C# - Isolation In A Multi-tenant Asp.net Application
Oct 10, 2010
I'm building a multi-tenant ASP .NET application. Given that each tenant can configure their application dynamically (which may involve dynamic custom assemblies being loaded into memory), I need a means of isolating each tenant.
I'd prefer not to create a new Web Application per tenant for maintenance reasons.
I've was considering using the AppDomainManager to create an AppDomain per application, but it seems this is not intended to be used for ASP .NET applications.
I can do the database and security side with no problems, I can also get the hostname from the URL, but what I am struggling to find out is how to create the basic plumbing that would allow a new customer to sign up online, provide their company name, and for the application to create the new URL, ready to be used straight away.
im trying to build my first multi-tenant application, i used a shared database and it is complete now, i want to build the app now, and i tried this approach: all urls in the app have the following form ~/user/page.aspx(user directory is logical) where user is the current user, which is saved in a session after he logs in. when the user requests a page, say ~/user/profile.aspx, he is routed to the real page ~/profile.aspx and then his data are retrieved from the database. i dont think this is how multi tenant applications work, but i couldnt think of another method.
I have scoured the web and have yet to find and example that matches my requirements.
What I have is an existing multi-tenant asp.net application where all users authenticate against a single SQL Server database. This database also contains several other settings type data that is used within the application. Each client after authentication, utilizes thier own SQL Server database for data storage, for isolation purposes. Essentially all of the client database are identical and reside on the same server, but reside on one or more servers as well.
The application is currently written in asp.net 2.5 framework and utilizes the Micrsoft Practices Enterprise Library for DAL. Wnd we are looking to migrate to 4.0 and implement NHibernate to replace the MPEL.
I have implemented a solution already using NHibernate and the 4.0 framework, so I am familar with the concepts. I found the resources for my current session manager here as a matter of fact. But that application only had a single database, so not much too it.
The implementation is essentially what you see here:
[URL]
The other solutions that I have seen multiple config entries and/or files to manage this, but that is not desireable, since we may add new clients frequently and all of the connection information is already maintained in the authentication database.
we are building a multi-tenant application, which will support that each tenant can have a unique top level domain, the application is build using the asp.net 3.5 and SQL servr 2005, while each tenant will have different database. I have seen a number of questions about the similar applications on the StackOverFlow, but none of them is related to the Testing, I want to know is how one can test the application in a development environment, specially How can we test that each customer connects to his own DB based on the URL. how can we emulate different domains on the local system. like [URL] and [URL]all goes to dev machine's IIS.
I have been seeking the best way, or at least a good way, to handle Client Access for a Multi-Tenant/SaaS-type web app designed with MVC 2.There are no tricks as far as client customizations needed here. So every company will have the same experience on the app. I just need to understand how I can isolate the experience so that a logged in user only sees data relevant to his company. My tactic is that my database houses a "tenantID" column for each row so I can easily isolate the rows that way. I am wondering if the default provider using the ASPNETDB.mdf can be modified to route users to their assigned company data. I have seen examples using route paths ({tenant}/{controller}/{action}/{id}) but even those threads express doubts. So if anyone has a good method that they are comfortable with, I am all ears (or eyes).
I've been all around the net for weeks now trying to figure out the best way to set up a Multi-tenant website (building a web app that multiple companies and their employees will use). As far as a database goes, I am interested in using one database with a copied set of tables for each company. As far as managing the login and security in MVC2 I am lost with the myriad of examples (mostly old and not MVC) that I have seen. So ideally my app would allow a company rep to register their company and then be able to add their own employees to the site. Then all employees could login and be securely associated with their own company's tables (table names would be appended with their AccountID).
I'm not sure if this would be handled using routing or session variables or what the more ideal and up to date methods might be. Like others who have discussed this issue, it seems like this should be a much more fleshed out solution as it is becoming a more common use on the internet. I'm even willing to simplify the database down to one set of tables that stores an AccountID in each row if needed.
In a multitenant system that hosts multiple organizations and applications, where an organization may use several applications hosted on the system, should my user and role model be such that a single user or role can exist across multiple applications and organizations? Or should I limit a user entity to a single organization/application pair and then define some overarching model to tie those user entities together? That is: John Doe is a person He wants to use ApplicationA and ApplicationB He works for two different companies (just bear with me), OrganizationA and OrganizationB Should the user model be:
johndoe@someuniquesuffix is his unique user name. This gives him access to both applications for both organizations. johndoe@applicationa@organizationa is his username for ApplicationA at OrganizationA. [URL]is his username for ApplicationB at organizationA...and the same for OrganizationB. Then have some "master" list that says that all 4 user accounts for the apps/orgs correspond to the same actual "person", John Doe?
The same scenario(s) described above applies to how I will design my Role schema.
I currently have a MVC2 application hosted on premise that allows the user to add custom extensions (controllers, filters, views, validators) so that they can extend the application to suit their needs. I'm using MEF as my composition container, but MVC2 relies on the extensions (assemblies, views and scripts) to be located in a particular directory or found at runtime based on a configuration setting. The MEF catalog is instantiated at startup meaning if any new extensions are required to be added or updated then the application needs to be restarted. This is all fine in a single-tenant world but now I want to make it multi-tenant hosted in the azure cloud.
The problem I forsee is the location of the custom extensions and how they are deployed. My initial thought is to use azure blob storage (one per tenant) to store the custom extensions and then download per-session (rather than Application Startup), however in the past the way MVC has worked is it tries to resolve assemblies and find views within the current AppDomain whereas my assemblies and their embedded resources will be in memory.
I'm after a bit of advice on how to handle a multi tenant site in ASP.NET from a UI perspective. What I want to be able to offer is a choice of layouts to the client i.e.
Layout 1: Navigation horizontal at the top. Search results in a table in the middle. Some text at the bottom.
Layout 2: Navigation vertical on the left. Some text in the middle. Search results at the bottom
Layout 3, Layout 4, Layout x etc...
Each element within the various layouts can differ too. For example, the search results might look like simple list in Layout 1, but will have a completely different look in Layout 2. Once a client has decided on Layout x, I then need to apply their company identity to the layout by changing the colours, logos, etc.
My application is used by several customers, who needs to maintain their own database. Currently I'm keeping all the connectionstrings and according to the user, change it. (In a case of CRUD operation). Is this errenous way? I don't know much about MultiTenant applications. Is that the best solution for my problem?
I am developing a web application which implements membership, roles and profiles. I also want it to be multi-tenant / multi-domain. By this I mean that I will have hundreds of domain names pointing at the same web application. I want users to be able to create accounts at each individual domain. I want the opposite of "single sign on". I want users to be able to use the same username, email address and password (or different ones, at their choice) to create accounts at the different sites. I do not want users to have any awareness that the different domains have any relation to each other as they will look different and have different content. The first problem I run into is that usernames have to be unique within the forms auth aspnet db.
Well, if they want to use the same username to register on 10 different sites then I need to support that. My first thought was that instead of identifying a user by their username, I need to extend the aspnet tables and sprocs to consider the username + a unique site identifier. Is there any sample code or has anyone else ever done this before? Should I just abandon the built in aspnet forms auth and roll my own custom auth scheme? The data on the sites is not sensitive so security isn't really that important to me.
Using IIS 6, is Application Isolation happen based on the Application Pool? If so, what happens when there is more than one Virtual Directory in one Application Pool? Do they all share the same memory and if one Virtual Directory crashes, all the other apps crash as well?
Our current application is working fine but when you try to misbehave like we found out that When login with same user in multiple tab with different organization(there is a organization dropdown in the master page which sets the cookie whenever it is changed.) in tab one it is org 1 and tab 2 it is org2 , cookie has the later org 2 in it but when we go back in tab1(which had org1) and save the record org 2 will be saved with the record So can some one share some sort of a checklist with us which address these types of problem.
I am migrating an existing set of applications from Win XP to Win 7. We have a 3rd party application which is launched by and runs in the user's session which accesses a local SQL Anywhere 9 database via ODBC (launched on demand using dbeng9). On the same machine we have an ASP.NET website which also accesses the local SQL Anywhere database via ODBC. These two applications play nicely together in Win XP because both processes are running in Session 0.
In Win 7 the ASP.NET site encounters an ODBC error stating that the specified database file is already in use. This is because the 3rd party app starts first and spins up an instance of dbeng9 (via ODBC) in the user's session (usually Session 1). Then, the ASP.NET spins up and attempts to connect to the same database. The ODBC driver sees that an instance of dbeng9 is not running in the current session (Session 0) and attempts to spin up an instance at which time it is unable to access the database file because it is already in use by the logged on user in Session 1.
Does anyone have any suggestions for solving session isolation issues with local SQL Anywhere databases?
I thought about running dbeng9 as a service rather than allowing ODBC to spin up an instance on demand. However, because SQL Anywhere is bundled with the 3rd party product the PCs do not have dbsrv and I'm not sure how this would impact the licensing.
The ASP.NET site is only accessed from the local PC. Would running the ASP.NET site in a 3rd party web server cause it to execute in the user's session? (Note: because this runs on 1,000 machines a free or very low cost option is a must.)
Is the ASP.NET Development Server that is bundled with Visual Studio redistributable in this manner? Can IIS 7 or IIS 7 Express be configured to run in "local only" mode in which it executes in the user's session?
I am implementing an Isolation test in my project to ensure the data is the same in the as it was when originaly retrieved before submitting the new form data.I was wondering what would be the best way of handling this error (not an exception). The following code is the function that will determine whether or not an error should be reported, If 1 or more fields of the current record is different from the original it will return false, otherwise it will return true. How should I go about handling a false response for a best practice, Should I use a statcode and transfer to the main page displaying a message with the state code, or should I send a simple msgbox, or simply just log the error and transfer the user to main page.
I've been asked to re-write an existing VS 2003 applicatoin in VS 2010. The application contains multiple sections that allows certains users the ability to edit based on security roles. Each user is able to view the sections. There is ton of code to enable/disable section permissions for each user. Is there a better option available in VS 2010? I'm not too familiar with MVC and not sure if it would work in this scenario - each section should be available when the users login.
I'm having a hell of a time trying to debug things. Basically I want to step through each line of code to see whats happening. But when I try to step to the next line of code, 9 times out of 10 it just finishes all execution instantly without letting me step.
For example if I set a breakpoint in the thread code, that breakpoint gets hit, and I might be able to step to the next line or 2 of code, but after that the next step just jumps to the end of everything as If I had pressed F5 (continue). I assume this is happening because the context gets switched from my current thread to the main thread (or some other thread), and Visual Studio gets confused and just finishes execution, ignoring my breakpoints.
I know about the Threads window, and I have tried many different combinations of freezing and flagging different threads, but nothing accomplishes what I want. I basically want to just keep hitting F10, and step through EVERY LINE OF CODE, regardless of what thread it's in. Im surprised this isnt the default behavior.
I want to create multiinstance application in Azure. and then demontrate that if one of the instance is down other instance is working fine. How should I achive that.
I want to deploy web application which contains many projects in one solution; data layer and business logic and UserInterface (which contains the login.aspx) projects in addition to Subsonic folder for dealing with oracle Database Now, I want to run (deploy) this application in a remote IIS server I tried to copy all the solution in all its projects to the virtual directory at the IIS but it didn't work How can I do
I would like to add this feature to my web application, for the end users to chose the type of the authentication either (windows) or (Forms), and add it in the admin setting. This can be done by changing the authentication type programmatically in the code. how can I do this? Note: The user can use one type at time only.
