Foursquare userless search iOS - iphone

is there a way to fetch the venues search in iOS without the user entering his password or showing some foursquare oauth website?
I don't think that this oAuth makes any sense for this kind of request, it should be just an REST api like so "https://api.foursquare.com/v2/venues/search?ll=-27.58818,-48.523248&client_id=JN00ABQBOCK5V54FQ1TWQFLOOIDU12UAZXURHXGXNK0ESJBY&client_secret=14ES1NXTCL1XC5HSLBUT4LWE4ROEDGNYKKWGGERZQGUKQ5JC"
but this one is deprecated =/
Any thoughts?

It's not deprecated, you're just missing the "versioning" parameter that specifies what version of the API you're trying to use.
Requesting https://api.foursquare.com/v2/venues/search?ll=-27.58818,-48.523248&client_id=JN00ABQBOCK5V54FQ1TWQFLOOIDU12UAZXURHXGXNK0ESJBY&client_secret=14ES1NXTCL1XC5HSLBUT4LWE4ROEDGNYKKWGGERZQGUKQ5JC&v=20111107 will remove the warning you saw in your response

Add a query string parameter to your request as follows..
&v=20111119 // Choose a proper version.
Update: this is actually a date. So make sure you send current date in yyyymmdd format against v parameter.

According to FourSquare's docs page on venue searching an acting user is no longer necessary:
Some endpoints (e.g. venue search) allow you to not act as any
particular user. We will return unpersonalized data suitable for
generic use, and the performance should be slightly better. In these
cases, pass your client ID as client_id and your client secret as
client_secret. Although the draft 11 of the OAuth2 spec provides a
mechanism for consumers to act via token entitled Client Credentials,
we do not currently support this.

Related

REST API architecture

I just started to construct REST API refer to this guide.
It's my first time coustructing REST API architecture, so something ambiguous.
POST vs GET
Before learning about REST API, I choose POST when I don't want form-data being exposed(e.g. user's ID, password, phone number).
But in REST API, POST means 'create new resource' if what I learn is right.
If so, what is the proper method for following case :
'check user's ID is duplicate or not', 'find my id or password'
represent specific action
REST API guide says that use noun to represent.
I Usually named function or method by verb+noun combination(e,g, checkId, findPassword).
Then what is proper(or better) way to represent?
GET /user/check-id
GET /user/id/check
GET /user/id/duplicate
Take a look at the RESTful verbs. POST is definitely used to create something, and GET is a query. That being said, you are absolutely right that GET URL Parameters are often logged all over the place, and you should not use them in GET urls if they contain sensitive data.
To check if a user's ID is a duplicate, I'd do a POST with the user's ID, and return a HTTP 409 code if it already exists.
The find password is a different question. In short, don't do it. You should NEVER, EVER, EVER store a user's password in plain-text. Doing so is negligence in today's computing world. Resetting a password should involve creating a password reset request (A POST to a /user/id/reset), which results in a password request being sent via another channel, but never, ever return a password from a GET request.

Creating user record / profile for first time sign in

I use an authentication service Auth0 to allow users to log into my application. The application is a Q&A platform much like stackoverflow. I store a user profile on my server with information such as: 'about me', votes, preferences, etc.
When new user signs in i need to do 1 of 2 things:
For an existing user - retrieve the user profile from my api server
For a new user - create a new profile on the database
After the user signs in, Auth0(the authentication service) will send me some details(unique id, name and email) about the user but it does not indicate whether this is a new user(a sign up) or a existing user(a sign in).
This is not a complex problem but it would be good to understand best practice. I can think of 2 less than ideal ways to deal with this:
**Solution 1 - GET request **
Send a get request to api server passing the unique id
If a record is found return it
Else create new profile on db and return the new profile
This seems incorrect because the GET request should not be writing to the server.
**Solution 2 - One GET and a conditional POST request **
Send a get request to api server passing the unique id
The server checks the db and returns the profile or an error message
If the api server returns an error message send a post request to create a new profile
Else redirect to the home page
This seems inefficient because we need 2 requests to achieve a simple result.
Can anyone shed some light on what's best practice?
There's an extra option. You can use a rule in Auth0 to send a POST to the /users/create endpoint in your API server when it's the first time the user is logging in, assuming both the user database in Auth0 and in your app are up-to-date.
It would look something like this:
[...]
var loginCount = context.stats.loginsCount;
if (loginCount == 1) {
// send POST to your API and create the user
// most likely you'll want to await for response before moving on with the login flow
}
[...]
If, on the other hand, you're referring to proper API design and how to implement a find-or-create endpoint that's RESTful, maybe this answer is useful.
There seems to be a bit of disagreement on the best approach and some interesting subtleties as discussed in this post: REST Lazy Reference Create GET or POST?
Please read the entire post but I lean towards #Cormac Mulhall and #Blake Mitchell answers:
The client wants the current state of the resource from the server. It is not aware this might mean creating a resource and it does not care one jolt that this is the first time anyone has attempted to get this resource before, nor that the server has to create the resource on its end.
The following quote from The RESTful cookbook provided by #Blake Mitchell makes a subtle distinction which also supports Mulhall's view:
What are idempotent and/or safe methods?
Safe methods are HTTP methods that do not modify resources. For instance, using GET or HEAD on a resource URL, should NEVER change the resource. However, this is not completely true. It means: it won't change the resource representation. It is still possible, that safe methods do change things on a server or resource, but this should not reflect in a different representation.
Finally this key distinction is made in Section 9.1.1 of the HTTP specification:
Naturally, it is not possible to ensure that the server does not
generate side-effects as a result of performing a GET request; in
fact, some dynamic resources consider that a feature. The important
distinction here is that the user did not request the side-effects,
so therefore cannot be held accountable for them.
Going back to the initial question, the above seems to support Solution 1 which is to create the profile on the server if it does not already exist.

How to design URL to return data from the current user in a REST API?

I have a REST based service where a user can return a list of their own books (this is a private list).
The URL is currently ../api/users/{userId}/books
With each call they will also be supplying an authentication token supplied earlier.
My question(s) is:
Is supplying the userId in the URL redundant? As we get a token with each call we can find out which user is performing the call and return their list of books. The userId is not strictly required.
Would removing the userId break REST principles as /users/books/ looks like it should return all books for all users?
Should I just bite the bullet and authenticate them against the token and then check that the token belongs to the same userId?
Short answer
You could use me in the URL to refer to the current user. With this approach, you would have a URL as following: /users/me/books.
An answer for each question
Is supplying the userId in the URL redundant? As we get a token with each call we can find out which user is performing the call and return their list of books. The userId is not strictly required.
You could consider doing something like this: /users/me/books. Where me refers to the current user. It's easier to understand than /users/books, which can be used to return all books from the users.
For some flexibility, besides /users/me/books, you could support /users/{userId}/books.
The URL /users/me can be used to return data from the current user. Many APIs, such as StackExchange, Facebook, Spotify and Google+ adopt this approach.
Would removing the userId break REST principles as /users/books/ looks like it should return all books for all users?
I don't think it will break any REST principles, but I think your resources will not be properly indetified. As I answered above, I would use /users/me/books and also support /users/{userId}/books.
Should I just bite the bullet and authenticate them against the token and then check that the token belongs to the same userId?
When using the userId in the URL to request private information from a user, there's no harm in checking if the token belongs to the user with the userId included in the URL.
I dont think that removing userId would break any REST principles, because after all, /users and them /books, its a little bit openend to interpretation and REST says basically nothing about it, on the other way if you are going to stay with the id inside the request, you MUST check that the user id is the same as the connected user, anyways, for me the 1 is redundant because you already have that information, plus, every time you are going to make useless checks because anyways the authentified userId is the one that you are going to trust in all cases.
Best Regards
REST is resources oriented so in your point what is the resource user or book. My point of view it's book. And I think you can request this resources
/api/books?user={userid}
But this URL can not solve your permission issue so you have to do it in your code with token information you can get with a OAuth2 protocol or whatever.

How to pass Facebook Id from client to server securely

I have a Facebook canvas app. I am using the JS SDK to authenticate the user on the browser-side and request various information via FB.api (e.g. name, friends, etc.).
I also want to persist some additional user information (not held on Facebook) to the database on my server by making an ajax call:
{ userFavouriteColour: "Red" }
To save this on the server and associate with the correct user, I need to know the Facebook uid and this presents a problem. How do I pass the uid from the client to the server.
Option 1: Add uid to the ajax request:
{ uid: "1234567890",
userFavouriteColour: "Red" }
This is obviously no good. It would be trivial for anyone to make an ajax request to my web service using someone else's Facebook Id and change their favourite colour.
Option 2: On the server, extract the uid from a cookie:
Is this even possible? I have read that Facebook sets a cookie containing the uid and access token but do I have access to this cookie on my domain? More importantly, can I securely extract the uid form the cookie or is this open to spoofing just like option 1.
Option 3: User server-side authentication on the server:
I could use the server-side authentication to validate the user identity on my server. But will this work if I am already using client-side authentication on the browser? Will I end up with two different access tokens? I would like to make FB.api requests from the browser so I need the access token on the client (not just on the server).
This must be a very common scenario so I think I'm missing something fundamental. I have read a lot of the Facebook documentation (various authentication flows, access tokens, signed_request, etc.) and many posts on SO, but I still don't understand how client-side authentication and server-side authentication play nicely together.
In short, I want to know the user's identity on the server but still make requests to the Facebook api from the client browser?
(I am using ASP.NET and the Facebook C# SDK on the server)
EDIT: Added bounty. I was hoping to get a more deifnitive, official recommendation on how to handle this situation, or even an example. As said, I have already read a lot of the official FB docs on authentication flows but I still can't find anything definitive on how client-side and server-side authentication work together.
Option 1:
The easiest way I can think of is to include the accessToken in JS and pass it with the ajax call.
Option 2:
Using the same as option 1, but instead of sending just the accessToken, send the signedRequest.
On the server side you can decode it using (TryParseSignedRequest method) which will give you the UserID :-)
Note: signedRequest is encrypted with the application Secret. you are the only one who should know it, so you are safe on that end.
Disclaimer:
I have no coding experience in C#, but a little search in google gave me this:
Facebook C# SDK for ASP.NET
Making AJAX Requests with the Facebook C# SDK
It's very simple actually.
When the user loads you app use the server side authentication, get the access token and load the user data by issuing an api request from the server.
On the server side you'll have everything you need and it's sandboxed.
When the page renders for the user, using the js sdk get the user authentication data, you should be able to use FB.getLoginStatus since the user already went through the server side authentication.
Now on the client side you also have an access token which you can use to get the user data from the graph api.
The two tokens will be different, and will also have different expiration, but that should not be a problem, both token should work properly as you'd expect them to.
Since both sides have their own token and a way to make requests to the api, there's no need to send any fb data between them.
So the 3rd option you mentioned, to me, sounds the best, and it's really simple to implement that too.
Edit
All facebook SDKs are just wrappers for http request since the entire fb api is made on http requests.
The SDKs just give you easy and shorter access to the data with out the need to build the url yourself (with all the different possible parameters), make the request and parse the response.
To be completely honest, I think that stop providing a way for the C# SDK to support server side authentication is a very bad decision.
What's the point in providing a SDK which does not implement the entire api?
The best answer to your question, from my experience, is to use both server and client side authentication, and since the C# SDK does not support it, my advice to you is to create your own SDK.
It's not complicated at all, I already implemented it for python and java (twice), and since you'll be developing it for your own needs it can be tailored for your exact needs, unlike a public SDK which should support all possible options.
2nd Edit
There's no need to create a completely new SDK, you can just "extend" the ones you're using and add the missing parts that you need, like sever side authentication support.
I don't know if it's language specific but using both server-side and client-side authentication does no harm.
You can work on option 2 but yes, that will be also vulnerable to spoofing.
Doing option 3, you will be having a single access token for that user session, so that would be the best choice according to me since you always have chance of spoofing when passing user information from client side.
I had exactly the same question recently. It's option 2. Check this post from the Facebook blog.
To be honest I am not enough of a hacker to know if you could spoof the UID in the cookie, but this seems to be the 'official' way to do it.
EDIT: to the other question under option 2, yes, I believe you have to access this cookie on your domain.

How do i use an API

I've never used an API and was wondering how you use them... I would like to use facebook, twitter and vimeo's api,
Can someone explain the basics of using them, how do i access them and use them etc.
Please and thanks
Neil
How to use an API depends on the API. Usually the API creator has documentation on how to use their specific API.
Mostly, things work like the following:
You register to get a developer key. Then, you send requests to the service via HTTP (for example Twitter is using REST, which requires you to send XML or JSON to a specific http-URL providing your key). You get an answer from the service, which you must then parse and react to accordingly (for example filling a list with contacts, etc.).
Most of the time this all comes down to:
Create an XML or JSON document that describes the call parameters
Send the document to an URL using GET, POST or other request methods
Get the server's response
Parse and evaluate the response
The specific ways to use the API, especially performing authentication, can be found on the service's developer pages.
The best way to start if you want to use an API is to read it's documentation, find some tutorials and code examples. This is always/usually published by the one offering an API.
Good luck :)