I will be developing a protocol that will encompass a client and a server module.
Several protocols that are close to the one I have in mind exist, but I want to make something simpler with less overhead and with something I have more control on.
The protocol I will be doing can and will be run almost in any scenario, local, web, lan, internet, etc. It can also run on a single box.
My question is, how can I start developing for the server side of the protocol?
Any ideas, insights, key words, starting points would be appreciated.
Regards
Do you want to develop the protocol yourself and then use it? or you are looking for a good protocol to use?
If second, I have recently worked with "Websocket" protocol which enables clients to communicate with each other via a server. It is a really good protocol and there are libraries in .NET ( >= 4.5), JAVA, Javascript, ... It is also supported in many browsers.
Related
Sorry for my ignorance , but this subject has been stressing me for days
I currently read in a book about networks that there is a UseNet that is like a blog , but uses a different protocol to communicate
My question is, when I'm developing a software, can I decide which application protocol will it work?
the TOR browser, I read that .onion sites use a different protocol than HTTP, how is this possible?
We first need to break up your question. There are protocols implemented in operating systems (low-level protos) and those implemented in applications (high-level protos).
What makes early high-level protos so interesting, like Usenet and SNMP, is that they are not dependent on low-level protocols. Basically they just need the operating system to provide a mechanism for streaming data to come to/from the machine they want to speak to. You can see that Usenet's protocol's , UUCP, code can handle TCP or serial connections.
My question is, when I'm developing a software, can I decide which application protocol will it work?
Yes, you ask the OS for your low-level protocol and you then implement your high level protocol in you application. You can also layer protocols ontop of one another.
the TOR browser, I read that .onion sites use a different protocol than HTTP, how is this possible?
While not a TOR expert, general proxy protocols like SOCKS, use TCP at a low level to connect to their first proxy and then using higher level protocols encrypt HTTP requests so they bounce around several proxies.
this is a very high level answer, you can absolutely implement a low-level protocol in an application. I am just speaking to the most common examples
I've recently decided to take on a pretty big software engineering project that will involve developing a client-server based application. My plan is to develop as many clients as possible: including native iPhone, Android and Blackberry Apps as well as a web-based app.
For my server I'm planning on using a VPS (possibly from slicehost.com) running a flavor of Linux with a MySQL database. My first question is what should be my strategy for clients to interface with the server. My ideas are:
HTTP-POST or GET based communication with a PHP script.
This is something I'm very familiar with - passing information to a PHP script from a form, working with it and returning output. I'm assuming I'd want to return output to clients as some sort of XML or JSON based string. I'm also assuming I'd want to create a well defined API for clients that want to interface with my server.
Socket based communication with either a PHP script, Java program, or C++ program
This I'm less familiar with. I've worked with basic tutorials on creating a script or simple application that creates a socket, listens for a connection and returns data. I'm assuming there is far less communication data-overhead with this method than an HTTP based method. My dream is for there to be A LOT of concurrent clients in use, all working with the server/database. I'm not sure if a simple HTTP/PHP script based communication design can scale effectively to meet the needs of many clients. Also, I may eventually want the capability of a Server-Push to clients triggered by various server events. I'm also unsure of what programming language is best suited for this. If efficiency is a big concern I'd imagine a PHP script might not be efficient enough?
Is there a commonly accepted way of doing this? For me this is an attempt to bridge a gap between some of my current skills. I have a lot of experience with PHP and interfacing with a MySQl database to serve dynamic web pages. I also have a lot of experience developing native iPhone applications (however none that have had any significant server-based communication). Also I've worked with Java/C++, and I've developed applications in both languages that have interfaced with MySQL.
I don't anticipate my clients sending/receiving a tremendous amount of data to/from a server. Something on par with a set of strings per a given client-side event.
Another question: Using a VPS - good idea? I obviously don't want to pay for a full-dedicated server (slicehost offers a VPS starting at ~ $20/month), and I'm assuming a VPS will be capable of meeting the requirements of a few initial clients. As more and more users begin to interface with my server, I'm assuming it will be possible to migrate to larger and larger 'slices' and possibly eventually moving to a full-dedicated server if necessary.
Thanks for the advice! :)
I'd say go with the simplicity of HTTP, at least until your needs outgrow its capabilities. (The more stateful your application needs to be, the less HTTP fits).
For low cost and scalability, you probably can't go wrong with a cloud like Rackspace's or Amazon's. But I'm just getting started with those, my servers have been VPSs from tektonic until now.
I'm looking to respond to an event from a web browser, hopefully any web browser. I'm working solely on windows and I came to the conclusion a custom protocol (I.E. myprot://collection/of/strings) is the best approach here (any objections?). But, handling an instance of this protocol seems to be a little less straight-forward. All I need is that collection of strings auto-magically passed to my already running application! (the app will only respond to these links while in a specific waiting state)
So answer me this, if you can, Whats the 'popular' method of handling them or better yet Whats the 'best' (subjective - I know) way to do it?
Although your answers don't need to be specific to my language, I am using Delphi for development.
Thanks!
Why not use the regular urls? http://localhost/myhandler/collection/of/strings. To the best of my knowledge custom protocols only work for IE and you still need to install the handler on the client computer.
In the past I used custom protocols in one of my projects to support laptops working offline, but it was back in the time when installing IIS on a laptop was a call for trouble. but now - what's the point?
Has anybody done or seen a deployment of Apache Thrift in an iPhone app?
I am wondering if is a reasonable solution for a high-volume, low(er)-latency network service for iPhones compared to HTTP.
One noteworthy thing I found is a bug report about running Thrift on the iPhone, which seems to have been fixed. But that doesn't necessarily indicate that it's a done deal.
Thrift and HTTP aren't mutually exclusive. In fact thrift now ships with an HTTP transport implementation to use. It's also a really nice way to auto-generate server/client code that avoids a lot of marshalling/unmarshalling boilerplate while still being really fast. Its internal representation is basically binary JSON, so it's very similar to a RESTful web service (except being easier to code and much, much faster).
So... anyone able to answer the original question? If not, I'll dive in myself with thrift's included Cocoa support and see how it works on the iphone.
Just my two cents..
The accepted answer to this question, is an opinion to not use a technology, not an answer of whether it is possible.
Thrift, is an interface definition language, IDL, like Protobuf and Capt'n'Proto. They permit the definition of a client/server/server protocol which is platform agnostic. JSON and Plist don't provide the same level of type conformance.
Having previously lead an iOS team with 10Ms MAU using Google Protobuf v2.5 on iOS, Android, Windows, and server teams, I can attest that IDLs are great on mobile. Apple uses them for syncing iWork content.
My current team uses Thrift for iOS and Android clients, with a mostly Scala backend. I much prefer it to Protobuf.
We send Thrift payloads over HTTPS and WebSockets. Once you have defined (in Thrift) your our wire communication protocol (i.e. frame structure), it's very easy to evolve your APIs.
However, on iOS in particular there are some implementation issues. The current version of the library is quite poorly packaged, and if you hope to make an Objective-C framework (e.g. for iOS 8+), then you will not be able to out of the box with v0.9.2. This is because the library headers include local imports, (#import "TProtocol.h" instead of #import <Thrift/TProtocol.h>) with no umbrella headers. Worst of all, the Objective-C compiler generates very messy Objective-C classes, also including local imports from the Thrift library.
Some of these issues are pretty damning. It indicates to me that while use of an IDL is very much a good engineering decision, not many iOS teams are using Thrift, unless they're huge with the resources to write their own library.
I've always disliked frameworks that use a common interface definition that builds out both server and client code. It keeps both sides too much in lockstep where in reality server API changes must be very flexible in the versions of clients that are communicating with it.
There are helpful libraries that make JSON or PLIST communication over HTTP pretty easy, and decades of debugging and understanding the HTTP protocol and how to use it well. I would ignore that at your peril.
I have used thrift's objective c bindings for a large iPhone app with a few million users. As one of the posters mentioned we can use Http which gets the best of both worlds. However there is no asynchronous HTTP client for thrift. We had to build an event based wrapper to allow non-blocking I/O calls. The underlying layer still issues one call at a time which hit us in a big way because we have one server call that takes a long time but it does not block UI flow and another really fast one that does block UI flow. If the underlying layer is busy with the slow command our fast command just has to wait. I am trying to build asyc http in c++ which can then be used on the iPhone but that is someways off from being ready.
Thrift as an external API doesn't make sense. Use it internally rock and roll.
I want to try developing an XMPP server component using XEP-0114: Jabber Component Protocol.
Which server do you recommend and why? I'm talking about ease of development, community support, documentation, examples, etc.
That's a hard question to answer, because I doubt there are many developers involved in developing across multiple XMPP projects and languages.
I can throw out a few personal perceptions but... I could be off-base!
What you're really looking for is which libraries would be recommended for component development. All the servers support the component protocol, so all you really need is a socket connection to the server and some helper routines to make the repetitive stuff like message parsing easier.
Where the server might matter is if you need tighter integration.
For example if you want your component to scale the same way as Ejabberd then you'll probably want to use exmpp.
If you need to deploy your component alongside Openfire into Java only enterprises, then you'll probably want to use smack.
If you are familiar with Python and want to prototype quickly use Wokkel.
I don't think documentation is going to be great for any of the libraries (haven't looked at them all though!) but that shouldn't be a huge burden. All you really need a good book on how the XMPP protocol works and then some sample code from the library and it's fairly easy to move on from there.
For an easy-to-use testing server I like openfire. Good instructions, easy to hook in components, and a good web interface for administration. Debugging is more of a "tail -f" on the logfiles, slightly java-ish.
I've used XCP professionally, but that's really for commercial use. It works well but if that's not your target deployment it's not worth the effort. I'm not sure if you can buy it separately any more.
I tried using ejabberd and I gave up quickly. I found the documentation for setup and administration awful. The config files are not self describing and there's no good walk through on the ejabberd site. It may be able to even fry my eggs in the morning for breakfast, but I couldn't get past install with the time I'd allotted to it.
For Openfire, there is something called Whack, which is a Java library for creating server components (XEP-0114).
Since the communication is over sockets, I presume the same code should work for any well designed XMPP server (such as ejabberd). However, I have only tested it with Openfire and it works quite well.