We have an iPhone application created by an external consultancy that we're planning to add card payment facilities to in a subsequent release.
We plan to host a service ourselves in order to process the payment stuff, with SSL encryption. We have in-house expertese for all of this apart from the (contracted out) iPhone bit.
Are there any specific gotchas that we should be aware of that concern designing web services for iPhones?
We'll be writing the web service in C# 3.5.
JSON data format is better to be converted into NSArray or NSDictionary objects. It's easier and faster to be parsed.
So, specifically for the iPhone, it's a lot better to consume JSON data. Unless if there's some technical complexity that JSON is unable to handle.
Check YAJL:
http://github.com/lloyd/yajl
There are Objective-C wrapper/implementations by gabriel in github and by MGTwitterEngine.
TouchJSON is another code that's simpler than yajl. You can convert JSON string into NSDictionary or NSArray object in 2 lines of code. But, it maybe slower.
I'm not sure there are really any special considerations. The iPhone should be able to communicate with most types of webservice.
I worked on an iPhone app that communicated to a RESTful webservice written in Java.
I imagine it's pretty straightforward across the board - there are plenty of libraries for parsing/generating XML or JSON formatted messages, the iPhone can handle HTTP authentication, HTTPS, caching, etc.
It's just down to your iPhone developer to get it right :)
For SOAP based web services I strongly suggest that you try gSOAP. This library does not support Objective-C, however it supports C and C++ and is certainly the most complete open source project to access SOAP based web service; it also outperforms all of the other libraries.
For Objective-C you may want to try wsdl2objc, but I am not sure if it provides support for SSL/TLS (gSOAP does).
Finally, REST based web services are easily handled using ASIHTTPRequest.
Related
We have a web-based BI reporting product. We have exposed certain webservices which mainly return html content and do authentication.
We are in a initial process of developing an iPhone App, which will interact with these services and get data on iPhone.
There are couple of things we need to make sure before we start with the actual development process...
1) Should we use SOAP or REST (Will have to write the server part in Java) for the communication between iPhone and our web-application?
2) If we use SOAP, Can you suggest something, which will effectively create web services stubs in Objective-C.
3) In either case (SOAP or REST), what security mechanism is suggested by Apple?
We want to know your thoughts on the best and effective way communication could be done between iPhone app and backend servers (mostly written in Java)
Thanks in advance.
If it is an option, I'd use REST
Never did it, but may this will help: http://abhicodehelp.blogspot.com/2010/12/handling-soap-with-iphone.html
I'd do any HTTP-Communication using ASIHttpRequest. It is SSL-capable
In my apps I use simple URL requests returning XML / Cocoa-touch plists over https. I guess that's called "REST" -- it's simple and quick to implement. There are long flame-fests over SOAP vs. REST -- I just use this technique and get my apps done :)
I would like to build an XML over HTTP provisioning interface using Zend Framework. Should Zend_XmlRpc_Server be used for this purpose? If so, can you recommend any guides on using it? (Specifically the part retrieving incoming XML and parsing it.)
What kind of service is it? - will you send binary data or rather short texts? Will all clients be in PHP mostly or you are foreseeing a wide range of clients?
Usually if you're doing a web-based small service, REST will do the trick, it's easy to develop and consume, even by plain JS frontends, such as jQuery.
If it's something more complex, you can't go wrong with SOAP, though it's a bit complex in developing. Make sure you arm yourself with SoapUI
XmlRPC has some limitations, especially sending binary data. There's some thorough comparison to have a look at this blog
I do not have much experience coding systems dealing with web-services. Please help me in solving following confusion.
One of my clients want me to build an iPhone App that had native UI controls but deals extensively with Web Services. Right from authenticating the user into a network to loading a list of users or anything related in the app will need to talk to a web service.
They have web services deployed on .NET on the server side and already have required data in SOAP web service. By doing some basic research on the web it seems that dealing with SOAP from an iPhone app could be messy and affect performance.
The client is ready to make the data available in from of JSON or plain XML data. I am not sure which one would be a better option? The data could range from few tens to few hundreds of rows only.
Can someone please point me how can I do a comparative study in short period of time (3-4 days) even if it takes for me to learn about the SOAP, XML, JSON and REST web services. Is this even possible or should I just go with some expert advice? - Waiting for expert advice :)
Thanks
XML and JSON are data interchange formats. JSON is generally considered easier to work with, although a good library should make both palatable.
REST is an architectural style; it is the architectural style that HTTP is designed to support.
SOAP is a protocol for implementing web services, and it does not follow the REST architectural style; it's more of an Remote Procedure Call style.
I dislike SOAP because it forces you to rely on tools to manage many of its facets. If your tools happen to work differently than the tools used by the other end, then it becomes extremely painful.
I recommend reading RESTful Web Services for a general overview of REST, and why it's "better" than SOAP.
I don't have any good resources for SOAP, or anything iPhone specific.
RESTFul webservices can return responses in XML or in JSon, the option of using such service is better than soap for iphone because of the overhead involved with soap as you mentioned. Basically when u get responses in xml or json its just some text that you need to parse. I would recommend going with Json as there are json parser libraries for iphone out there already and its very simple to use...Here is a tutorial for using the json parser and parsing your responses, Json tutorial...hope it helps
We are going to set up a solution where the iPhone is requesting data from the server. We have the option to decide what kind of solution to put in place and we are not sure about which way to go.
Regarding SOAP I think I have the answer, there are no really stable solution for doing this (I know there are solutions, but I want something stable).
How about REST?
Or is it better to just create our own XML? It's not going to be so complicated reguest/respons-flow.
Thanks in advance!
I've created an open source application for iPhone OS 3.0 that shows how to use REST & SOAP services in iPhone application, using XML (using 8 different iPhone libraries), SOAP, JSON (using SBJSON and TouchJSON), YAML, Protocol Buffers (Google serialization format) and even CSV from a PHP sample app (included in the project).
http://github.com/akosma/iPhoneWebServicesClient
The project is modular enough to support many other formats and libraries in the future.
The following presentation in SlideShare shows my findings in terms of performance, ease of implementation and payload characteristics:
http://www.slideshare.net/akosma/web-services-3439269
Basically I've found, in my tests, that Binary Plists + REST + JSON and XML + the TBXML library are the "best" options (meaning: ease of implementation + speed of deserialization + lowest payload size).
In the Github project there's a "results" folder, with an Excel sheet summarizing the findings (and with all the raw data, too). You can launch the tests yourself, too, in 3G or wifi, and then have the results mailed to yourself for comparison and study.
Hope it helps!
REST is the way to go. There are SOAP solutions, but given that all people end up doing with SOAP can be done with RESTful services anyway, there's simply no need for the overhead (SOAP calls wrap XML for data inside of an XML envelope which must also be parsed).
The thing that makes REST as an approach great is that it makes full use of the HTTP protocol, not just for fetching data but also posting (creating) or deleting things too. HTTP has standard messages defined for problems with all those things, and a decent authentication model to boot.
Since REST is just HTTP calls, you can choose what method of data transfer best meets your needs. You could send/receive XML if you like, though JSON is easier to parse and is smaller to send. Plists are another popular format since you can send richer datatypes across and it's slightly more structured than JSON, although from the server side you generally have to find libraries to create it.
Many people use JSON but beware that it's very finicky about parsing - mess up a character at the start of a line, or accidentally get strings in there without escaping "'" characters and there can be issues.
XML Property-lists (plist) are also a common way to serialize data in Cocoa. It is also trivial to generate from other languages and some good libraries exist out there.
You are not saying how complex your data structures are and if you actually need state handling.
If you want to keep your network traffic to a minimum, while still keeping some of the structured features of XML, you might have a look at JSON. It is a very light weight data encapsulation framework.
There are some implementations available for iPhone, for instance TouchJSON
Claus
I would go with simple HTTP. NSURLConnection in the Cocoa libraries make this pretty simple. Google Toolbox for Mac also has several classes to help parsing URL-encoded data.
I think it's obvious that REST is the new king of servers communication, you should definitely use REST, the questions should be what REST methodology you should use and what coding language, in my post I present few very simple implementations for REST servers in C#, PHP, Java and node.js.
I've started my degree project, a mobile application suitable for iPhone, Android and (in the near future) Symbian. The server architecture is the following:
web site (for "standard" users);
web service (for mobile connections), based on TomCat and Axis2;
mySQL DB to storage users data.
Surfing across the web, I've read a lot of discussion about the interaction between the iPhone and Web Services, and I've to say that I've not a clear idea of what I can do and what not.
Let's start from the protocol used to retrieve data from the DB: the Android-side application uses SOAP protocol, can I do the same with iPhone? Are there some limitations or problems?
I have also read about the using of REST instead of SOAP, could it be possible with the server architecture described above? Which are the main advantages/disadvantages?
Sorry if these questions sound "n00b", but it's my first real experience with iPhone and the lot of informations found on the web messed up my mind and I'm scared to be confused. Forgive me for any error.
SOAP is simply too heavy for mobile communications. Why do all the work to wrap requests in an additional XML layer you'll have to parse? You send more data than you need to, and impose greater CPU burden on client and server.
Use REST. If you are doing a cross-platform project JSON makes a great payload container, otherwise plists work well for sending data from the server.
You can definitely do SOAP on the iPhone. Here is a nice tutorial on the subject. After all, SOAP is a HTTP based protocol and you have all the libraries you need to do HTTP on the iPhone.
Having said that, RESTful APIs are simpler than SOAP, so you might want to consider them. They're also HTTP based so you won't have any problems on doing that on iPhone. On the server side, if you use Java, you will have to use JAX-RS to implement that part.
Hope it helps.
Google Buffers
If your looking for a language and platform agnostic solution have a look at Google Buffers. You can easily serialise objects for transmission over the wire.
This question should get you started in Objective-C.
JSON
I have also used JSON within iPhone Apps with great success. Again, relatively language and platform agnostic but much simpler than Google Buffers.
SOAP with Fast Infoset is suited for small devices:
JAX-WS 2.0 and its reference implementation support both Fast Infoset and MTOM/XOP. This article includes information about Web Service Performance for Fast Infoset vs. MTOM/XOP:
http://www.devx.com/xml/Article/35385/1954
Fast Infoset is optimized for small
devices that have bandwidth
constraints, and is supported by many
vendors such as Microsoft .NET and
.NET CF, Sun GlassFish, BEA WebLogic,
IBM SDK for Java 6.0 and others.
http://en.wikipedia.org/wiki/Fast_Infoset