I need to have this code run for each of my actions in one of my controllers. How can I do this without having to copy the code for each of the actions? Is there an init method for the controller?
System.Web.HttpSessionStateBase Sess = HttpContext.Session;
string pid = (Sess["PID"] != null ? Sess["PID"].ToString() : "");
string LogonTicket = (Sess["LogonTicket"] != null ? Sess["LogonTicket"].ToString() : "");
Why don't you wrap this up into properties in a base controller?
class abstract YourControllerBase : Controller
{
public string Pid { get { ... } }
public string LogonTicket { get { ... } }
}
You have a couple options:
Put the code in the constructor
Use OnActionExecuting
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
base.OnActionExecuting(filterContext);
}
I think although being abolutely correct, abstract classes and inheritance-based answers make an "asker" feel uncomfortable, since he is trying to work on an even simpler case then inheritace.
A short answer - just put the code into the constructor of the controller.
For example:
public HomeController: Controller {
private string _pid;
private string _logonTicket;
public HomeController() {
System.Web.HttpSessionStateBase Sess = HttpContext.Session;
_pid = (Sess["PID"] != null ? Sess["PID"].ToString() : "");
_logonTicket = (Sess["LogonTicket"] != null ? Sess["LogonTicket"].ToString() : "");
}
//REST OF YOUR CONTROLLER CODE
}
Now you can access _pid and _logonTicket from controller action's code.
Related
Hy, I'm using Attribute Routing for my project and I don't know how I can take the value of the parameter from the URL. I tried using the Request but I can't find it anywhere.
When I make GET: http://localhost:60163/courses/courseId=1 how can I take the value of 1 for courseId?
[RoutePrefix("courses")]
public class CoursesController : ApiController
{
[Route("{courseId}")] //this is the value I need in the TeacherAuthenticationAttribute Action Filter
[TeacherAuthorizationRequiered]
public async Task<IHttpActionResult> GetCourse(int courseId=0)
{
Course course = await db.Courses.FindAsync(courseId);
if (course == null)
return NotFound();
return Ok(course);
}
In TeacherAuthorizationFilter I need the value of the courseId in order to validate it.
public class TeacherAuthorizationRequieredAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(HttpActionContext filterContext)
{
if (filterContext.Request.Headers.Contains(Token))
var courseIdValue = filterContext.Request.RequestUri.ParseQueryString()["courseId"];
}
}
Here is the problem, I don't know how I can get the value using the Request or if there is another way to do it. Thank you very much!
public class TeacherAuthorizationRequieredAttribute : ActionFilterAttribute
{
private const string Token = "Token";
public override void OnActionExecuting(HttpActionContext filterContext)
{
if (filterContext.Request.Headers.Contains(Token))
var courseIdValue = filterContext.Request.RequestUri.ParseQueryString()["courseId"];
}
}
now , you have to added in request body
Token :"yourtoken"
I am stuck with this and I wonder what is the best way to approach this problem. I have a WebApi controller where I want to inject ICommand instance but I can know what is the instance I need once I inspect the Post request data. I'll give an example to be more clear but my question also applies to Winform events where you receive an event argument and depending of this event arg you want to have different implementation injected.
public class TestController : ApiController
{
public object Post(int id)
{
ICommand command = null;
if(id = 1)
{
command = new Id1Command();
}
else
{
command = new Id2Command();
}
return new object();
}
}
The only thing I can think of is creating a factory that accepts unity container as argument and inside that factory to call container.Resolve with named instance.
My problem with that is that I am taught that you shouldn't register or resolve outside your composition root and that is violation of the good practices (according Mark Seemann). I am looking for the best design for this problem in general.
I would use a CommandFactory and pass it to the TestController:
public class TestController : ApiController
{
private readonly ICommandFactory mCommandFactory;
public TestController(ICommandFactory CommandFactory)
{
mCommandFactory = CommandFactory;
}
public object Post(int id)
{
ICommand command = null;
if(id = 1)
{
command = CommandFactory.CreateId1Command();
}
else
{
command = CommandFactory.CreateId2Command();
}
return new object();
}
}
Now you have to make sure that Unity is creating the TestController. To do so, you have to implement, configure and set an IDependencyResolver. Check Dependency Injection in ASP.NET Web API 2.
Edit to your comment:
For this scenario you can use an autofactory using a functor that takes an int:
public class TestController : ApiController
{
private readonly Func<int, ICommand> mCommandFactory
public TestController(Func<int, ICommand> CommandFactory)
{
mCommandFactory = CommandFactory;
}
public object Post(int id)
{
var command mCommandFactory(id);
return new object();
}
}
The registration should look like this:
container.RegisterType<Func<int, ICommand>>(new InjectionFactory(
c => new Func<int, ICommand>(
id =>
{
if (id == 1)
{
return new Command();
}
else
{
return new Command2();
}
})));
Note: You still have to set the DependencyResolver!
I've done a few searches but haven't seem to find anything...
Using WebApi, I would like to map an input parameter to a header value: e.g.
E.g. in controller:
public User GetUser(int id){
...
return user;
}
I want WebApi to map the id parameter to a header value (e.g. X-Auth: 1234)... rather than an URL parameter.
Is this supported?
I don't think this is supported out of the box, like for example with the [FromBody] attribute.
It seems you should be able to achieve this functionality by using Model Binders, as described here. In the model binder you have access to the request and its headers, so you should be able to read the header and set its value to the bindingContext.Model property.
Edit: Reading the article further, it seems a custom HttpParameterBinding and a ParameterBindingAttribute is a more appropriate solution, or at least I would go this way. You could implement a generic [FromHeader] attribute, which does the job. I am also fighting the same problem, so I will post my solution once I have it in place.
Edit 2: Here is my implementation:
public class FromHeaderBinding : HttpParameterBinding
{
private string name;
public FromHeaderBinding(HttpParameterDescriptor parameter, string headerName)
: base(parameter)
{
if (string.IsNullOrEmpty(headerName))
{
throw new ArgumentNullException("headerName");
}
this.name = headerName;
}
public override Task ExecuteBindingAsync(ModelMetadataProvider metadataProvider, HttpActionContext actionContext, CancellationToken cancellationToken)
{
IEnumerable<string> values;
if (actionContext.Request.Headers.TryGetValues(this.name, out values))
{
actionContext.ActionArguments[this.Descriptor.ParameterName] = values.FirstOrDefault();
}
var taskSource = new TaskCompletionSource<object>();
taskSource.SetResult(null);
return taskSource.Task;
}
}
public abstract class FromHeaderAttribute : ParameterBindingAttribute
{
private string name;
public FromHeaderAttribute(string headerName)
{
this.name = headerName;
}
public override HttpParameterBinding GetBinding(HttpParameterDescriptor parameter)
{
return new FromHeaderBinding(parameter, this.name);
}
}
public class MyHeaderAttribute : FromHeaderAttribute
{
public MyHeaderAttribute()
: base("MyHeaderName")
{
}
}
Then you can use it like this:
[HttpGet]
public IHttpActionResult GetItem([MyHeader] string headerValue)
{
...
}
Hope that helps.
WebApi on DotNet Core has a has some additional attributes for extracting data from the request. Microsoft.AspNetCore.Mvc.FromHeaderAttribute will read from the request head.
public ActionResult ReadFromHeader([FromHeader(Name = "your-header-property-name")] string data){
//Do something
}
Thank you filipov for the answer.. I took your code and modified it a bit to suit my needs. I am posting my changes here in case anyone can make use of this.
I made 2 changes.
I liked the idea of the FromHeaderAttribute, but without subclassing. I made this class public, and require the user to set the param name.
I needed to support other data types besides string. So I attempt to convert the string value to the descriptor's parameterType.
Use it like this:
[HttpGet]
public void DeleteWidget(long widgetId, [FromHeader("widgetVersion")] int version)
{
...
}
And this is my FromHeaderBinding
public class FromHeaderBinding : HttpParameterBinding
{
private readonly string _name;
public FromHeaderBinding(HttpParameterDescriptor parameter, string headerName)
: base(parameter)
{
if (string.IsNullOrEmpty(headerName)) throw new ArgumentNullException("headerName");
_name = headerName;
}
public override Task ExecuteBindingAsync(ModelMetadataProvider metadataProvider, HttpActionContext actionContext, CancellationToken cancellationToken)
{
IEnumerable<string> values;
if (actionContext.Request.Headers.TryGetValues(_name, out values))
{
var tempVal = values.FirstOrDefault();
if (tempVal != null)
{
var actionValue = Convert.ChangeType(tempVal, Descriptor.ParameterType);
actionContext.ActionArguments[Descriptor.ParameterName] = actionValue;
}
}
var taskSource = new TaskCompletionSource<object>();
taskSource.SetResult(null);
return taskSource.Task;
}
}
I'm using asp.net mvc 4 and web api. My route is like this:
/api/{controller}/jqGrid/{action}/{id}
for example, if the route is :
/api/User/jqGrid/List
I hope it will route to the action name "jqGrid_List" of the User controller.
How can I achieve this?
hmm, I don't know if it's acceptable to answer my own question. I found out a solution.
First of all, I need to add a JqGridControllerConfiguration attribute to replace the default action selector applied to the controller with my one.
[JqGridControllerConfiguration]
public class UserController : ApiController
{
// GET: /api/User/jqGrid/List
[HttpGet]
public JqGridModel<User> jqGrid_List()
{
JqGridModel<User> result = new JqGridModel<User>();
result.rows = Get();
return result;
}
}
Here's the code of JqGridControllerConfiguration:
public class JqGridControllerConfiguration : Attribute, IControllerConfiguration
{
public void Initialize(HttpControllerSettings controllerSettings, HttpControllerDescriptor controllerDescriptor)
{
controllerSettings.Services.Replace(typeof(IHttpActionSelector), new JqGridActionSelector());
}
}
in JqGridActionSelector, the "action" is modified if a "jqGrid/" exists in the request URL.
public class JqGridActionSelector : ApiControllerActionSelector
{
public override HttpActionDescriptor SelectAction(HttpControllerContext controllerContext)
{
Uri url = controllerContext.Request.RequestUri;
if (url.Segments.Any(s => string.Compare(s, "jqGrid/", true) == 0))
{
controllerContext.RouteData.Values["action"] = "jqGrid_" + controllerContext.RouteData.Values["action"].ToString();
}
return base.SelectAction(controllerContext);
}
}
Not sure why you'd want to do this. But you can still create a "jqGrid_List" action in your User controller and set an ActionName for it, and it'll work.
UserController:
[HttpGet, ActionName("List")]
public string jqGrid_List()
{
return "WORKS";
}
Your Route:
routeTemplate: "api/{controller}/jqGrid/{action}/{id}"
I have a controller with two render methods that take different arguments:
class MyController
{
#RenderMapping
public void render(#ModelAttribute ClassX param)
{
// do some stuff
}
#RenderMapping
public void render2(#ModelAttribute ClassY param)
{
// do different stuff
}
}
Of course what is missing in the example above is some specification for spring to know which of the render methods to invoke. I need to decide this based on a state stored in the current session. I can't specify this just as a simple annotation, can I?
An alternative idea is something like this:
class MyController2
{
#RenderMapping
public void render(RenderRequest request)
{
if (request.getPortletSession().getAttribute(...) ...)
{
ClassX param = retrieveObjectFromRequest(ClassX.class, request);
// do some stuff
}
else
{
ClassY param = retrieveObjectFromRequest(ClassY.class, request);
// do different stuff
}
}
}
But in this case... How do I implement the retrieveObjectFromRequest method?
OK, after scrolling Spring's source code for a while I figured a way to do the retrieveObjectFromRequest part:
class MyController
{
#RenderMapping
public void render(WebRequest webRequest)
{
ClassX param = new ClassX();
new WebRequestDataBinder(param).bind(webRequest); // Fills param's properties.
}
}