Web App architecture questions - asp.net

Background:
I am an intermediate web app developer working on the .Net Platform. Most of my work has been defined pretty well for me by my peers or superiors and I have no problem following instructions and getting the job done.
The task at hand:
I was recently asked by an old friend to redo his web app from scratch. His app is extremely antiquated and he is getting overwhelmed by it breaking all the time. The app in question is an inventory / CRM application and currently each customer requires a new install of the app (usually accomplished by deploying it on a different domain on the same server and pointing to a new database).
Currently if any client wants any modifications to the forms such as additional fields, new features, etc my friend goes in and manually adds those fields to the forms, scripts, database etc. As a result all installs of this application are unique. There is no one singular source repository and no one single version of this app. Generally new features are overtime rolled into the other sites, but still this is done on an individual site by site basis.
I will be approaching this on a very modular basis. Initially I will be coding a module that will query an external web service for some data, display and store it, and periodically update it automatically. The next module will likely be for storing and displaying inventory data. This way I want to over time duplicate the current feature set of his app 100% but do it incrementally.
The Million Dollar Questions
I want to make the app have user
configurable form fields. The user
should be able to go to an admin
page, create a new forms page of a
certain category, and then specify
what fields he wants in there. He
could say 'create a new text field
called Item # and make it a
requirement" and that will get
stored somewhere. All forms will be
dynamically rendered to screen based
on what the user has configured. Is
this a good way to go about the
problem of having no idea what a
customer could want in a form? and
thus be able to store and display
form data of any sort ? What sort of
design pattern should I follow here?
I am familiar with asp.net and
the .net framework in general and
have decent knowledge of javascript,
html, silverlight, jquery, c# etc
etc. I can work my way around web
apps in a good way, but I am not
sure what sort of framework or tech
I should use to accomplish this
task. Would ASP.net 3.5 webforms be
the way to go? or should I look into
ASP.NET MVC? Do I use jquery and ajax for
complete decoupling of frontend and
backend ? or will a normal asp.net
page with some spattering of ajax
thrown in working with a codebehind
be the order of the day?
Just looking for general advice before I start.
I am currently thinking of using ASP.NET 3.5 webforms, jquery for clientside animation, ui, manipulation and data validation, and sqlserver + a .net or wcf webservice for backend.
Your advice is much appreciated as always.

I've recently implemented a white-label ecommerce system for an insurance company that allowed each partner to choose their own set of input fields, screens, and order the flow of the application to suit their individual needs.
Although it wasn't rocket science, it added complexity and increased development time.
Consider the user configuration aspect very carefully In hindsight both my client and their clients in turn, would have been happy with a more rigid system.
As for the tech side of your question, I developed my project in VS2005, using asp.net webforms and webservices with a SQLserver back end, so the stack that you're looking at is definitely capable of delivering a working product. ASP.net MVC will almost certainly help as far as testability goes.
The biggest thing I would change now if I was going to start again would be to replace the intermediate webservices with message based services using nServiceBus, MassTransit or the like. While the webservices worked fine, message based communication should be quicker and more reliable.
Finally, before you start to code, make sure that you understand the current system's functionality inside and out. If the new system doesn't do something that the old system did, it will be pretty obvious to the end users straight away.

Related

Getting started with databases

I am currently a front end developer. I know HTML and CSS pretty well, I'm OK with jQuery and know some Vanilla JS. I have an idea for a website I want to create where I will be storing data for products (data that I will be grabbing from various websites around the web). It's basically a help me choose application where the user will go through some steps and be given some choices based on their selections. This site is nothing new, but it's more for learning purposes/portfolio work.
Most of my co-workers use ASP.NET and I've seen that you can setup a website like this using ASP.NET and the provided server controls along with C#, however, I want to take another route that allows me to do the same thing NOT using ASP.NET (C# is OK and preferred if that is possible) in that I can grab data, store data, and bind data to my page.
In addition to this, I would like to do this on the Mac.
Here's a list of things I have looked at:
MongoDB (I was really confused by the setup and didn't read anywhere that this would definitely be the solution).
AngularJS
EmberJS
BackboneJS
Several other JS frameworks
Ruby on Rails
Note about the above: Some of the above might be the solution, but I don't want to start spending time learning them only to realize a week in that this is not going to help me get to my goal.
If this post would be better suited for another stack site please let me know. Thank you.
To create a basic website with a persistence you'll need to deal with three parts the front-end (client), back-end (server) and the persistence (database). Of the things that you've listed Angular, Ember and Backbone are all front-end frameworks. They each have their own way of approaching the issue but they all work in the client facing part of the project so views, interaction and dispatching data to the backend. Rails is the only thing that you've listed that's a back-end framework, another option for the back-end if you're more familiar with JS might be Node and Express. Node allows you to build a server in JS and Express is one of the more popular Node frameworks. That section will be responsible for getting the calls for data and calls with data from the front-end and dispatching the appropriate response. Rails typically works with with a SQL database like MySQL or PostGres out of the box because Rails' active record is meant to work with SQL. Mongo is a NoSQL database and I think people are getting it working with Rails but I don't know that it's highly common. Mongo's shell is pretty much javascript and it stores data as JSON (not technically but close enough) so it's been a comfortable choice for JS developers learning back-end. Either Rails or Node can get a server up and running locally on your machine so you can work with the full architecture. So what it comes down to really is picking one of each from those sections and making them play nicely together. For your purposes I would think that the way to go would be either a basic Rails app (probably with MySQL) and using jQuery ajax calls to manage some calls from the front-end or building something with the so-called MEAN stack (Mongo, Express, Angular, Node) which is all JS and using Angulars built in http functionality to handle those calls. Hope this at least narrowed the field of research a bit. Really thats a pretty open question and there are a lot of options.
What is your webhosting site? I suggestPhpmyadmin Or Mysqldatabase You can create tables and strings where you can put the websites you wanna "grab" data from and put a little javascript in there to tell your website if blahblahnlah =blahblahblah then get id="website1"
Some clarifications:
At first, you need to distinguish between a server side language (used to program the functionality) and a database (used to store data).
C# is a language of the .net framework. Regarding websites, there's no C# without ASP.net.
There are two major groups for realizing back end solutions: PHP (market share ~ 40%) and ASP (~ 25%). PHP is a programming language, ASP.net incorporates several programming languages (mainly C# and VB.net).
Both worlds are able to connect to databases: For PHP, this is mainly MySQL, for ASP.net it is mostly Microsoft SQL server.

Using Sitecore solely as a content data provider

We’re currently evaluating development with Sitecore 6 for a project. The client already bought it, so using another CMS isn't an option. The proposed setup would have Sitecore as our site’s content data provider; which would be consumed by a site built in ASP.Net MVC 3. We’d use Sitecore’s libraries to retrieve data from the Sitecore database on the server side.
In some cases, we also may want to consume content data via client side AJAX calls. I’ve been working on prototypes for this to see what data I can get back from a custom proxy service. This service calls GetOuterXml on the item, converts the Xml to JSON, and sends back the JSON to the calling script. So far, I’m finding using this method limiting; as it appears GetOuterXml only returns fields and values for fields that were set on the specific item, ignoring the template’s standard value fields and their default values for example. I tried Item.Fields.ReadAll(), still wouldn’t return the standard values. Also, there are circular references in the Item graph (item.Fields[0].Item.Fields[0]...); which has made serialization quite difficult without having to write something totally custom.
Needless to say, I've been running into many roadblocks on my path down this particular road and am definitely leaning toward doing things the Sitecore way. However, my team really wants to use MVC for this project; so before I push back on this, I feel its my responsibility to do some due diligence and reach out to the community to see if anyone else has tried this.
So my question is, as a Sitecore developer, have you ever used Sitecore as purely a content data provider on the client-side and/or server-side? If you have, have you encountered similar issues and were you able to resolve them? I know by using Sitecore in this way; you lose a lot of features such as content routing/aliasing, OMS, the rendering and layout engine; among other features. I’m not saying we’re definitely going down this path, we’re just at the R&D phase of using Sitecore and determining how it would best be utilized by our team and our development practices. Any constructive input is greatly appreciated.
Cheers,
Frank
I don't have experience with trying to use Sitecore solely as a data provider, but my first reaction to what you're suggesting is DON'T!
Sitecore offers extremely rich functionality which is directly integrated into ASP.Net and configured from within the Sitecore UI. Stripping that off and rebuilding it in MVC is lnot so much reinventing the wheel as reinventing the car.
I think that in 6.4 you can use some MVC alongside Sitecore, so you may be able to provide a sop to your colleagues with that.

extend whole website in asp.net

I'm looking for best practices and good ideas rather than a proper solution.
scenario: I work in a web agency and thus we are plenty of websites from several customers. They're built upon a cms we made, so websites are quite identical for the 90% of code. However, remaining 10% struggles me and my team as it involves not only the presentation layer but behavioral logics too (ex: a website1 requires simply user/pass registration while website2 needs more data, facebook connector, etc. But this is a very easy example).
Making ad hoc development for our customers is becoming painful as keep each version aligned is getting really hard for us
What I really dream to have is an extendible website that works by itself, but in which I can override a part. This behavior should sound like "look for the specific part, if it doesn't exists get the base one". The parts could be a method, a class, a page, a control, a static file.
example:
Suppose I want website2 to have an own login component, let's so imagine that we have a situation like:
/website_base
|_ login.aspx
/website1
/website2
|_ login.aspx
So, if I ask for www.website1.com I'll get /website_base/login.aspx, but if I ask for www.website2.com I'll get /website2/login.aspx
Any idea?
Thanks
PS: we work with asp.net 3.5 framework.
There are couple of ways to achieve this.
Approach 1:
1. Split the common functionality in modules and create a pluggable structure. (like DotNetNuke) Obviously this will be more time consuming initially but over the period of time it can make itself like a product.
Approach 2:
Firstly - I would create separate solution for each client for better maintainability. This will save me a lot of hassle while maintaining the source control and when one client comes back with issues and we have multiple releases for a single client.
Secondly - From my core solution, I will identify most commonly used artifacts for each layers and move them to a core assembly.
a. For example – In UI you can use themes to give different looks for each client. Have a default master page which comes with the core site structure. All client specific details like Logo, name, contact details etc… can be configured using some DB fields.
b. In Business Layer and Data Access Layer – core functionalities like Membership, Logging, CMS related Entities etc I would have as a dll
i. I will derive my client specific logic from these core classes.
Last but not the least – how you deploy your code and how your IIS VD structure looks like… I believe it will be totally dependent on how the solution is packaged.. I would create a deployment package for each client which will give them the ability to deploy it to any server wherever they want until you have specific issues about proprietary software hosting.
Look into ASP.NET MVC. It is much more extensible than Web Forms, can be integrated into your existing Web Forms application, and it is very easy to build reusable custom components like what you are describing.
Otherwise, I would suggest looking into WebParts and developing reusable custom server controls for the components that you need. This way you can encapsulate the complex functionality within a single UI control without having to write repetitive code. WebParts are also compatible with Personalization, which you can leverage to manage the variance between which sites use which controls.
I definitely recommend MVC as the way to go for building extensible .NET web applications, but learning a new technology always incurs a cost in the time it takes to understand the new paradigm. I hope this helps you.
I found a smart solution here: http://www.codeproject.com/KB/aspnet/ASP2UserControlLibrary.aspx
Check it out

ASP.NET Application Suite Development - Gotchas

This may sound a bit general, but I have a startup that is working on an ASP.NET (greenfield) suite of software applications. We are aiming to spend a substantial amount of time in the architecture phase to develop a strong foundation for our software. I was wondering if anyone has any advice, anything we should focus on or any suggestions for areas we should focus on to build a better suite.
Some things we are focusing on right now:
1. Session state requirements - should sessions be sticky or should we take server clustering session migration into account.
2. User login authentication - what are the major concerns in this space - LDAP, AD, custom SQL authentication systems etc.
3. The DAL - ORM vs Stored Proc
4. Integrating multiple ASP.NET applications in a single software suite. How it should look/feel. How it should be architected, etc.
I would appreciate any advice from any architects out there that have built similar systems from the ground up.
I know there are lots of solutions to session, but if you can create your framework to be session-free, you will avoid a lot of potential headaches. (There are lots of session-free options, but an obvious one is a hidden form field, somewhat like ViewState.)
Just some quick notes. I can't get too detailed since we went through this exercise where I worked last year - and I don't work there any more!
Start from the beginning using Enterprise Library, especially the Logging and Exception Handling application blocks. I've also found their Unity dependency injection library to be very useful.
Consider using Visual Studio Team Foundation Server. It's not just for source control, but can create you a complete continuous integration solution, complete with integrated bug tracking, code quality tracking, etc. If you've got the time and people, it's well worth a man-month to learn how to do an initial deployment.
You may want to buy one or more licenses of one of the Visual Studio Team System editions. You don't need these versions in order to use TFS, but they work well with it.
Consider globalization right from the start. Same with customization, if your suite will run on customer premises and be customizable by them.
You haven't said how large your team is, or is expected to be. If it's large enough, you'll want to spend at least a man-week learning a bit about what's available to you in terms of Visual Studio Extensibility. Your developers (and maybe also your QA folks) will all but live in Visual Studio, so the ability to customize it to meet your needs can be a big win. Whether it's just some macros and maybe some customized project or item templates, or whether you want to do add-ins or more, Visual Studio is very extensible.
Be certain to use WCF for any web services work. The older ASMX web service technology is now considered by Microsoft to be "legacy software".
Finally, be sure to find out whether you qualify for BizSpark, "A program that provides Software, Support and Visibility for Software Startups." And does so almost for free.
I saw a demo of Silverlight 3 at the PhillyDotNet User Group last night - WOW. Wow for business applications, not graphic applications. There is a learning curve, but you get a lot for it. For example, the demo showed a grid being bound to a table without needing to write any code.
Right out of the box you had sorting, editing, paging, etc. But it wasn't the lame stuff you normally get and then have to rework. For example the paging was smart enough to write the sql that would only bring back the 20 rows you needed for the page.
The demo continued with him putting a detail form on the page for editing. Again no code, but it was smart enough to know that it had the same datasource as the grid on the page. So as you were moving row to row on the grid - the detail form was showing the current row (and it was very fast).
Both the grid and the detail form were editable and as you changed a field in one the other would reflect the new value. The editing was smart enough to validate the field on its own. So you couldn't put a letter in a field that was an integer type, etc. It also limited the number of characters that could be entered based on the column size found in the database. All the date fields on the detail form automatically had a calendar next to them. You get the idea - no coding for any of this.
If this weren't enough, it can be used to build occasionally connected applications. So he showed how he updated a few records on a few different pages, had the option to revert back a field later (ctrl-Z), and then at the end submitted all the changed records to be saved.
Also, they said it works with Linq2SQL and the entity fraimwork.
So if I were building a new product now, I would really look into this as a way of differentiating my product. And I suspect that if you don't do it with Silverlight now, you will be rewriting it in a few years anyway.
Here is a link to a demo (not the one I saw.)
Some general thoughts. If you'd like me to expound on any of these, let me know.
Inheriting from a custom subclass of
Page instead of Page itself is a
great way to share functionality
across your site.
Nested MasterPages are good.
Charting: I've tried DevExpress,
Syncfusion, and MSChart control and
all have their own issues.
The built-in forms authentication is
pretty good. Building a site that
allows both integrated authentication
and forms authentication is tricky
but can be done.
I've tried using cross page postbacks
and I'm still not sure if I like
them.
Localization takes a lot of time
Come up with a good structure for your App_Themes and css.
Use Elmah to track unhandled exceptions

When to use ASP.NET MVC vs. ASP.NET Web Forms?

One of the common questions asked regarding ASP.NET MVC is why should you use it over ASP.NET Web Forms? The answer generally includes ViewState and clean URLs, amongst others. Towards the end you'll find a blurb about using the right tool for the job and that they serve different purposes. However, I don't believe I've ever seen what those purposes are. So, when would you actually choose ASP.NET MVC over ASP.NET Web Forms, or ASP.NET Web Forms over ASP.NET MVC?
You don't choose ASP.Net MVC over ASP.Net, because ASP.Net MVC still is ASP.Net. You do choose ASP.Net MVC or ASP.Net Web Forms, and there are lots of good reasons to do that:
Easier to get control over your HTML
Easier to do unit testing
Few "Gotchas"
On the other hand, Web Forms do have a few points in their favor:
Easy to put simple CRUD/business apps together extremely fast
Hard to beat ViewState performance in local LAN environment
Easy to learn forms paradigm
The result is that if you're building business apps in a corporate LAN environment (which honestly is still most web developers), Web Forms is really great. In that sense Microsoft really knows their market. But if you're building an app for the public internet, you might want MVC so you can test thoroughly and be sure your pages aren't bloated with unnecessary ViewState or JavaScript data.
Additionally, something that has changed over the last several years is that even many corporate intranet applications now need to support home/remote use, making MVC more attractive to that crowd than it had been.
Use MVC if all your team members are skilled enough to manage "control over HTML", otherwise your code will turn into a tag soup.
In other words
bool useMvc = true;
foreach (TeamMember member in team.Members)
{
useMvc = useMvc && member.IsSkilled;
}
http://weblogs.asp.net/shijuvarghese/archive/2008/07/09/asp-net-mvc-vs-asp-net-web-form.aspx
check that blog !
Bottom line "separation of concerns"
I'll give you a couple purposes, with clear advantages.
If your purpose is a public facing website that will be banking on traffic, use MVC. It is optimal for search engine optimization.
If your purpose is an enterprise web-application that acts like a desktop app, I would lean towards web forms, since state management and compartmentalization of your resources into underlying server controls offers huge advantages if used correctly.
The biggest problems facing developers is managing complexity and keeping code "clean". MVC gives the developer the reins to leverage OOP to tuck away complexity and make code easy on the eyes.
Webforms will be faster to develop in the short term, but it doesn't lend itself to long term sustainability in terms of maintenance and growth.
I've worked with Web forms for 13 years and MVC for 2 years now and when I started with MVC, I had similar questions. Here are my takeaways.
Most importantly: ASP.NET's latest release is 4.6 and they were moving to ASP.NET 5.0, but MS abandoned that for ASP.NET Core, which no longer supports Web Forms (or even VB.NET). So, that alone might give you your answer when deciding what rabbit hole to go down.
That being said:
MVC I'm finding, once you get the hang of it, is WAY easier for dealing with basic forms and any sort of simple "Model", aka tables with a very simple, straight-forward set of relationships such as orders that have tables that link to users, products, etc. Once you start getting into some more complicated relationships and need to return lots of conditional sets of results, rely on parameters, have complicated stored procedures... then Web Forms is much better for dealing with this. If you don't have to deal with this level of complication, MVC makes development SO MUCH faster, especially with dealing with an approach where you already have the DB because it creates so much of the code and validation for you already
If you're not very experienced with database design, MVC does the work for you. It can literally build the database for you.
MVC doesn't have a lot of the built in controls that Web Forms does (Gridviews, FormViews, Sitemaps, Paged lists). Everything has to be written from scratch, but luckily a lot of people have already invented that stuff for you in NuGet which you can just download into your project
MVC relies heavily on the structure of your URL. The path, the querystring, etc. If you find your application needing to do a lot of form POSTing instead of GET-ting, you're going to have to do a lot of tweaking or AJAX posting. If you have a set URL that can't change, it can be a pain. It's doable, but just a little tricker (or you can just use Angular instead).
MVC has no Viewstate. If you need to hide variables from post to post and persist them, it's a little difficult. MVC Does have things like ViewBag which lets you pass data from your controller to your page, but it clears after the page is rendered. There is also something called "Tempdata" which acts like Session state, but more temporary. However, it relies on Session State which is not an ideal way of persisting data. Session variables and tempdata variables are fine for user-level data (profile information for the person logged in), but having two different tabs open by the same user can cause these session/tempdata variables to overwrite each other when you're dealing with the actual model data.
If you're at a crossroads, I'd go with MVC. MS is pushing it and support for Web Forms will likely start going away

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