i am trying to use rest api but don't understand where,why and when i should use this - api

What is the purpose of rest API and where it should be used how can i know that in this part of website i should use rest API any one can tell me in simple words why,where and how can in implement that technology ?

My answer might be not througout and lacking in precision, but it may do.
REST API means serving app (website) API through HTTP requests (mainly)
Thats simple/silly explanation.
Better one is here:
What exactly is RESTful programming?
About when to use it... well.. that depends.
I guess common use case is when you want to expose some part of data/functionality of your site for third party developers. Then you may define URL under which you would return data in json or xml or....

Related

Can I use just DirectusSDK instead of REST or GraphQL?

Are there any downsides to use directusSdk instead of making GraphQL requests?
According to documentation; My front-end can log in users and make requests through javascript SDK.
I would say using the SDK is a great option and is something I choose to do myself where possible, I believe that the Directus application uses it too, therefore it is well looked after 😌

is google maps API based on REST?

I still don't know if google maps API uses the SOAP protocol or if it's a RESTful service. I've read its documentation but it doesn't say anything about that.
I know this is an old question but I wanted to try to give an answer anyway, because I do not agree with the logic in #Brick's answer (supports JSON and XML, therefore is RESTful).
There are quite a few different Google Maps APIs, so it is hard to answer your question without you specifying which one you mean. However, for an API to be RESTful, it has to comply with the following five or six constraints:
Client-Server
Stateless
Cacheable
Layered system
Code on demand (optional)
Uniform interface
So an API supporting JSON and XML might, or might not be, RESTful, depending if it complies with the constraints above.
I think Google Maps API is not a REST API.
Google maps API give us tools, methods and objects, when we include its API, We can use these methods to build a map, we need to give data to these objects in order to build our map.
So, we are not really asking for a REST resource, we don't use a REST client to access it and we don't get json or xml data.
A rest API works with standard HTTP methods (like GET, PUT, POST, and DELETE) and returns/add/edit/delete data from its resource.
REST does not enforces message format as XML or JSON or
but it supports both. But SOAP is XML based message protocol it doesnt support JSON.
Since Google Map APIs support both json and xml , it can be safely said they they are implemented in REST.
Further if you look at the URI of google map api , you will see that they are resources based just like REST URI should be ,for example to get the directions resource you hit this URI
- https://maps.googleapis.com/maps/api/directions/json?origin=Boston,MA&destination=Concord,MA&waypoints=Charlestown,MA|Lexington,MA&key=YOUR_API_KEY

Are REST API's really RESTful?

I'm new to this game so I might be misunderstanding things. Actually, if someone tells me that I'm misunderstanding things, it will be a favor. Maybe this person will be considerate enough to show me the right path. But...
One of the "guidelines" or "best practices" of REST as it applies to Web Services (http://en.wikipedia.org/wiki/Representational_state_transfer#Applied_to_web_services) is that you should use the proper HTTP methods when making calls (did I misunderstand it?) to REST API's.
But looking at many API implementations on the web, what I see is that 100% of the calls made to them are actually GET calls that, depending on their URI, will be interpreted by the API as being of one of the HTTP verbs or methods.
So, for example, looking at the REST API documentation for Twitter (https://dev.twitter.com/rest/public) which, in principle, only defines two verbs/methods (GET and POST), actually have all calls sent as GET and, based on the URI in the GET call, are interpreted by the API and acted upon.
Example:
GET statuses/lookup: https://api.twitter.com/1.1/statuses/lookup.json
POST statuses/update (PUT?): https://api.twitter.com/1.1/statuses/update.json
In both cases, the call itself was made using GET and the last part of the URI defined it as a real GET or as a POST.
In summary, to be truly RESTful, shouldn't client side implementations of REST API's for web services use the proper HTTP verbs/methods?
What am I missing?
You're missing a lot, but don't worry about it, most people are.
The fact is that very few so-called REST APIs publicly available on the internet are really RESTful, mostly because they are not hypertext driven. REST became a buzzword to refer to any HTTP API that isn't SOAP, so don't expect for an API to really be RESTful just because it says it's a REST API. I recommend reading this answer.
From my experience, most API developers aren't aware what REST really is and believe any HTTP API that uses HTTP and avoids verbs in URIs is REST.
REST is defined by a set of constraints. Among them is the uniform interface, which in simple terms means that you should not change the expected behavior of the underlying protocol. REST isn't coupled to any particular protocol, but since it's common to be used with HTTP, they get convoluted sometimes.
HTTP has very well defined semantics for the GET, POST, PUT, DELETE, PATCH and HEAD methods, and the POST method has its semantics determined by the server. Ideally, a REST API should respond to the methods other than POST exactly as determined in the RFC 7231, but as you noticed, there are many APIs who call themselves REST but don't do that. This happens for many reasons. Sometimes there's a simple misunderstanding about the correct semantics, or it's done to keep consistency, or because of backwards compatibility with intermediaries that don't support all methods, and many other reasons.
So, there's a lot more that has to be done to be truly RESTful other than using the HTTP methods correctly. If an API doesn't get even that right, it needs to find another buzzword, because it's definitely not REST.
I can't exactly tell what your question is, but I believe there are some concepts that will help you. Allow me to elaborate...
You are correct that many APIs use a limited number of HTTP "verbs" in their API. GET/POST are the most common. PUT less so, and then all others (DELETE, HEAD, OPTIONS etc) are used with vanishing probabilities.
Dropbox Core API for file uploads allows optional PUT / POST and their stated reason is "For compatibility with browser environments, the POST HTTP method is also recognized."
Indeed the limitation is the browser. Popular web servers have no problem with all HTTP request methods and even made up ones. After all, the request method is just some string with regard to the web server.
HTML4 and HTML5 only allow GET and POST requests for form requests. If you want your API to be used through a browser at all - and hey why not, it sounds like a useful thing - then you're limited to GET/POST. For a useful discussion on this see: https://softwareengineering.stackexchange.com/questions/114156/why-are-there-are-no-put-and-delete-methods-on-html-forms
Further complicating things is the fact that REST is not an industry standard. There exists no RFC, ISO or other document detailing what a "compliant" implementation must and must not do. While many folks have been playing concepts related to REST for some time, the REST concept was "invented" in the PhD disseration of Roy Fielding. A fantastic read if you're interested in such things.
Yes, according to REST, APIs should be using the correct verbs. However, as long as the documentation is clear and all GET requests are idempotent, then life should continue smoothly.
(Source: I wrote PipeThru.com which integrates 40+ APIs, Dropbox and Twitter included)
I think that this link could give you some hints about the design of RESTful services / Web API: https://templth.wordpress.com/2014/12/15/designing-a-web-api/.
It's clear that not all Web services that claim to be RESTful are really RESTful ;-)
To be short, RESTful services should leverage HTTP methods for what they are designed for:
method GET: return the state of a resource
method POST: execute an action (creation of an element in a resource list, ...)
method PUT: update the complete state of a resource
method PATCH: update partially the state of a resource
method DELETE: delete a resource
You need to be also to be aware that they can apply at different levels, so methods won't do the same things:
a list resource (for example, path /elements)
an element resource (for example, path /elements/{elementid})
a field of an element resource (for example, path elements/{elementid}/fieldname). This is convenient to manage field values with multiple cardinality. You don't have to send the complete value of the fields (whole list) but add / remove elements from it.
Another important thing is to leverage HTTP headers. For example, the header Accept for content negotiation...
I find the Web API of Github well designed and its documentation is also great. You could browse it to make you an idea. See its documentation here: https://developer.github.com/v3/.
Hope it helps you,
Thierry
You are correct. If they want to be "RESTful", their API should respect the semantics of each HTTP method.
Roughly, REST is about method Information (what the server should do), scoping information (where the server should do it) and, I almost forgot to mention, hypermedia driven (make sure you check #PedroWerneck's great answer to this question as it talks about it a little more and referecences a blog post from Fielding on the matter).
What the API you mentioned does is have both method and scoping information in the URL. That would not fit the RESTful architecture very well, as it, in general terms, tells us to:
1) use the HTTP methods the proper way (respecting their properties, such as idempotency and others), and
2) use unique URIs to identify unique resources.
Point 1 says "use HTTP methods to convey method information" and point 2 says "use URIs to convey scoping information".
Again, if an API uses GET with a specific parameter in the URI to do something (and not get something), then it is using URI to convey method information.
Now, don't be alarmed. Most APIs out there are just RESTful-ish (like twitter's of flickr's), meaning they are an animal between REST and something else. That is not bad per se, it just means they will not fully benefit from what RESTful architectures (and HTTP) have to offer.
Remember that being RESTful isn't just a matter of fashion, it does have its benefits, such as statelesness, adressability, and so on. And those can only be fully achieved by using the HTTP verbs like they were supposed to be used.
About using POST instead of PUT, considering they have different properties (PUT is idempotent, POST is not), it is not bad to use POST, as long as it is uniformly designed, that is, a programmer should not wonder what POST will do for each and every URI in the API: they all should behave the same. (PUT does not suffer from that because it already is uniform.) I talked a little more about this - and quoted Roy Fielding's say on it - in another question (check out the "Wrapping Up" part).
Consider looking at REST Richardson Maturity Model topic.
This specification is about how much RESTful particular API is:
Level 0:
Simple GET and POST request to descriptive url
/getUserByName?name=Greg
Level 1:
Divide all content in resources and define actions in resource group
/user/getByName?name=Greg
Level 2:
Proper use of HTTP verbs.
GET /user/Greg
Level 3:
Use hypermedia controls
Different APIs in interent implement different maturity level of REST. That's why some APIs don't support all HTTP features.

Is a restful API and a backend service (like Parse) the same thing?

Rest confuses me sometimes. I know that it involves creating an API layer over your data and then you make calls to that data through the API. The best way I think of Rest is that the actual Twitter website interfaces with the data-layer through API calls.
That made me wonder then: Is a backend-service like Parse also a Rest API to your data?
What might be the difference between Parse and say, building your own Rest API like this guy did: http://coenraets.org/blog/2012/10/nodecellar-sample-application-with-backbone-js-twitter-bootstrap-node-js-express-and-mongodb/ (he's getting some solid google rankings for his API tutorials).
A simple yes/no might answer the question, but providing details will really be appreciated.
I look forward to the answers.
Parse is built around a restful API just like most, if not all, other mBaaS out there.
A RESTful Api isn't just CRUD operations though nor is it the same thing as Parse. Parse is a company that provides a remote backend to developers using a RESTful api.
RESTful api !== BaaS
I have dealt with about 5 mBaaS and Parse isn't really one of them, but I've glanced at their API reference for JS and I think they use mongodb clusters. An mBaaS usually provides the developer the ability to have cloud storage, push notifications, server side code, easier social media integration, and mobile analytics. So it's not just any backend. Although there are some mBaaS, like Urban Airship, that only supply push notifications to developers.
A RESTful api at it's core usually has some key functions that are centered/wrapped around an httpRequest
They usually use "GET", "POST", "DELETE", and "PUT" to make all calls. Some allow the implementation of rpc for custom server logic. An mBaaS takes a lot of work to implement right and well. You can't build Parse in a Day. It takes a lot of planning and such. The differences between Parse and that guy in link are in the implementation, range of features, and purpose in general(the audience).
To better understand REST maybe look here you can also read the HTTP spec if you are feeling adventurous.

Why should we use twitter api insted of getting it from the non-api URL?

I was wondering if i can use the PHP library of Brandom
http://viralpatel.net/blogs/demo/Twitter.class.php.txt
Instead of using the twitter API which has rate limit.
What about using this:
http:// twitter.com/users/show/'.$id.".$format";
Instead of this:
https:// api.twitter.com/1/statuses/show/'.$id.".$format";
The 2nd one uses the API. The first one...i guess it doesn't.
So... can i use the fist one for this same purpose?
THanks.
Reasons you might want to use Twitter API:
Well documented and easy to comprehend
Proper explanation for the caught exception
Most reliable and real time results
Many dimensions to extract the data
Active community that resolves the issues(bugs, confusions ..etc). Also as the developers are Twitter guys, nothing could be more reliable as they know their product better.
Last but not the least, very easy to use
As far as "Rate Limit" is concerned, it can be dealt using Streaming API.