Sandbox architecture in ASP.NET? - asp.net

Is it possible to develop a web-app in ASP.NET (framework is not a constraint), to have a sandbox architecture, and deploy widgets without disturbing the parent application?
I expect both the parent application and the widget to be developed using .NET.
EDIT:
To elaborate, I want to have an web-app, say App1, and widgets (say wid1 and wid2). wid1 and wid2 should be like a plugin into App1, only difference is that, if I make any changes to wid1, I want to be able to deploy it without disturbing App1 or Wid2.
The widgets can be something similar to a flash object, only that it needs to be developed on .net.

Would something like the Managed Extensibility Framework be what you are looking for? They even have a WebForms sample:- http://mef.codeplex.com/releases/view/44166

I believe you will want to look into Application Pools.
In a web server running IIS with ASP.NET websites, you can create Application Pools which will contain your applications (web sites). You can restrict pools to limit resources usage like RAM, CPU, # of threads, etc. If one of the websites go crazy, it should only affect it's own Application Pool. You can put more than one website in a single Application Pool so if you put all of the websites in one Application Pool, then they will all crash together.

Related

WinForms Server To Handle ASP.NET Web

I am about to convert my Winforms applications to an ASP.NET Web Application. The only question I have is the following:
My Winforms application connects to a server via TCP/IP connection (TCPClient), and handles all requests and commands through my own custom protocols (Strings sent that are validated server side and sent back to client)
Can I keep this same Server to handle the requests from my ASP.Net Web Application (I plan on using the same protocol)?
Will there be anything I have to change within the server? How different is migrating a Winforms application to an ASP.Net application?
Do you suggest I use WebForms or MVC?
Well, we might be confusing things here some what.
You have a asp.net application. Then the question is:
asp.net webforms application
or
asp.net webform web site
While both above are similar?
Well, in the first case, a web application means that you compile your code BEFORE web deploy, and for the most part this site is to be considered the WHOLE site (the web config file is in root etc.). And any external assemblies etc. are linked at compile (or publish time). And you are as a general rule NOT EDITING and design and working against the actual web site files. In other words, the folder that holds your project CAN NOT JUST be dragged say to a web server folder and it will work.
And of course this allows you to write custom handlers for pdf files or whatever.
So you can add + hook into the http handlers.
And of course this also allows you to build say a custom logon (authentication provider).
So, you can think of a web application more like a WHOLE application - just like say all the truckloads of source files that you have for a desktop application. You THEN compile this whole big thing, and you compile down to that .exe (or .dll).
You THEN must web publish the whole thing as a application to the web server.
so this is the whole site. Things like custom logon providers, http handlers, and even trapping the Session() start can be done.
And When you web publish, then you get a standard web site, and folders and all of the SOURCE vb.net (or c#) files are removed. Just like compiling down and deploying any desktop application - the source code and files are REMOVED. Needless to say, this approach is "common" to developers coming from a desktop environment.
So no sub-sites really can be done with this model. You are hooking DIRECTLY into the IIS web server.
A web site?
That is ONLY a set of folders that you can have the IIS site work against. In fact one could argue that AFTER you publish a web application, you get "mostly" the SAME thing as a web site.
But this model with any ease cobble up a web site with say 5 pages and JUST deploy that to your local web hosting? Nope!!! - can't do that!
The reason of course is you NOT dealing with ready made web site layouts and files. You HAVE to compile the whole mess into a application.
So like deploying an desktop application you are deploying a WHOLE system.
Now, if you going to have a site with say user logons, passwords and write a custom authenticaiton provider that IIS will respect and use? Again a web site can't do that.
So again you need a code system that supports logon hooks, and lets you control what those people can see and do. So for a line of business application? Well that quite much going to be a whole system - and thus you need control of logons, a master page(s) etc.
So the root, the config files, how they EVEN logon to your site? Everything must be just right and that config setup and file is the BASE SITE configuration for the web server. You can change authnetical providers - include custom http handles etc.
So this is a whole custom site here. And as noted, this is publish type operations.
However, asp.net for a long time ALSO supports what is called a web site.
So when the web started? Well, you just dumped web pages into some folders - maybe some hyper links to jump around. But a LOT of developers started out working this way. And because you can DIRECT edit the files and save them back to the site? Then no real concept of a application compile or even a web publish exists in this context. It just files sitting in a web ready format and a simple set of folders.
So a asp.net web site = just folders and files - no publish.
Now for one small change, no question that a web site is nice. And BETTER is that you can say take a set of folders and just DROP them into a existing web site - your not really publishing anything, so like the old days, you just edit and copy files to the web server folders and they work. This of course common fair html files.
But IIS does support using aspx pages (files) this way also!
Since this is just SOME folders with web pages? Then you can create and build say a bunch of different folders - each having their own cute little mini-web site. And this means that publishing to your cheap $8 per month asp.net hosting is possbile. You don't need a full IIS server and the ability to manage the IIS server system. All you EVER do is just copy files to the web site. Nothing more, nothing less. As a result, you don't have use of Session() start, and even the logon events are not under your control (unless of course you rolled your own and don't use IIS security.
With simple files and folders? Then your $8 hosting site can be used.
However, all if not most low cost simple hosting sites don't support asp.net applications.
So you can think of a web publish as replacing your base web application system the hosting provider gives to you. it also why you do NOT get use of the full ASP.net and IIS configuration options for the web site (your web provider controls and has that!!!).
One huge benefit of web sites is ease of change. As noted, you can point VS to directly edit even on the live web site files!!! There is really not concept of publishing - you just editing files and saving them to the web site folder. And this is really nice for a small change - the web site will re-compile the code for you, and for a large site, you can make a change to one wee bit of code behind and the web page - just copy that page and code to the site and you are DONE!!!
With a web application? you are doing a full-re compile, re-publish to the site for ANY and all changes. (well, ok, you could sneak in and say edit/change some markup on web page, but for the most part anything that messes with controls on a page would and could very easy break the compiled .dll's that are driving that page.
do you suggest I use WebForms or MVC?
That is a huge deal. MVC does not even have a visual designer for your web pages (you can only see and write markup).
And the whole MVC code model and whole event model is VERY different. So perhaps while a great idea to adopt MVC? (it is!!), it is darn near a whole re-write of your existing site - they work very different from asp.net webforms applications.
to a server via TCP/IP connection (TCPClient), and handles all requests and commands through my own custom protocols
If you mean custom http handlers? No, web sites don't' support this, you have to be creating a web site application. You can't by a simple act of placing some web pages on a web site have the lower level http handlers and network stuff change - you can only do that with a web application. Same goes for the authentication provider(s) you choose - simple web sites don't allow you to build your own custom providers (but you can roll your own logon system from scratch - but you not then enjoy even simple setups that automatic secure web pages based on their memberships in given security roles.

ASP.NET Core Web API living inside a ASP.NET 4 IIS Web Site

I am tasked to to build a Web API application. The app will be hosted inside an existing web site - a pre-ASP.NET 5 web application with a WCF web service.
I wonder - can I build the web-api application using ASP.NET Core 1 in a way that it can happily exists as a sub application inside the already existing site in IIS?
Thanks!
Yes, this is possible, I'm doing the opposite of this scenario but conceptually its the same thing. You need to create your subsite as a separate application in IIS with its own app pool. That app pool needs to be configured No Managed Code per the instructions on the Docs site https://docs.asp.net/en/latest/publishing/iis.html
The only other thing you need to watch out for is that the web.config in the subsite will inherit some settings from the root web.config, so you need to remove or clear things sometimes like handlers, modules, etc.
If I understand you correctly it is not possible what you want. Please refer to the following documentation about hosting ASP.NET Core on IIS: https://docs.asp.net/en/latest/publishing/iis.html.
If you specifically look at the .NET CLR version in the application pool it should be "No Managed Code" while your current website is set to a .NET framework version I assume. This is because ASP.NET Core is now cross plaform and completely web server agnostic. It even needs a little 'trick' (the ASP.NET Core Module) to work on IIS. See: "The module creates the reverse-proxy between IIS and the Kestrel server."
But if you follow the link provided above I think you'll manage to work it out.

How can I change a single aspx page from hosted published website?

I have made some edits in my aspx code behind cs file. I can't make the site down since our site will miss our viewers.I want to make the update possible with this single page upload.
You are searching for strategies of seamless deployment for IIS asp.net apps; this can be achieved via two machines and a load-balancer before them - Seamless deployment in ASP.NET (IIS kills worker process before new worker process is ready)
Another convoluted way is to host two identical websites on the same host and switch between them, as explained - Is smooth deployment possible with componentized ASP.NET MVC apps?

ASP.NET warmup/initialize

I'm trying to eliminate (or at least minimize) startup/warmup times for my .NET applications. I'm not really sure on how to do this even though it's a common concern.
There's a ton of questions about slow startup of .NET applications. These are easily explained by pool recycles, worker process startup, dynamic compilation of .aspx files, JIT etc. In addition, there are more things that may need to be initialized within the application such as EntityFramework and application caches.
I've found alot of different solutions such as:
ASP.NET Precompilation
IIS 8 Application Initialization (and for IIS 7.5)
Auto-Start ASP.NET Applications
However, I'm not entirely satisfied with any of the solutions above. Furthermore I'm deploying my applications to Azure Websites (in most cases) so I have limited access to the IIS.
I know that there are some custom "warmup scripts" that uses various methods for sending requests to the application (e.g. wget/curl). My idea is to create a "Warmup.aspx" page in each of my ASP.NET applications. Then I have a warmup service that sends an HTTP GET to the Warmup.aspx of each site every ... 5 minutes. This service could be a WorkerRole in Azure or a Windows Service in an on-premise installation. Warmup.aspx will will then do the following:
Send an HTTP GET to each .aspx-file within the application (to
dynamically compile the page)
This could be avoided by precompiling the .aspx pages using aspnet_compiler.exe
Send a query to the database to
initialize EntityFramework
Initialize application caches etc
So, my final question is whether there are better alternatives than my "Warmup.aspx" script? And is it a good approach or do you recommend some other method? I would really like some official method that would handle the above criteria.
Any and all suggestions are welcome, thanks!
Did you try this IIS Auto-Start feature described here ?
https://www.simple-talk.com/blogs/2013/03/05/speeding-up-your-application-with-the-iis-auto-start-feature/
You could have two instances of the site. When you need to deploy a new version, and therefore suffer a startup cycle, remove one instance out of load balancer rotation, deploy and start it, set it in and do the same for instance 2. A rolling deployment.

Can I convert a non-MVC asp.net application to be Azure compatible?

Can I convert a non-MVC asp.net application to be Azure compatible ? Or If i want to create an Azure web application, should it be MVC one ?
The other answers answered your question about converting your app to MVC for deployment to Azure (you don't need to).
If you're creating a new web application and go with ASP.NET MVC (which I'd recommend), just remember if you go with MVC3, you may have to make some of the MVC3 DLL's CopyLocal for your deployment, as it won't be part of your web role instance. At least that's how I still understand it. The 1.4 SDK of the Azure SDK doesn't have a MVC3 Web Role template yet.
See this post on steps to get your MVC3 app Azure-ready.
Hope this helps.
You may take a look at the following blog post for migrating an existing ASP.NET application to Azure. It should not necessarily be an ASP.NET MVC application. Any ASP.NET application will work.
azure has 2 roles
1. a webrole
2. worker role
web role is nothing but an asp.net app. so no need to convert it into an MVC app just any asp.net thing will do fine
Yes, you can. But you need to be aware of certain limitations too, none of which were mentioned in the answers already given:
Your application should be stateless, unless you are running a single instance (for most apps 99,9% reliability is OK, but there are some where you want 99,95%, so you need at least two instances + it gives you additional benefits of a load balancer, etc.). The reason for this is that if you have more than one instance, the load balancer will deliver the request to a different instance. You can use AppFabric Cache to solve this.
You don't have a file system - this is not entirely true, but in reality you should never rely on having local files. All you image uploads (e.g. user profile pictures) should be uploaded to a blob storage and linked to there. How you do this is another matter, and one that can be approached differently depending on the architecture of your existing application. You can get away with files, by using Azure Drive, but it's slow as hell.
No Event Log / RDP - this is also only partially true, but you should rely on other ways of getting diagnostics information from your role. While you can RDP to your role instance, there are better ways (e.g. Azure Diagnostics storage).
Database should be chosen carefully. Sure, you have SQL Azure available, but it's expensive (1 GB = 10 USD/ month). If you can get away with stuff like Table Storage, you may save on some costs. Again, this depends a lot on the architecture.
As for the second part of your answer. MVC as a pattern is nice. It saves you a lot of time, it's much more adapt for the Web as WebForms ever will be. The event based system was designed for Desktop applications, and it was forced onto the web. However, going to Azure does not imply a requirement to go to MVC. What I suggest you do however, is treat it as a nice jump-start opportunity to look into MVC and see how it could help you write your apps better & faster.
As with any other case involving architecture of apps, it depends. If you used common patterns (e.g. IOC, Repository), you will have a really easy time moving any app to Azure.

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