Creating Separate DAL Project in MVC3 Application - asp.net

I'm starting a new ASP.NET project, and I'm trying to follow the multi-project approach I've seen mentioned in multiple questions around Stackoverflow.
I managed to set up the connection string (I think) successfully, by placing it in my presentation layer's Web.config file.
<add name="MyDbContext" connectionString="Data Source=|DataDirectory|MyDb.sdf" providerName="System.Data.SqlServerCe.4.0"/>
However, when I run the following code from my BLL, no DB is created.
using (var db = new MyDbContext())
{
db.MyEntities.Add(new MyEntity()
{
EntityName = "Entity 1"
});
db.SaveChanges();
}
So first of all, where will the actual sdf file be created? I'm assuming in my DAL project. And secondly, is there any further configuration I need to perform to get this to work properly? A link to a tutorial would be splendid.
I've tried following this tutorial, but my DAL project doesn't have a Global.asax file I can play around with.

where will the actual sdf file be created?
It'll be created in the presentation layer. Make sure you have an App_Data subfolder in there. That's what bit me the first time I tried it. Also make sure that you turn on Show all files in Solution explorer or open a Windows Explorer to the App_Data subfolder to see it appear there.
but my DAL project doesn't have a Global.asax file I can play around with.
The Global.asax is living in the presentation layer, not in the DAL. The problem with the tutorial you mentioned is that it makes use of only one project. In the real world you'll likely spread this out over multiple project, typical one ASP.NET (MVC) project and several Class Library template based projects. This causes things to be put in the right project.

|DataDirectory| is a macro that evaluates to ~/App_Data/ in your web project. So look for your .sdf file in path/to/your/project/App_Data/MyDb.sdf.
You'll need to copy any other settings you added in App.config to Web.config.

Related

Copying/Moving App Code to New Project

Ok, I am in the process of breaking apart of intranet application (VS 2010 Web Site, ASP.NET Web Forms with VB code behind). During this process i'm trying to convert some of our our app_code files in to WCF rest service in a new project. However, when I copy or "add existing" vb files into the new "services" project. I get tons of errors including...
error BC30002: Type 'XXX' is not defined
warning BC40056: Namespace
or type specified in the Imports 'System.ServiceModel' doesn't
contain any public member or cannot be found. Make sure the
namespace or the type is defined and contains at least one public
member. Make sure the imported element name doesn't use any aliases.
From what i've read it may (or may not) have something to do with Assemblies and references that I just have very little knowledge on. I have added the namespaces from the current web.config to new project's web.config, and the files are identical. So there is something in the background that needs to be added to the new project I just don't know what its.
PLEASE HELP!!
THANKS
JOSH
UPDATE 1
So one of the errors i'm getting = "error BC30002: Type 'MailMessage' is not defined." Which is a namespace that is added to the web.config, which apparently isn't being picked up??? IDEAS?
I've come across a similar issue - not sure what the reasoning behind it is, but I got around it by creating a new .vb class with the same name as the one you want to copy, then copy and paste all the text from the old one to the new one. Save it, then it seems to like it - it didn't like me copying and pasting the actual file, nor did it like me adding existing files.
Hope this helps :/
This issue seems to be tied to the the differences between Web Application Projects versus Web Site Projects. Eventually I had to add different namespaces on the new project level.
Here is more info about WAP vs WSP....
http://msdn.microsoft.com/en-us/library/dd547590(v=vs.110).aspx

IIS Web application and class-library configuration - config file is lost when deployed

I have an ASP.NET web application written in C# 4.0. The application references a class library that comes with its own configuration file. At runtime, the class library uses similar to the following code to load this specific configuration:
var exeConfigPath = this.GetType().Assembly.Location;
var config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
This is done because the library has to load its bundled configuration rather than the application configuration. The application configuration should not be concerned of the library's settings and should not be able to alter them.
Now, there are a few other things that need to be done for this concept to work. I have to set the library's configuration file build operation as Content in the properties window and the Copy to be Copy Always or Copy If Newer. So far so good - the file gets automatically both into the class library's bin directory, and the web applications's bin directory, and is correctly renamed from App.config to CustomLibrary.dll.config (as supposed, the library's dll is CustomLibrary.dll).
Now I am facing two issues.
1) When I publish the web application to a filesystem location (mapped in IIS), the CustomLibrary.dll.config appears back as App.config in the bin folder of the published app. OK - I will rename it in the class library project to match the expected convention - and problem solved.
2) Even when published, the IIS compiles the application again and stores it in the ASP.NET Temporary Files. There is a fancy directory structure with a folder dedicated for each assembly referenced. The folder corresponding to the CustomLibrary.dll does not contain the config file in it. Since this.GetType().Assembly.Location will return the path to the temp folder, the application fails to load the configuration and crashes as it should.
I need to preserve the pattern of having the configuration in the class library, and be able to make it work in the web application. When manually copying the .config to the temp folder, the app works, but see, I really hate manual copying to randomly-named folders.
Is there a way to either prevent IIS from using the temp folders, or to make it copy along the config files? I believe the problem I am facing is configuration-related rather than conceptual since the application works as expected when the config file is in place. I'd prefer not to mess with using hard-coded physical paths to the config file either.
Edit:
To make it clearer, I will point out what and why I want to achieve. The idea is that the library and the web project will be developed as separate products - there will be no user or application specific information in the configuration of the library, so it will not change for different use scenarios. It is also rather specific to the class library functionality rather than the end application. It makes sense for me to keep the library's configuration information bundled within it (similar to Java, where a spring context xml file, or a properties file, get bundled with the jar of the library). I'd like to avoid having to copy the configuration in each app/web config of the consumer application. There will be cases where the consumer application is developed by third parties, and I do not want to rely on them doing their configuration right for my stuff to work. Again, the only issue here is not having the config file copied to the right place.
If those are static, internal settings that nobody should see or change, wouldn't you be better off having a file with the configuration included within the class library as an embedded resource? Either that or just a static class with the settings.
That way you'd be certain that nobody alters it, which in your scenario seems to be a plus.
I have come along a way to work arround the described issue, still not a very pleasant one to my requirements.
The solution is to take advantage of the application configuration (web.config in web apps, or app.config) which is always available. I have added as settings the absolute paths to the config file for each library. So I ended up with:
<!--
THIS IS IN THE WEB.CONFIG FILE
-->
<appSettings>
<add key ="ClassLibrary_ConfigPath"
value ="{My Publish Output Folder}\ClassLibrary.dll.config"/>
</appSettings>
and the class library now uses the following code to load its configuration:
Configuration config = null;
try
{
var exeConfigPath = this.GetType().Assembly.Location;
config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
}
catch (Exception e)
{
if (!IsConfigurationNotFoundError(e))
{
// IsConfigurationNotFoundError logic skipped for brevity
var exeConfigPath =
ConfigurationManager.AppSettings["ClassLibrary_ConfigPath"];
if (exeConfigPath != null)
{
config = ConfigurationManager.OpenExeConfiguration(exeConfigPath);
}
}
else
{
throw;
}
}
While this works, I will wait for a better solution if possible. Still, I do not have to copy the entire ClassLibrary.dll.config into the web.config file, but now I must manage filesystem locations and be aware of app-setting names. What I really want is the consumer app of the ClassLibrary.dll not to deal with its configuration in any way. If it were a desktop app, I have this covered, as Visual Studio copies the ClassLibary.dll.config appropriately. I hope there is a way to make it work smoothly for web apps.
The short answer is: you can't. You have to merge both configuration sections and place all settings in the main configuration file of your application. In case of the web application it would be the web.config. Read this

Segregating to 3 tiers from existing ASP.NET project

In my asp.net project currently i have business logic and and data access code in two sub folders(BLL,DAL) which are itself located web site project's app_code folder. I need to segregate them to two separate projects(one project for business layer and one project for Data access code).
How can I maintain connection strings necessary to Data access project which are currently in web.config file?(i.e if I choose Class library template for creating DAL and BLL projects)
How can I maintain various other web.config key values that are currently used in BLL, DAL code files?
How can I deploy compiled project? (ie Web site project I am currently deploying bin folder to Staging> production but this way where should i put DAL.dll and BLL.dll and relevant config files)
1 and 2) Add a 'using System.Configuration' and just reference them. Since their referenced in the project, asp.net will pick it up.
For example:
using System.Configuration;
namespace DataLayer
{
public class BaseDataAccess
{
public static string ConnectionString_Logging
{
get
{
return ConfigurationManager.ConnectionStrings["ConnectionString_Logging_Legacy"].ToString();
}
}
}
}
3) If properly referenced, upon compile, your BLL and DAL dlls will be in your bin folder of the main/ui project. If using web.config, your good to go.
Fundamentally, you should be wrapping those configuration bits up in objects along the way. But in any case, you can move them to a different class project without worry here -- it will pick up the configuration settings from whatever project it is hosted by, so you don't need to somehow provide the configuration to your library.
Your existing code should work, as the settings are read from the Config file of the running process, in this case your Web.Config, however i suggest you use custom configuration settings, these would be read from your Web.Config file, a typical implementation could look something like :
<YourCompany>
<YourCompany.ProjectName>
<Data ConnectionName="NameOfConnectionToUse" SomethingElse="XZY" />
<Business SomeValue="12345" />
</YourCompany.ProjectName>
</YourCompany>
Without getting into ideal settings/custom config etc, as asked - during runtime, your class libraries will get the configuration from the web.config if referenced as such from within these layers with no change. System.Configuration.AppSettings/ConnectionStrings will still work.

Problems with Web.config and App.config

Intro:
Normally we store ConnectionStrings and some other settings (<appSettings> <add key...) in the Web.config or App.config.
My scenery:
Web application using factory pattern
with direct injection to read data
providers.
In the web.config I have the key
that tells me which DLL (provider)
will I use to retrieve my data.
I can have more than one provider
(each DLL will be a provider for MS
SQL, MySQL, or get the data from
some SOA service).
Each DLL has his own name (ID and namespaces) and will need to have is own
configurations (dataconnections,
service urls, etc...) , the first
idea is to write then in the
app.config.
Problems:
#1 - The website is running (runtime) I need to change the Data Provider, how can I do this? Somehow the default value written in the Web.config will be changed.
My objective is to be able to have multiple providers (and during runtime: add/delete providers and change configurations) - this leads me to my second problem:
.
#2 - Each Data Provider has custom configurations and App.Config files do not work with dll assemblies, only executables. This means that I need to write then on my Web.Config (I do not like this option, because once again I am updating my web.config in runtime). how can I solve this?
I am trying to avoid to write a custom settings XML file. My ideal solution is to deploy somehow the DLL and DLL.config per each provider. And once again during runtime I may need to change this configuration values.
.
Ok guys, while I was waiting for some help I put my hands to work and I was able to find a good solution (in my opinion of course :P).
Let me share it with you:
So, I have one web application, or one console application, or some other kind of application, and lots of class library, and I need to store informations (different per Visual Studio project) that will change during runtime.
Storing this information inside the Web.config or App.config is not a good idea for the many problems it takes.
The other way I see it is to have one XML config file per project.
Each application will read his own XML and add it to the Cache with CacheDependency (will expire when the XML config file is updated). This way we will not need to read the configuration all the times, and we also know when the configuration is changed.
IMO THIS IS THE FASTEST AND EASIEST WAY TO SOLVE THE PROBLEM, no need to use 3rd party frameworks (neither the time it takes to learn/program it).
.
Example code:
protected void Page_Load(object sender, EventArgs e)
{
DBConfiguration cachConf;
cachConf = Cache["cachConf"] as DBConfiguration;
if (cachConf == null)
{
cachConf = new DBConfiguration();
XmlDocument doc = new XmlDocument();
doc.Load(HttpContext.Current.Request.PhysicalApplicationPath + "bin/MyConf.xml");
XmlNodeList xnl = doc.GetElementsByTagName("username");
XmlElement xe = (XmlElement)xnl[0];
cachConf.Username = xe.InnerText.ToString();
xnl = doc.GetElementsByTagName("password");
xe = (XmlElement)xnl[0];
cachConf.Password = xe.InnerText.ToString();
Cache.Insert("cachConf", cachConf,
new System.Web.Caching.CacheDependency(
HttpContext.Current.Request.PhysicalApplicationPath + "MyConf.xml"),
DateTime.Now.AddMinutes(60), TimeSpan.Zero,
System.Web.Caching.CacheItemPriority.Default,
new System.Web.Caching.CacheItemRemovedCallback(
CacheItemRemovedCallBack));
}
LabelUsername.Text = cachConf.Username;
LabelPassword.Text = cachConf.Password;
}
private void CacheItemRemovedCallBack(string key, object value, CacheItemRemovedReason reason)
{
//Response.Write("Hello world");
}
You could store the credentials in a secondary config file referenced from web.config as follows:
<appSettings file="AppSettings.config"/>
You would still need to be careful to avoid editing conflicts on the external file.
Problem 1 - Runtime changes:
The solution that Microsoft hopes you apply to this type of problem is to simply keep the web server stateless. When an ASP.NET application recycles, it lets existing requests complete new requests start on a new process. For background, read about IIS Process Recycling. A change to web.config recycle the worker process, but users will not notice this (unless you keep state in the web server process). That's the MS design.
If you want to monitor for changes without recycling a process, you'll want something other than default web.config behavior. An example that comes to mind are cruise controls project files. They have a component that maps objects to and from xml, using that, you can use the FileSystemWatcher class to monitor for changes.
Problem 2 - Custom configurations:
It sounds like you have components from different libraries that have different dependencies. Your main assembly needs a means to instantiate a service, with a given set of dependencies. The MS data provider model is cool, but not this cool.
To be this cool, use an inversion of control container, because this is exactly what they do. I like autofac (because I like the Philip K Dick reference), but castle windsor is great.
Now, if you are talking about changes databases or data providers on the fly, it may be that configuration is not the right place. If your are reporting against x databases of y types, you need a central repository of that database information, and a configuration file is not the right place, nor is an IOC container the right solution.
As Precipitous suggested, try Castle Windsor:
http://www.castleproject.org/container/
You're doing Inversion of Control manually. Windsor will take the burden off of you.

ASP.Net resource files

I'm using selenium to run some functional tests on the UI for our current application.
I want to ensure that strings from the resource files in the Web project are being displayed at the correct time and place.
Simple (I thought) all I have to do is reference the assembly of the web application and assert that the text selenium is reading from the UI matches the test in the approriate resource file.
The problem is the ASP.Net does some precomilation processing on the resource files and compiles them into an assembly called App_GlobalResources, which isn't created by the normal build process so the functional tests fail because that can't find the App_GlobalResources assembly to look the string up from.
So, any suggestions? Do I need to abandon the App_GlobalResources approach and do something manual that I have control over?
Do you understand the problem or do I need to provide more info?
My interim solution is to use SVN:Externals to pull a copy of the resx files into the test project.
I can then access them via
ResourceManager resource = new System.Resources.ResourceManager("My.Web.Namespace.resources.ImageUrls", Assembly.GetExecutingAssembly());
Its ugly because I already have a reference to the webproject (which I can probably remove now...) and I don't like mixing source files between projects. It just feels like asking for trouble but until someone suggests something better this will have to do.
Have you considered moving your GlobalResources into a separate assembly and then referencing that from both your web project and your test project? This is quite easy to do in VS 2008, and achievable but a little more difficult in VS 2005.
I was able to solve a similar problem using that approach.

Resources