In this post, I will be sharing my thoughts apart from standard design practices. How can caching be implemented on the server or client side when no session info is allowed to be stored on the server? Excellent, Excellent Tutorial. I don't know of a REST constraint which has problem with that kind of technology. Let us know if you liked the post. I'm reading Roy Fielding's dissertation Architectural Styles and the Design of Network-based Software Architectures, which introduces the REST architectural style. How to clamp an e-bike on a repair stand? Cookie-based session must be used only for own(!) Why does hashing a password result in different hashes, each time? logically there's nothing stopping you from performing the authentication on every request. I am an SAP ABAP developer who is trying to learn OData which uses RESTful architecture. transitions that it provides, with the transitions limited to a Site design / logo 2022 Stack Exchange Inc; user contributions licensed under CC BY-SA. REST was just one example. What it all boils down to is that you need to make sure your authentication tokens are validated against a backing store of some sort (database, cache, whatever) to ensure that you preserve as many of the REST properties as possible. You could store a cookie on a path that is not used by your server. you can use OAuth, API Key (public /private) or other authentication system. Well, this constraint is optional. In the following blog post, Roy Fielding gave a nice summary of the whole REST idea: http://groups.yahoo.com/neo/groups/rest-discuss/conversations/topics/5841, "A RESTful system progresses from one steady-state to the @Ravi I have found JSON Web Tokens (JWTs) great for authentication/authorization when implementing RESTful API. i think token must include all the needed information encoded inside it, which makes authentication by validating the token and decoding the info For me there are not many ways to maintain a session over HTTP. Thanks for the comment. Its always better to synonymize a resource with a web page.

As Im new to APIs this really gave me the explanation I needed to the meaning of REST. Today, this is standard practice in web development, so nothing fancy is required from your side. Or you set a persistent cookie with some hash (if it is registered on the server as a resource for a long while). That said, authentication tokens must be stored in a way that allows all possible clients to continue granting access during their valid times. (Depending on the scope of the answer I may be better off opening a new question for that). If it matters, I assume I'm running a javascript app in the browser. The server side implementation does not need to concern the client as long as the server behaves RESTful.

Hey Zane, One example is that you can store the data being returned from the API, which is agnostic of who requests it. https://www.oauth.com/oauth2-servers/access-tokens/self-encoded-access-tokens/. @JonathanvandeVeen yes, of course you store it. , Great explanation. Cheers !! OAuth. information necessary to understand the request, and cannot take Non of the applications built today has its application state driven solely by hypermedia. You don't have to use cookies, but if you have secured resources (eg my shopping basket as opposed to your basket) then you do need some way to detect which request corresponds to which of us. Could you right whatever misunderstanding I have here please?

From my point of view: As such, to the client, a session cookie is exactly the same as any other HTTP header based authentication mechanism, except that it uses the Cookie header instead of the Authorization or some other proprietary header. JWT vs cookies for token-based authentication. If the basket is held in a cookie, Logging in on a different client will not show my basket. I'm honestly not sure how Google does it, but the expiration time could be encoded into the authentication token. Notice that all the above constraints are most closely related to WWW (the web). Connect and share knowledge within a single location that is structured and easy to search. This constraint essentially means that client applications and server applications MUST be able to evolve separately without any dependency on each other. I don't remember such an issue. one state at a time (the current steady-state) and thus each If your REST API has a different domain than your client, then set cookies only on the client domain and access their content for example with client side javascript if we are talking about browsers. All resources should be accessible through a common approach such as HTTP GET and similarly modified using a consistent approach. Fielding's dissertation: Question about trade-offs for the uniform interface constraint (5.1.5 Uniform Interface), Security Issues with RESTful Authentication & Session Management. What does function composition being associative even mean? If chaching is done on Server side, does it not break the Stateless contraint? The only problem was with the concept of creating authentication token on the server. How should I deal with coworkers not respecting my blocking off time in my calendar for work? I imagine you could use some unique identifier that is known to the client, and use that as a mapping between client and secured user id after login instead, but they're hard to come by and maintain security. a complex state diagram, but each user agent is only able to see You don't need more to do this than HTTP basic auth and an encrypted connection: You probably need an in-memory auth cache on server side to make things faster, since you have to authenticate every request. So if I have a RESTful API - for an online store for example - and I want to persist user state client side for a long time - between multiple sessions, are there any alternatives to using cookies to persist local state in modern browsers? So, the client keeps track of what the user is doing, and only sends logically complete state transitions to the server. It is particularly enlightening with regard to what the tenets of REST are actually arguing for and why. How do the electrical characteristics of an ADC degrade over lifetime? This really isnt explained very well. @JonathanvandeVeen yes, you aren't allowed to have a per-user "session" or "basket" type storage on the server in any kind of persistence. What are the "disks" seen on the walls of some NASA space shuttles? The main determiner is this: if you send a REST call, which is a URI, then once the call makes it successfully to the server, does that URI return the same content, assuming no transitions have been performed (PUT, POST, DELETE)? If the client application needs to be a stateful application for the end-user, where the user logs in once and does other authorized operations after that, then each request from the client should contain all the information necessary to service the request including authentication and authorization details. I would rephrase your initial statement. This test would exclude errors or authentication requests being returned, because in that case, the request has not yet made it to the server, meaning the servlet or application that will return the document corresponding to the given URI. Using RESTful APIs, you can do the same thing with your web services what you do to web pages. It is permitted. next, and each such steady-state is both a potential start-state Persistent RESTful state on client without cookies, How APIs can take the pain out of legacy system headaches (Ep. If so, then wouldn't it be RESTless? In the case of session cookies, your session will be lost. So it must be possible. They require an authentication header with the user's authentication key to be passed upon every request. There's HTML5 local storage, which allows you to keep data without it contaminating the HTTP requests you make.

Another client with identical request information would be taken to a different location depending on the server-side state. Thoughts? So how do you actually handle the checkout in your example? For example, as the user enters data into a GUI screen, the client is keeping track of what fields have been entered, which have not, any required fields that are missing etc. We next add a constraint to the client-server interaction: A client should know only resource URIs, and thats all.

but if the cookie holds the authentication token itself it's a feasible solution. Using cookies (or local storage) does not violate Rest since it is related to the first. How to help player quickly make a decision when they have no way of knowing which option is best. This really needs a deeper explanation, with concrete examples of what violates the stateless constraint, and why caching does not violate the constraint. RESTApi is over http, it could accessed by browser. list of holidays in calendar year then you can mark the API as cacheable so client applications can create their own cached version of response and avoid one additional network call, completely. Is the fact that ZFC implies that 1+1=2 an absolute truth?

[15] If a service violates any What are cookies and sessions, and how do they relate to each other? You may not agree with me on a few points, and thats perfectly OK. The thing here is that every request to be fulfilled on the server needs the all necessary data from the client. Any client issuing an identical request (same headers, cookies, URI, etc) should be taken to the same place in the application. number of components obeying a simple set of rules such that they To subscribe to this RSS feed, copy and paste this URL into your RSS reader.

@Darrel A fair enough point. Accepted your answer because of the nice charts. Thanks. Cookie blocked/not saved in IFRAME in Internet Explorer, Can you help me understand this? As such, cookies by themselves should not make an API RESTless, and sessions are simply cookies to the client. REST stands for Representational State Transfer, a term coined by Roy Fielding in 2000. This question is related a similar question about cookies for authentication in REST but in my case I am not concerned with authentication strategies - just in how to persist state between sessions without sending state to the server. I dont think there will be any system performance downgrade due to number of paratemeters considering huge processing power of todays hardware. Whenever relevant, a resource should contain links (HATEOAS) pointing to relative URIs to fetch related information. Is there a response error defined that the server can/should return if it receives a GET request exceeds this length? Why is it common to put CSRF prevention tokens in cookies? such that each request from client to server must contain all of the If cache storage fill up, cache will be invalidated more often and there will be more server hits than expected. The idea behind statelessness is that the SERVER is stateless, not the clients. In this case the service directly changes the client state. If we accept this then you are using tokens as most authentication systems do, in which case whatever mechanism we use to scale the tokens repository will have mostly equal scalability concerns as any session scalability. Thanks for creating this complete guide as well, super useful! Remember, for any parameter change in URL, there will be a new entry in cache. How did this note help previous owner of this old film camera? If the website stored the current location of the user and managed navigation by updating this server side navigation variable, then REST would be violated. Statelessness Really means when 2 requests arrive at the server, the server doesnt know if this request is a continuation of prior request or not. I know that if there is no persistence server side, then I can't share my basket between multiple devices, for example, but I just wanted to know about client-side state persistence techniques. As I understand, there are two types of state when we are talking about sessions. In complex business cases, in healthcare, for example, RBAC is absolutely common and necessary. other HTTP header based authentication mechanism, except that it uses I think the important part is that. You can now choose to sort by Trending, which boosts votes that have happened recently, helping to surface more up-to-date answers.

Then this is considered as stateless. Which term? You are doing a Wonderful Job Lokesh !! Not truly does not tell us anything useful we cant even quantify how close to REST. All the above constraints help you build a truly RESTful API, and you should follow them.