I'm a hobby programmer trying to build a client/server application suite, using Delphi XE.
I write stand-alone applications occasionally, for my personal use. The problem is I don't know ANYTHING when it comes to networking / multi-tier. I am willing to learn though.
I looked for ways to do this and DataSnap and IntraWeb jump out as the most likely candidates for the job. But, before I start using one or the other, I would like to know a few info I wasn't able to find on the web:
If I build an IW stand-alone app and deploy it on my site (as server) will I be able to connect to it/retrieve data with a client application? I need to do that within my Delphi written app, without using a browser and without using HTML (I know very little HTML and I'm not eager to learn). I know IntraWeb isn't meant for this, but will it work?
If I go with DataSnap and build a server app, will I be able to deploy it to my website? Or do I have to make a computer on the network the server?
In case anyone wants to know, I want to connect 5 computers(from different cities), to exchange information between them, if at all possible using ADO, as I'm very familiar with it.
Intraweb is a server based tool for building web sites, accessed via a browser. It is not "proper" multi-tier, and it sounds like it isn't what you need.
DataSnap is designed to do what you want I think. First, the ADO part would be on the server, and you would define an interface that the server offers to do tasks. Then your clients would call that interface over the internet to get data or do those tasks etc.
As for whether they will work on your web server, that depends on what your server is, and the access that is provided to it. A web server is just a PC, but typical hosting is fairly restricted to running "scripted" languages on that server, which reside in the hosting directory. A Delphi server would be a running executable (usually a Windows Service), listening on a port, and needs much more access to the computer than typical. You would need at least a virtual Windows server with administrator access to the desktop to allow it to work. In the first instance though, you could happily run the server on a DSL line or similar and make it work just fine. You can worry about hosting it on the net when you have customers paying for it.
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I have build a few apps that receive and send data over a Datasnap server.
I have multiple Datasnap servers running on my customers servers.
The Datasnap server runs as a Windows Service on their machines.
How can I remotely update those servers or what is the best way to do this?
Is it maybe better to make the Datasnap Server run on IIS instead of as a Windows Service?
Can I let the server update itself? Maybe if I make a function that sends the new version of it that it can replace itself?
I can see no way of updating the exes on your customers' machines without a) getting them to do it; b) logging in remotely using something like VNC (though I'd be happy to know of a better way).
This is an approach I would consider:
I would look to have a separate application which is called by the service on a regular basis (daily/weekly) that looks for a new versions of software on your server (or somewhere), downloads it stops the service, replaces the service's exe and restarts the service.
In the new service exe I would have something that calls this application periodically, so you only have to do this once.
This assumes the machines that run your software have internet access.
Don't forget to include a mechanism to update the updater application.
I need the VPS services for hosting my ASP.NET project.
However, it's not just asp.net hosting, I also need SQL Server, RabbitMq and either my running conrole app or my windows service.
So I read the suggestions to use Amazon Web Services as they provide first year for free.
However when I registered I found that I don't have a clue of where I am:
I don't see the option of creating a virtual machine with Windows
I don't see the option of setting up SQL Server on such the machine
and so on.
So I was wondering whether I'm in the right place?
Please advise if AWS can provide me with what I need or I came to the wrong place?
AWS can provide all that you listed, but you'll need to do some learning on your end.
Basically you create an EC2 instance, and then use RDP to remote into it, and you can install software and configure it to your hearts content - just like it was any other physical server.
If you want to use SQL Server, you'll have the choice of installing it directly on the instance using your own license, or using their 'hosted' version of SQL Server call RDS. You'll need to read about it and decide which option is better for your project - there is no single right way.
Lastly, I will point out that although the 'free-tier' is nice, except for a really small application (i.e. small db on a low traffic website), you may find out the 'free-tier' does not quite give you all the power you need to run a busy application. I would not base your decision on wether or not you should use AWS on how much 'free' stuff you can get. The free-tier is nice for learning, but plan on spending some money for a truly robust solution.
I am working on a c++/cli program that which records live video (I use OpenCV). Now I need to facilitate it with broadcast support where other people can watch it by using their web browser. As you know videos are sequence of images so I need the web page to get the new "frame" grabbed from the web cam and display it in web page in speed of 5 times in every 1 second (5fps). For this, in order to allow others to access the web page, I need a web server (running in localhost is OK because connected machines can access it).
I am not up to web technologies so I have only used Apache Tomcat and Microsoft default server.But in both, you have to setup the server, upload the files to it and much more. But there are some programs like this and this where they do not require such servers where you need to install and setup but still does the job. I think they are using embedded web servers.
So, are there are any servers like that which matches to my requirements? Please note my program is in c++/cli and I need to distribute the server with it as well, just like the above 2 programs do.
Edit
Please note that I mentioned C++ / CLI just to give you a clear understanding about my system and not because I am seeking for a server with CGI script support or I m seeking for a server built with c++. If at least JavaScript can run there that is enough because I can update using it.
I'm planning on writing a control panel for Minecraft in Rails but I don't have much experience with Java at all, Minecraft seems to have some standard remote connection and query tools, but most conventional panels don't seem to use them. For example with McMyAdmin, I have disabled remote connectiona and the query, but it still seems to be able to communicate with the server after restarting it after I've edited the server configs to disable the settings.
What I'm asking is if anyone knows how McMyAdmin communicates with the Minecraft server, it comes with a plugin, but I've deleted that as well and it still seems to be able to communicate with the server, I know McMyAdmin is written in .NET and I believe it uses Mono as it's server, as it's cross platform.
If anybody could shed some light on this I'd be ever so greatful, just trying to get my head around the communication.
McMyAdmin uses the plugin to open a socket that it can interact with(Not sure which features are provided using this plugin). The rest of the features are just from the Process instance that it creates. It also just edits the config files for a few things as well or runs commands using the input stream of the process.
I am a seasoned Delphi developer and would like to create something like seamless terminal services where an application is executed on a server but appears on the the desktop of the client.
To someone working on the server I don't want them to see the remote application running (except if they looked in at the list of running processes).
I'm lost as to how to go about this, where to start, how to get an application to render to a surface other than the servers desktop.
Starting from 2008 Terminal Services (which has been rebranded to Remote Desktop Services) offers RemoteApps which do exactly what you describe. Citrix (XenApp) can do this on all windows (server) versions. So you might want to look at those products before deciding to recreate them yourself.
If you do decide to go on, this link might be interesting, it's a sample project called "Extending Microsoft's Terminal Services Client To Provide Seamless Windows"
From what you are describing, I'd say you should be looking at writing a windows service (not terminal services) and using a inter-process-communications (IPC) system to get status information to a "client" application that can be run by the appropriate user, either on the same machine or another over the network.
Myself, I do exactly this using the RemObjects SDK which makes my client application look like it is just making function calls, but actually they go to the server which implements them. The server can then get on with its job in one (or more) thread, and all the user interface is done in the client which finds out what to display using the IPC channel.