Adding Facebook , Gmail Login to Own Website . Is it free? - facebook

I want to add facebook and gmail login for my application. Does facebook and gmail charge anything for providing login?

No, it is for "free". They however track your users as form of charge.

Related

Can I used passport.js to login to Facebook from an app?

I and a friend are developing an app and would like to use Facebook as a way of users having their own accounts without us having to ask them to store passwords or make users for security and ease of use.
Passport.js has a facebook plugin but it talks about a redirect URL so my question is: is it actually possible to just send information like email address and password to facebook for authorisation and return the users profile without actually redirecting the user to a facebook login page.
I don't see how i could redirect the user to a facebook login while inside my app and also what on earth would i put as the callback URL? Am i just trying to use passport-facebook in the wrong way?
is it actually possible to just send information like email address and password to facebook for authorisation
No. Users are strongly discouraged from giving this information to any 3rd party app, and you are not allowed to ask users for them.
Login with username/email and password happens on Facebook, not in your app. You will get feedback from the login endpoint then that they logged in successfully.

How Disqus facebook login dont have the - 'dont give the site my email' option

when i try to use facebook login in my website and i asked for email adress when the user login facebook ask them something like: do you want to give them your email? yes no.
but when i check Disqus login with facebook, facebook dont give me the option to login but dont give them the email its just say:
DISQUS will receive the following info: your public profile, friend list and email address.
how do i do the same in my website? because right now what i have is that when someone log in with facebook and refuse to give me his mail i just ask them for their mail
so after few days i found it.. by using facebook js sdk and asking for email the user dont have option to refuse

OpenID not working - gmail

I registered with facebook longback using my email ID xxxxxx#hotmail.com.
Now I added my gmail ID xxxxxx#gmail.com
I want to use OpenID for logging into facebook - first I want to log into my gmail using my gmail ID and gmail pasword, then I open facebook in a new TAB (in the same browser) it should not ask for my facebook username & Facebook password.
But it is not working in my case, even after logging in gmail, facebook is asking for facebook user ID and facebook password.
Can you please help with the right procedure for using openID (i.e. gmail login with gmail user credentials for facebook).
I do not think that Facebook supports OpenID login. You either can use OpenID for Google Account or use Facebook's own login scheme and perhaps OAuth too.
https://developers.google.com/accounts/docs/OpenID
https://developers.facebook.com/docs/concepts/login/
https://developers.facebook.com/docs/reference/dialogs/oauth/

LOGIN into facebook or google from another domain

I there anyway to log users to facebook and google gmail, from another domain site?
Or are there specific API to do that?
I'm not talking about fb login or connect or google login API, i'm talking about "triggering" login forms in some whay or launch requests to sites to login in users.
I would like to make users able to log to facebook from another site, setting up cookies, so when he will return to facebook he will be logged, and viceversa.
And if is there, is it legal or not?
Thanks
Thats not possible, since Facebook are the ones that issue the cookies, I think it might be possible to generate a cookie that will log you into Facebook, but it would be illegal. Swift

Oauth : Get user's permissions without any redirection to a server

in my website, I want to add a "invite friend of my contacts book" functionnality.
I would like that the user fills the loggin form in my website. Then the website contacts Google Mail, Yahoo Mail, Live Mail and retrieves the contact list.
In the Oauth protocole supported by Google and Yahoo, the user is redirected to a Google or Yahoo page (like Facebook) in order to permit the user to give permissions.
But I saw two websites which didn't any redirections to get the contacts book (LinkedIn for a Google mail account and Theauteurs with a live mail.)
Do you know how I can get a contacts book without redirect the user to Google, Microsoft or Yahoo website.
Simple. Neither of them are using OAuth to access contact data. That means users don't get the benefits (such as not having to share passwords and easy revocation).
The motivation behind OAuth is to avoid users to input their credentials of site A in site B (this would be you).
If you follow this path (and I believe you should not), you are not doing OAuth at all.
PS: Why Facebook doesn't use OAuth is something that puzzles me still...
Facebook will be dropping Connect in favor of oAuth. Outlined here-> http://www.pcmag.com/article2/0,2817,2362920,00.asp