SharePoint Web Parts and SharePoint Web Services - web-services

I am looking at SharePoint web services and would like to know the best way to work with web parts. I have figured out most of the other stuff we will need but the functionality around web parts and the SharePoint Web Services seems complicated. So how do I
Retrieive a particular web part with HTML content? Is this possible?
Find out what web parts are on what pages?
I know that I can get the rendered html for an entire page through web services (although why that is exactly useful when you can retrieve the web page directly I'm not sure.) but would like to know if it is possible to embed web parts in external web sites through SharePoint Web Services.

"Web parts" are a means of "programming" Sharepoint. They are to Sharepoint much like "controls" are to Visual Basic, or "views" are to Android.
They're a creature of Sharepoint - I can't imagine you'd use them on an Apache server on a Linux host, for example.
Sharepoint web services, however, are intended to be a good way for Sharepoint to communicate with non-Microsoft technologies (like Java, for example).
If your "application" involves a heterogeneous mix of web servers and platforms, then Web Services is probably the way to go.
If your "application" resides exclusively on the Sharepoint server, and your "clients" just browse to it (preferably, browse to it with IE), then web parts might be a good choice.

Related

Discover SharePoint 2013 webservices

I'm struggling to access to some data hosted on a website.
I know this website was developed using Sharepoint 2013 (by someone else, and I don't have any contact with them).
I have the right credentials to the site, and via browser I can navigate and obtain the data I need (some electric measurements).
I need a way to obtain the data using a webservice.
Is there a way to discover all the webservices implemented on the site? And to gain access to those data?
I browsed the lists on _api/Web/Lists but due to my lack of knowledge I didn't find anything useful.
Thank you all!
Best way to start you discovery of default SharePoint web services is from here
There are at least 3 default services that you could use to get more information from different lists and webs:
/_api/site
/_api/web
/_api/web/lists/getbytitle('listname')/items
Unfortunately I don't think there is a way to discover all web services there are on your particular site

Web application as a client for web service

I am new to Web development. And hence, if the question is dumb, please be polite. For creating my application, I had to take a decision of whether writing a web service or a web application. After searching a few questions in stackoverflow, I came to know that, web service is something which doesn't involve human interaction. And web application is what human uses ( the UI/web page kind of stuffs ).
But lately, I saw gmail is a web service ( email service ). But I was confused from here on, because, gmail provides a UI, and human interactions do occur. And from there on, I got confused again.
So what I figured out from this is, gmail website is like a web application for users to use directly. The web application in turn uses the web service provided by Google for email. Is my understanding right? So can a web application be a client for web service?
If I am wrong somewhere, please do correct me. I hope to be clear after someone throws light on this with some good example. Thanks in advance.
You are quite right. Basically a Web Service has several endpoints over HTTP (normally) that provides data (generally in JSON or XML) and are meant to be consumed by Web Clients. Sometimes the are also called Web API's (Application Program Interface).
A Web Application is quite similar to a Web Service but it provides an interface where the user can interact with. Usually Web Applications are consumers of Web Services or Web APIs.
Following your example, Google email is could be considered as both, a Web Service and a Web Application. It is a Web Service because it provides a set of HTTP endpoints that works independently of its Web UI Application (GMail). In fact, you can find third party Web Apps that interact with the Google email Web API.
This concept is very important when designing Web Solutions. Ideally you want to design and implement a good Web API, usually a RESTful Service (in JSON/XML). Then you or others will be able to implement different types of applications (Web, Mobile, etc.) because of this API.

Difference between portlet and a webservice

I am not sure if I am comparing onion with a cabbage. But I am really confused with the portlet and a web service. I know that web service is making your software components in your application as a service to other applications but to me it is similar to a portlet responding to requests. I know that my understanding is making you(Portlet & SAAS developers) really upset. But I need some clarity on this.
Why cannot I use the request-response to portlet work similar to a web service?
If yes, what is the benefit I get in using a web service than a portlet?
If not, then what are portlets lacking to act as a web service?
I am a newbie in portlet development. Please dont curse me for this question.
Please suggest.
EDIT:
Most of the answer say that the portlet is a UI component. My customer has requested me to create a webservice in liferay. So is it to make a portlet as a web service? If yes, can you please provide a pointer or some code snippet?
Addressing your 'edit' specifically with regards to Liferay...
Liferay plugin projects can expose web services without too much work.
The Liferay Service Builder actually has facilities so you can create SOAP web services or JSON web services backed by tables in the Liferay database (and that make queries on existing database tables). In the case of JSON web services, the URL scheme generated is not RESTful (unfortunately), but it is well defined. With a bit of work on your part you can impose Liferay's permission system on web service calls as well.
Here's a reasonable starting point in the Liferay Developer's Guide:
See the links on that page to SOAP and JSON services.
Note that a 'portlet' is only one type of Liferay plugin. The web service facility is part of the service layer - which can be used by many plugin types. So there isn't necessarily a portlet involved in creating a web service in Liferay, you can make a web service that has no visual component associated with it.
Portlets are areas you create to add and display content. Portlets can be added to the left and right of the center body area and can contain myriad content ranging from news, events, calendars, RSS feeds, collections, plain text, and more. Also, you can set properties and policies for showing the portlets.
you want to use portlet when
You have content you want to have special focus, like news.
You need to specify the configuration data for an item. - i.e. number of entries to show.
You want to give the content editors a choice about when and where to display content.
You'd like to show it only to some groups or users.
On the other hand, web services:
Enables applications to expose their services
“progammatically”, i.e. the services can be invoked by programs
Enables software running on other computers (could be a desktop, mobile phone, PDA, etc.) to invoke operations exposed by Web applications
if you are trying to identify the main difference portal historically, the portlets have three layers architechture (client, middle tier, backend) this cause two weakness:
Different portal groups have no well established way of sharing services
Different technologies(Java, Perl, CORBA, EJB) in middle tier.
Different protocols(GRAM, IIOP,...)
Consequently, lots of redundancy, reinvention
Example: batch script generation
so Web services address the service sharing problem and reduces the redundancy.
source1 source2 source3
Portlets are meant to be a user interface component in a portal solution.
Web Services provide functionality to remotely interact with a system commonly using SOAP, REST, JMS or other related
They provide completely separate functions. The closest you get is the serveResource method in portlets. This functionality is used to serve various types of content from a portlet (such as a PDF document or an AJAX response) without the need to perform a full page request.

Do I need a web service in this case? When do we use them?

my issue is about web services and all the stuff around that. I've developed a java web app, using hibernate (to connect with a mysql DB), jsf and primefaces. The only thing I have to show to the user is the index.xhtml which will search a data in a database. All of this is running on my PC with my local apache server.
But a doubt comes to my mind when I wonder if I deploy this web app in the apache server of the company, do we need something such as a web service o something like that o they just can access to the index.xhtml and start the queries?
Sorry for this but I'm totally new repesct web services, web app, web server and all these stuff.
PS. So, when do we use web services? and web server?
Thanks in advance :)
A web service is typically used as an API that might be integrated into another application. For example, if you have a way to accept payment information. You could make that a web service that would let some other application (e.g. an auction site) make calls into your web service to do some work.
Think of it a bit like a DLL that is accessible on the web. It won't have an interface, it is a collection of methods that either return data or execute some code. It will not return a UI.
So when you use a web service would be a similar question to when you need to break code out into a separate assembly.
On your specific question above, you would not need a web service, if your web application is doing everything you need it to do, then all you need is a web application.

What is web-service and how to develop it

I am looking for some good starting point for developing web-service.
I have one application which has C++ library support using which I can get all the details of the product.
I am supposed to write web service SDK for the same.
Any help.
Web services generally refer to a technique that allows code to be called via HTTP requests and responses. This is similar to a web page, except that what is returned from a web service is usually not HTML intended to be displayed in a browser - it is usually data of some kind.
"Web Service" is one of those terms that means whatever the person saying it means. Basically, its just a way to access data or functionality via http. There's a few standardized methods - REST, SOAP for web services, or you can just serve up XML, JSON, or other data from a plain old server side web app.
What you'd want to do is investigate what form this Web Server you are supposed to write needs to be in (SOAP, REST, something else), and then go from there.