting (which is something a user would do).
A couple other approaches are Single User Authorization, which is good if your app only needs one set of credentials. e.g. a server app. Another is Pin Authorization which is a work-around for devices that can't manage Web callbacks. These use OAuth 1.0A.
There are a few other OAuth options, but this was just to give you an idea about the available choices and the need to think about what you want to accomplish and match that with what the Twitter API offers. Here's the Twitter docs for more info:
Authentication and Authorization

How do I use OAuth 2.0 just for authentication for Google?

The OAuth2 PHP client code is awesome. It gives great examples on how to use OAuth 2 with Google APIs. The problem is that I only want to use OAuth 2 for authentication NOT for authorization. I've looked around in the API for something that just authenticates but I can't find the right class.
How do I configure the Google PHP client to only authenticate via OAuth?
I considered just authenticating the client (i.e. `$client->authenticate($_GET['token'])) but that's not ideal because the user is still asked to authorize access to different resources. I don't want to see their email, picture, etc. I just want Google to verify that they are who they say they are.
Well, OAuth is an open standard for authorization and not for authentication!
Most providers however give you the chance to query a users profile, so you can authenticate the user. Without the access to his profile data, especially his user id, you can not achieve this.
See Google's documentation for obtaining the user's profile information for login.
If you only want to use authetication you have to use: OpenID / Federated Login.
See: https://developers.google.com/accounts/docs/OpenID

OAuth Issue for Connecting to Twitter API to make user search (users/search)

I am using Twitter API for retrieving user information for specific name searches. The method I am using is users/search. You can find details of this method here: http://apiwiki.twitter.com/Twitter-REST-API-Method%3A-users-search.
Right now I am trying to use OAuth in my application as Twitter announced that they will no longer support basic authentication. The issue with using QAuth is that I don't require the users to connect to their Twitter account and so I can not generate user token. My application is using Twitter just for showing information about people, it's not posting/updating anything. I will really appreciate if anyone has any suggestions on using OAuth for Twitter without using Twitter user's login information.
I would suggest that you create an account for your application and use that account to perform user search if your application is a webapp.
If your application is an desktop app, I think it's understandable to user that they need to authorize your application to do the user search.

Using oAuth (Twitter, LinkedIn) for login to a web app

Should I use oAuth, for example LinkedIn or Twitter, as my signin mechanism for my app? It seems that most apps just use oAuth to connect other services to it, but they make you set up your own user/password after you use oAuth (including StackOverflow), and I'm not really sure why this is. Would love some insight here. Thank you.
Why not use OpenId, to allow people to sign into your application, without having to type any specific login/password ?
Quoting the corresponding wikipedia entry :
OpenID is an open, decentralized
standard for authenticating users
which can be used for access control,
allowing users to log on to different
services with the same digital
identity where these services trust
the authentication body. OpenID
replaces the common log on process
that uses a login-name and a password,
...
BTW, that's exactly how one logs-in on stackoverflow ;-)
OAuth purpose is not authenticating your users with your site, is letting your users allow you (the oauth consumer) access to their protected resources in other sites (oauth providers) like LinkedIn, Twitter, Google APIs etc.
For authentication, you should use OpenId as others have pointed
Twitter provides a Sign in with Twitter flow that is OAuth but provides a faster redirect if it is an existing user of your service and they are already authenticated with Twitter.
http://apiwiki.twitter.com/Sign-in-with-Twitter
If you are building a Twitter centric application this makes a lot of since to use and you won't have to implement an entire alternate authentication method like OpenID.
Be careful if you let users authenticate with both Twitter and LinkedIn as users will inadvertently create two accounts and need them to be merged.
Facebook and Twitter both have the "Login with Facebook/Twitter" APIs to actually allow users to login without having to create an account for your website. Both of them will return you a valid session that may (or may not) expire. So you actually wouldn't have to ask users to decide on a username/password, as you can fetch both from the APIs (you can not get the users email address when using Twitter though)
So why add those functions to your website?
Users are in general more likely to hit the "Login with ..." button than going through the whole mail address authorization process and entering their name, etc...
Linkedin only has OAuth for usage to its API. It will also depend on what type of language you are writing your webapp in, they should have premade wrapper libraries you could tap on to.