I'm working with Orchard CMS and it is better CMS for me. I want to understand how it does the logging and whether I can add my own logging or not. I saw that Orchard uses NullLogger class and it does no work. I've opened the App_Data.Logs folder and have seen that there are the log files. But how? I searched in code where is the trick that replaces NullLogger with log4net (I guess this is log4net, because the log format and the formatting for log4net.config are very similar) but I haven't found this.
Can somebody answer me:
How Orchard does the logging?
Whether I can add my own logger and if yes what best practices exist to do this?
Thanks, Andrey.
An Autofac module (Orchard.Logging.LoggerModule to be precise) handles that. Basically - it scans each dependency and fills all properties of type ILogger with a reference to appropriate logger instance. Each dependency gets its own logger with name equal to full type name (including namespace) of a containing class.
The NullLogger is just a placeholder so accessing the property would not throw NullReferenceExceptions before the property is being set by Autofac.
Extending the default logging is a rather complicated task as it would involve doing three things:
create a custom implementation of ILoggerFactory (just like the default Orchard.Logging.CastleLoggerFactory) and
create an Autofac module that registers that implementation in the container (like the mentioned LoggerModule does)
suppress the current default logging module by decorating your new one with [OrchardSuppressDependency("Orchard.Logging.LoggingModule")]
UPDATE
Just realized I haven't addressed the most important part of the question here:)
Yes, Orchard uses log4net so you may alter the default settings via Config/log4net.config file.
There is a great article on how Orchard Logging works. (I am not sure if it is ok to copy and paste the entire article). This is the link: Injection Logger in Orchard
So the trick is this:
Whenever a class requires a Logger instance, all it needs to do is to
declare a ILogger property, that’s it. And later, in your class, you
can use this property to Logging at anytime
And how is this done?
When Orchard web application startup, the OrchardStarter will be used
to do most of the registration work.
In a few words, it looks all the code in all projects, gets all the classes that use an ILogger property, and implements it for you (if not implemented), using Castle's logger factory.
Related
In The Olden Days
In a web.config file, settings could be placed in an appSettings section like so:
<appSettings>
<add key="mysetting" value="123"/>
</appSettings>
Even though my web.config file was in my web project, any assemblies/libraries used in that project could access the settings using:
ConfigurationManager.AppSettings["mysetting"]
Today (and the problem)
I am starting to use .NET core, and just like before, I have assemblies/libraries that are not web projects in of themselves and need to access various configuration settings.
Microsoft's Configuration documentation (https://learn.microsoft.com/en-us/aspnet/core/fundamentals/configuration) along with all of the other examples I can find, have the configuration class being consumed by a controller and don't provide any guidance on how to make it work with a class in another assembly/library that is not a controller.
For ONE example, if I have a custom attribute that I can decorate a class with and that custom attribute is defined in another library (not in a web project) and it needs to access a configuration setting, how do I do that today? I can't pass in anything to a constructor in such an instance either.
I'm going to assume you're talking about a ASPNET Core project as you specifically mention web.config.
Here's what you need to do.
IOptions<FooSettingsClass> is usually configured at application start which means that it's available at runtime with code that looks something like this.
// Adds services required for using options.
services.AddOptions();
services.Configure<AppSettings>(Configuration.GetSection("FooAppSettings"));
The easiest way is to have the framework inject it through the constructor. Typically you'll see it (as you mentioned) being injected in the controller like this:
class FooController : Controller {
public FooController(IOptions<FooSettingsClass> settings) { .
//..
}
}
If you need to access this configuration is say, a service, then you simply have a constructor, in a different assembly, which accepts those options. So:
public class SomeServiceInAnotherAssembly {
public SomeServiceInAnotherAssembly(IOptions<FooSettingsClass> settings) {
//..
}
}
This obviously means that your FooSettingsClass class needs to be outside of your ASPNET Core project (to avoid circular dependencies), but this is one way of propagating your configuration without writing any code, which is what I've seen other developers do. To me, writing code is a hoop jumping solution bound to have bugs.
Don't forget that your class (in this exampe SomeServiceInAnotherAssembly) needs to be registered at startup, i.e. services.AddScoped<SomeServiceInAnotherAssembly>();
The nice thing about this approach is that it makes your classes testable.
In 8-2017 Microsoft came out with System.Configuration.Manager for .NET CORE v4.4. Currently v4.5 and v4.6 preview.
Install this nuget package. Add directive to a code file
using System.Configuration;
Now, you can do your
var val = ConfigurationManager.AppSettings["mysetting"];
There is one trick for web sites though - you no longer use web.config for application settings and configuration sections. You use app.config as well as other types of projects. But if you deploy in ISS, you might need to use both. In web.config you supply strictly ISS-related entries. Your app-specific entries go to app.config
I am trying to implement Log4Net file appender in asp.net. I have been successful implementing it. However I am not sure about correct architecture to implement it.
I can add a logger in each page and log information. However, I was thinking to centralize the logger class. May be implement a singleton pattern. But i was wondering what will happen if a request for same page comes from two different browsers. I can implement Thread Static and then every page instead of initializing their own logger would use this centralize logger class to log.
I suppose the log4net file appender or rolling file appender using a queue mechanism to write to the log file. Because only one handle of the file can be acquired to write to a file.
Can anyone help me in this regard. Am i going the right way or i will have issues down the road when there will be tens and hundreds of requests coming from different browsers.
I recommend not to use a singleton, but instead to use a logger for each controller and class that you want to log from. Loggers are cheap to create and cached by log4net - and even more so if you declare them as static within the class - and by having one per class you can change logging per class or namespace by changing the log4net configuration at runtime - say to enable some debug logging to aid diagnosing a problem in production, or to turn down some logging which is unexpectedly noisy. You can do this without recycling your app if you have your log config in a separate file.
Also if you're going to use file logging, make sure you use MinimalLock
I've got two questions here. The first one is just specific and another one is more general, but is a source of the first one.
So, my specific problem: I want to use Encryption (actually, Hashing) algorithms with using System.Security.Cryptography namespace (for instance, SHA256Managed class).
I found out that (happily) Xamarin has implemented those in System.dll.
But it is not portable and obviously can not be used from Core application directly.
But I've also found another great project -- PclContrib -- which allows you to do that. But, unfortunately, they don't have the implementation for Touch and Android. (However, that still works great for Desktop (Web) and Windows Phone, plus, still can be included into Core (as it uses portable project)).
Anyway, to solve that nicely, I've decided to create some base class for the encryption methods and then override core methods which require the custom dll (for any custom system).
The way I did it (at least, trying to do) was:
Defining virtual method in Core App base class:
public virtual IEncryptionProvider CreateEncryptionProvider()
Overriding Core App class in Touch project with overriding CreateEncryptionProvider (which creates an instance of TouchEncryptionProvider class instance).
Core:
public class App : MvxApplication
Touch:
public class AppTouch : App
Launching it in Touch setup.cs:
protected override Cirrious.MvvmCross.ViewModels.IMvxApplication CreateApp (
{
return new AppTouch();
}
But, that does not work for me. On startup I've got this exception message in log:
"Exception masked KeyNotFoundException: Could not find view for Mynamespace.Etc.LoginViewModel", which works fine when I do new App() instead. I am not sure if that message shows actual problem (as before it was saying the same even that was a problem with some third-party dll, unrelated to views at all). But speaking shortly, that's just a primitive inheritance of App : MvxApplication, but placed not in Core but Touch project.
So, does it requeire some more custom initialization for such situations or do I miss something else?
And, actually, more general question is how should I build such Multiplatform approaches? Actually, now I've got similar problem with HttpUtility.UrlEncode, which I would want to use in my Core project.
What is the MvvmCross "philosophy" to handle such situations?
Thank you.
For the 'viewmodel not found' problem, this is caused because mvvmcross by default only looks for viewmodels in the Assembly containing your app.
If you want it to look in other assemblies, override ViewModelAssemblies in Setup.cs - see how this done in, for example, MvvmCross - structuring shared View Models and Views
For general multplatform approach, please read questions and answers like:
Platform-specific IoC in MVVMCross
Instantiation of ViewModels and Service classes
Please also remember you don't have to use PCLs - if you prefer to use file-linking between multiple platform-specific core projects, then you can of course use this approach.
Finally, please also try to ask one question per question - I find it makes stackoverflow work better for users and with search engines too. If you need to link questions, then you can just add a hyperlink reference - stackoverflow then marks them as related.
I'm starting with a Symfony2 project. I know the framework basics but I have a question:
Where is the right place to pot those helper classes I create for help or for the business logic?
Max's answer is correct. However I question the path he recommends for your code.
The following classes and files have specific emplacements:
Service Container Extensions (belong in) DependencyInjection/
from http://symfony.com/doc/current/cookbook/bundles/best_practices.html
That says your Services should be placed in a folder called 'DependencyInjection', not 'Services'. In full, it should be src/Foo/BarBundle/DependencyInjection
I say this as someone that had the former and has just finished moving them all to the latter (!)
What #Adam says is wrong, you have to store your Dependency Injection Extensions in DependecyInjection directory, not the services itself. In the documentation says that you can store your (custom) business logic classes in any place you like.
http://symfony.com/doc/current/best_practices/business-logic.html
The best way to keep the business logic is create service to handle all the logic. So it will be in:
src/Foo/BarBundle/Service
and you need to call the service in the services.yml.
I recently did some small work on an existing Symfony2 project. As described by answer from Tuong Le, I created my Helper classes under the Helper directory of the bundle and class name with Helper suffix i.e. the helper class is located at:
src/MyBundle/Helper/MyUtilHelper.php
I can use MyUtilHelper class in my bundle without calling the service container i.e. I didn't need to call.
$container->get('my_util');
I don't really know whether there is some special config. in my setup; someone already got it setup and I was just adding new functionality.
You can create the custom classes under your Bundle, such as under a folder Helper/..
However, to use those helper in your code, you'll need to define those Helper(s) in your service description file (such as services.xml)... Then you can use $container->get('your_helper')->
According to official documentation - in particular - Symfony Best Practices - you should store your services in Utils folder under the src. I belive, that this is correct way regardless of whether you want or don't wont to make the functionality provided by services of your bundle available to other parts of application via Service Container. Furthermore, you can store helper classes in any place you consider suitable. Concerning #Adam Knowles and #PachinSV answers - they are not quite right because they do not answer your question - "Where is the right place to pot those helper classes I create for help or for the business logic?" or "Where to store classes which I want to register and use via Service Container" - but not where to put bundle Extension class - which main purpose is to provide information about configuration which should be automatically loaded from your bundle to apps Service Container during the process of booting the Kernel.
Can anyone help point me to some good resources for working with Unity 2.0 in an ASP.NET that doesn't talk about ASP.NET MVC?!?
We are not using MVC and I am struggling to get Unity to inject dependencies into my pages following the couple of examples I've read (which are all based on David Hayden's work so they are all presenting the same examples and code).
UPDATE
I tried to go the PageHandlerFactory route but the example (here) is incomplete and no source code is available to accompany the article.
So, I decided to try the custom HttpModule approach described here and here. Again, no source code is available beyond what is shown so it is difficult to troubleshoot issues.
The problem I have now is that all of the plumbing appears to be wiring up correctly but the Buildup method does nothing to my page. I can see all of the types are registered in the container when I set a break-point in the module code and the code is executing as expected. But a break-point in the Page_Load event handler shows that the dependencies are all null.
The property in question is public, with a setter and getter, and is marked with the Dependency attribute. I've tried with and without the attribute, with and without a mapping name, ... every combination I could think of and nothing works.
What am I missing???
It depends what you expect. Most exemples targeting MVC present custom controller factory which allows creating controllers with dependency injection. This is indeed also possible with web forms but instead of controller you must inject dependencies into pages. To do this you must replace PageHandlerFactory with custom implementation.
You can create your own implementation of PageHandlerFactory which will be able to resolve pages directly and inject dependencies defined in constructor or you can use one of these (here, here and here) which instead uses stantandard PageHandlerFactory and builds page instance (resolve property dependencies).