I have a Spring-MVC webapp (3.0.5-RELEASE) which needs to access JSON webservices from another webapp on a different sub-domain (from the client/browser via AJAX).
I've solved this in the past by either:
writing a simple controller that proxies the requests, using Apache Commons HttpClient to handle the requests. Thus overcoming the cross-site/cross-origin request security limitations of most browsers
implementing a JSONP service on the server side (when calling our own JSON services) - not always possible
In the case where JSONP is not possible, is there a better way of doing (1.)?
and/or
Is there a library that will handle this for me? So I don't have to write all the HttpClient code myself - its not a lot of code, but I wonder if I'm (badly) re-inventing the wheel.
I have often had to consume third party web services (API), and as you mentioned, JSONP is not always an option. This is how I go about designing:
If the API is user centric, it has to provide a jsonp interface and that's what I will use. User centric means that you cannot perceive any reason to call the API, do some computations with the response, may be call one of your ajax services and then combine the response and show the user.
If my use case includes calling the API, and then acting on the response, like calling additional services from my application, combining the data and then showing it to the user, I would prefer not doing this in the browser. I would instead use RestTemplate and make backend api calls to the service. In which case there are no cross domain restrictions.
The only case where using a Server Proxy to bypass jsonp is when you are creating a Product that allows people to build custom plugins, plugins which are hosted on your page, but need to make Ajax calls to the app developers servers. This is a very involved case! (As as example look at how Apigee creates Public Facing REST API around your existing urls, or how Zendesk allows you to develop apps)
Hope this helps.
Related
I need to consume REST API. There are many REST clients for Java. Are there any areas of concerns before proceeding this?
You can use HttpClient for that. However, if you are working on a spring enabled project, I would recommend using RestTemplate.
Rest template provides an abstraction over HTTP client as a result of which you will not have to deal with serialization/deserialition, error handling, SSL configuration in every part of code where you make a REST call. You will just need to configure those with REST template configuration once and not worry about it. This makes your code clean and easily maintainable in case you wish to change the way your application talks to the back-end restful application in future.
I need to develop a client interface to rest webservices in Java.
The idea is to provide a form-gui that permits to choose the url, method, Headers, cookie and body (for post request)
and then clicking on the submit a generic rest Proxy client method is called, this set up the informations and invokes Jersey / JAX-RS client methods (via a series of if / then condition).
In order to not to reinvent the wheel, is there something already built to allow that?
Thank you!
We usually use Chrome REST console in order to do that:
https://chrome.google.com/webstore/detail/rest-console/cokgbflfommojglbmbpenpphppikmonn
It's pretty useful but still have some limits, for instance when you need to change the UserAgent.
In those specific case I recommend the old commands curl or wget.
EDIT: this client proved to be even more useful: https://chrome.google.com/webstore/detail/advanced-rest-client/hgmloofddffdnphfgcellkdfbfbjeloo
It allow you to save your favourite HTTP request to your service.
You can use Rest Client in Firefox or Advanced Rest Client in chrome. They are actually plugins for each browser.
Not being familiar with REST and after reading some doc about it I am a little bit confused about the way it works.
I actually want to use Twilio SMS Gateway that provides a REST API to interact with and send text messages from an existing web-application.
From what I understand, REST is a way to structure a web service and in the end, instead of using SOAP for example, we just access 'resources' with URLs, relying on HTTP to GET, PUT or DELETE data.
The SMS Gateway I am talking about is providing a Java API that I could integrate to my web-app. The classes in this API uses httpcore, httpclient and commons-codec jars. Is this because REST rely on HTTP?
So basically, their API is relying on the Apache and HTTP libs to construct HTTP requests in Java and setting the basics, so I just have to provide with the data I want to submit and/or specific information?
REST API's are HTTP API's. The word REST is supposed to indicate something about how your API works. Basically that you use POST requests to update data and GET requests to retrieve it, and you have different HTTP endpoints for all of the different resources in your API, like Calls or Recordings.
The Twilio helper libraries (including the Java library) are basically wrappers around HTTP calls to the Twilio API. The idea was to make it easier for you to make API calls to Twilio by abstracting away the HTTP authentication and request stuff behind some more language-specific code. We also parse the HTTP response into an object for you.
I am making a automation website to send multiple files to an another site to prevent filling form every time to send a file.
I want to to make the POST request from server, because AJAX doesn't allow request to other domains.
How I can make this?
I am using Spring MVC3
Use apache http components - it allows you to perform http requests. You can also use (without 3rd party libraries) new URL(..).openConnection(), but it's less pleasant to code with it.
You can use Apache HTTP Components to implement pretty much any HTTP calls you want in your application. Also, note that it is possible to do cross domain AJAX with certain helper technologies like Flash ... if you really needed too.
What is the best way of save data using Restful web service without using Ajax? As a example I need to add a new Customer to the database using submit button.
What is the best way of transfer data format (text,json,xml) ?
How to read POST or GET data from HttpRequest object?
If you can please give me a example in java .
Thank you
I think you need to separate the concepts a bit. A "Restful Web Service" is a web service designed using REST principals, whereas AJAX is a set of technologies used often on the client side for asynchronous requests to multiple resources (without fully reloading the page). The web service really shouldn't care how the HTTP request is generated, just the contents of the HTTP request.
Now if you're concerned about writing a rest service in Java, I would highly recommend looking into JAX-RS and the reference implementation Jersey. There are lots of examples of how to get up and running. You can use MessageBodyReader implementations are to convert data from the HTTP request entity into Java objects.
Obviously this is not the only way to get started with writing a Restful web service in Java, but is one way.
It's very definitely worth your time to carefully study Richardson and Ruby's RESTful Web Services to learn the REST architectural style. In addition to #ach_l's recommendation to use Jersey, take a look at the Restlet Java framework, which is completely wonderful.