Consume JSON REST Service via WCF Message Class

Consume JSON REST Service via WCF Message Class

Since WCF was designed and envisioned by Microsoft the world has changed and the use of RESTful JSON based web services has increased at the expense of SOAP based services. WCF was updated to reflect this change and for several years has supported RESTful services through webHTTPBinding etc (more on MSDN), and there are many resources on the web for how to consume or host a REST service with WCF, but many of these assume you are not using a generic channel factory approach with the low-level message class. Usually in WCF you would consume a service via a proxy, or perhaps by directly creating a Channel Factory, however these require explicit knowledge of the service contract being consumed and sometimes a more generic solution is required. If, for example, you wanted to create a  generic WCF helper class for your application which would build a message directly from passed in data and call a service generically then you could use the Message class directly. This advanced approach is documented for SOAP messaging, but what about if you need to send JSON?

Below are some notes on how you would use the Message class to send JSON in a generic way (i.e. without needing intimate knowledge of the service contract you’re calling).

In the code below we need to pass the Person object named “bob” as JSON so we create a WebChannelFactory and use the “Endpoint1” config (which is very generic in nature). The special WebChannelFactory is a ChannelFactory that automatically adds WebHttpBinding and WebHttpBehavior to the endpoint config if its missing. Then we create a proxy and directly build a Channels.Message class using a SOAP version of “None” (as we’re not using SOAP here but JSON) and the DataContractJsonSerializer .

Person bob = new Person() {age = 89, name="Bob"};

WebChannelFactory factory = new WebChannelFactory("Endpoint1");

IRequestChannel proxy = factory.CreateChannel(
      new EndpointAddress("http://localhost:8080/Test"));

System.ServiceModel.Channels.Message requestMsg = 
      System.ServiceModel.Channels.Message.CreateMessage(
          MessageVersion.None, "", bob, new DataContractJsonSerializer(typeof(Person)));

requestMsg.Headers.To = new Uri(factory.Endpoint.Address.ToString());
requestMsg.Properties[WebBodyFormatMessageProperty.Name] = new WebBodyFormatMessageProperty(WebContentFormat.Json);

You will notice above we also need to set the message header URI too and also set the WebBodyFormatMessageProperty format to JSON. If we forget to do this step then the message will be sent in XML format despite the previous web config we have set (for more info on this issue see here and here). This is what is sent without setting the WebBodyFormatMessageProperty to JSON:

<root type="object"><age type="number">89</age><name>Bob</name></root>

and with the WebBodyFormatMessageProperty set to “WebContentFormat.Json”:

{“age”:89,”name”:”Bob”}

Next we call the nice and generic “Request()” method on the proxy and handle the response, picking out the body and de-serialising it into a Person object via the DataContractJsonSerializer.

System.ServiceModel.Channels.Message responseMsg = proxy.Request(requestMsg);

Person BobResponse = responseMsg.GetBody(new DataContractJsonSerializer(typeof(Person)));

Endpoint Config:

<system.serviceModel>
 <client>
 <endpoint name="Endpoint1"
 address="http://localhost:8080/Test" 
 binding="webHttpBinding"
 contract="System.ServiceModel.Channels.IRequestChannel"
 />
 </client>
</system.serviceModel>

In this snippet the only thing that is specific to the service being called is the Person object which the DataContractJsonSerializer needs to know about in order to be able to serialise it into JSON correctly. The actual service call is generic. To make this a completely generic helper we can instead pass in a type for the DataContractJsonSerializer to use instead of a real object, leaving the calling component to pass the right type in when it calls this generic helper method.

If you are already using this message class approach for SOAP services and need to now call some JSON REST services then hopefully this will help.

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Create New MSTest Projects for Pre .Net 4.5 in Visual Studio 2017

Create New MSTest Projects for Pre .Net 4.5 in Visual Studio 2017

This post outlines the steps to create a new unit test project in Visual Studio 2017 using MS Test V1 and that targets .Net Frameworks prior to .Net 4.5.

Visual Studio 2017 onwards only has new unit test projects for MS Test V2 onwards and .Net 4.5. This is fine for new applications or ones targeting a recent .Net framework version but what if you have an existing solution targeting an older .Net version. Below shows the Unit Test Project available for .Net 4.5, but as you can see in the second screenshot for .Net 3.5 its not available.

NewTestProj_45

NewTestProj_35

If you want to create a new unit test project targeting .Net 3.5/4 for example then follow the steps below:

Create a new MS Test V2 project targetting .Net Framework 4.5 as in the first screenshot above (i.e. File > New Project > Test > Unit Test Project targeting .Net 4.5).

Once its created, change the project to target your earlier .Net Framework (e.g. .Net 3.5). This is done via the Project Properties page.  Click Yes and Visual Studio will reload the project.

NewTestProj_ChgFmk

Once it reloads the project will complain about some references which is fine as we’re now going to remove the MS Test V2 assemblies.

NewTestProj_Errors

Now remove the two project references to test assemblies.

NewTestProj_RemoveRefs

Then add a reference to the MSTest v1 assembly, Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll.  This should be under Extensions in the Add Reference dialog. Alternatively you can browse to them on your hard drive at the following locations:

For pre .Net 4 projects : C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\ReferenceAssemblies\v2.0

For post .Net 4 projects: C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\Common7\IDE\ReferenceAssemblies\v4.0

If you are not running Visual Studio Enterprise, then swap Enterprise in the path for Community etc.

NewTestProj_AddRefs

Now rebuild the project and you’re all done.

Find assemblies loaded during debugging in Visual Studio

Find assemblies loaded during debugging in Visual Studio

Sometimes you may get the following error when you are debugging a .Net app in Visual Studio:

“The breakpoint will not currently be hit. No symbols have been loaded for this document.”

Or you may have issues whereby the wrong code version appears to be loading at run time or perhaps when debugging you get an error saying a referenced component cannot be located.

All these issues stem from you not being able to view what components are actually being loaded during debug. If only there was a view in Visual Studio that gave you that info…well this is Visual Studio and so they’ve already thought of that, and its called the Modules view.

During debugging of your application from the menu go : Debug > Windows > Modules

Mod1

From this really useful view you can see each component that’s been loaded, the file path, the symbol file location, version information and more. This will show you if a component from the GAC has been loaded instead of your local file version, for example. It also enables you to find and load Symbol files for components where they have not been loaded automatically.

For information on the full functionality of this view check out the documentation here.

Platform Targeting in .Net

Platform Targeting in .Net

If you see one of the errors below within your .Net application it is likely as a result of your assembly having been compiled with the wrong target architecture flag set.

1) In this instance the assembly was accidentally compiled for x86 only and run within IIS in a 64bit process:

Unhandled Exception: System.BadImageFormatException: Could not load file or assembly “AssemblyName Version=1.0.0.0, Culture=neutral” or one of its dependencies. An attempt was made to load a program with an incorrect format.

(For info IIS has an Application Pool setting under Advanced  Settings that enables you to run the App Pool as a 32 bit process instead of 64bit. This is off by default.)

2) Here a .Net application targeting a 64 bit processor was run on a 32bit system:

This version of ConsoleApplication1.exe is not compatible with the version of Windows you’re running. Check your computer’s system information to see whether you need a x86 (32-bit) or x64 (64-bit) version of the program, and then contact the software publisher.

If you are looking for a quick fix, then just recompile your assembly with the “Any CPU” option as your platform target. See project properties, build tab for this setting.  If you want more information and explanation then read on.

BlgPlatformTarget1When compiling .Net assemblies in Visual Studio (or via the command line) there are a few options regarding optimising for certain target platforms. If you know that your assembly needs a to be deployed only to a 32bit environment (or it needs to target a specific processor instruction set) then you  can optimise the output of MSIL code (what the compiler produces ready for a JIT compilation at run time) for that platform. This is not normally required but perhaps, for example, you have to reference unmanaged code that targets a specific processor architecture.

Essentially this sets a flag inside the assembly metadata that is read by the CLR. If this is set incorrectly then this can result in the above errors but also other odd situations. For example if you compile your app to target “x86”  and then reference an assembly that is targeting a “x64” platform then you will see an error at runtime due to this mismatch (BadImageFormatException). Running an “x86” application will still work on a 64 bit Windows but it will not run natively as 64bit but will instead run under the WOW64 emulation mode which enables x86 execution under 64 bit  (with a performance overhead), which may or may not be a valid scenario in your case.

If you want to reproduce the situation try creating a new console application and in the build properties tab set Platform Target to “x86”. Then create a new Class Library project, set a reference to it in the Console Application, and then in the build properties tab set it to target the “x64” platform. Build and run the application which will show the above BadImageFormatException.

The target platform for your project is set in the Project Properties tab in Visual Studio, under Build (see screenshot above). If you are compiling via the command line you use the /platform switch.

“AnyCPU” became the default value from VS2010 onwards. “AnyCPU” used up to .Net 4.0 means that if the process runs on a 32-bit system, it runs as a 32-bit process and MSIL is compiled to x86 machine code. If the process runs on a 64-bit system, it runs as a 64-bit process and MSIL is compiled to x64 machine code. Whilst this enables more compatibility with multiple target machines it can lead to confusion or unexpected results when you consider that Windows duplicates system DLLs, configuration and registry views for 32bit and 64bit processes.  So Since .Net 4.5 (VS2012)  there is now a new default subtype of “AnyCPU” called “Any CPU 32-bit preferred” which basically follows the above rules except that if a process runs on 32bit system then it will run as a 32 bit process (not 64bit as before) and its MSIL will be compiled to x86 code not x64. This change essentially now forces your process to run under 32bit on a 64bit machine unless you untick the option and turn off the default setting. This setting can be seen on Project properites Build tab as “Prefer 32-bit”.

BlgPlatformTarget2

It is worth noting that you may see a confusing “Multiple Environments” option in Visual Studio which can be automatically added  after migrating solutions from older versions of Visual Studio (I believe it has been removed as a new option in VS2015 onwards but can hang around in older solutions). Use the Configuration Manager tab to check the setting for each assembly. Most developers will want to target  “Any CPU” which supports multiple target environments. If you are getting the above errors then use the steps below to check the assembly and if incorrect then try recompiling with “Any CPU” instead.

How to confirm a target platform for a given assembly:

So how do you confirm which processor architecture an assembly was built for? Well there are a few ways:

1) Using .Net reflection via a simple Powershell command:

[reflection.assemblyname]::GetAssemblyName("${pwd}\MyClassLibrary1.dll") | format-list

Running this command pointing to the assembly you want to check will produce output like this below (results truncated):

An assembly compiled to target AnyCPU:

Name                  : ClassLibrary2
Version               : 1.0.0.0
CodeBase              : file:///C:/TempCode/crap/pttest/x86/ClassLibrary2.dll
ProcessorArchitecture : MSIL
FullName              : ClassLibrary2, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null

Same assembly but now compiled to target x86 :

Name                  : ClassLibrary2
Version               : 1.0.0.0
CodeBase              : file:///C:/TempCode/crap/pttest/x86/ClassLibrary2.dll
ProcessorArchitecture : X86
FullName              : ClassLibrary2, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null

Same assembly again but now compiled to target x64 :

Name                  : ClassLibrary2
Version               : 1.0.0.0
CodeBase              : file:///C:/TempCode/crap/pttest/x86/ClassLibrary2.dll
ProcessorArchitecture : Amd64
FullName              : ClassLibrary2, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null

 

2 )You can also see this information from a de-compiler tool such as dotPeek. Below shows a screenshot showing a x86, 64, AnyCPU and x64 targeted assemblies.
BlgPlatformTarget4_dotPeek

3) Use the CorFlags Conversion Tool

The CorFlags Conversion Tool (CorFlags.exe) is installed with Visual Studio and easily accessed by the VS Command Line. It enables reading and editing of flags for assemblies.

CorFlags  assemblyName

Assuming you have the .Net 4 version installed with .net 4 and above  you’ll see something like this. Older versions do not have the 32BITREQ/PREF flags as per the change for .Net4 discussed above:

Microsoft (R) .NET Framework CorFlags Conversion Tool.  Version  4.6.1055.0
Copyright (c) Microsoft Corporation.  All rights reserved.

Version   : v4.0.30319
CLR Header: 2.5
PE        : PE32
CorFlags  : 0x1
ILONLY    : 1
32BITREQ  : 0
32BITPREF : 0
Signed    : 0

To interpret this output see the table below and check the PE value (PE32+ only on 64bit) and the 32bit Required/Preferred flags. It is also possible to update these flags using this tool.

Summary

Below is a simple table of results to show the impact of Platform Target on the complied assembly and how it is run on a 32/64bit OS. As you can see the 32 preferred flag has resulted in an AnyCPU assembly being run as 32bit on a 64bit OS, the table also shows the values you get when you use the techniques above for determining the target platform for a given assembly.

 

Platform Target in Visual Studio PowerShell
Result
dotPeek
Result
CorFlags
32BITREQ
CorFlags
32PREF
CorFlags
PE
Runs on
32bit OS as
Runs on
64bit
OS as
AnyCPU (pre .Net 4) MSIL MSIL 0 0 PE32 32 bit process 64 bit process
AnyCPU (.Net 4 +)
32 bit NOT preferred
MSIL MSIL 0 0 PE32 32 bit process 64 bit process
AnyCPU (.Net 4 +)
32 bit Preferred (default)
MSIL x86 0 1 PE32 32 bit process 32 bit process
(under WOW64)
x86 x86 x86 1 0 PE32 32 bit process 32 bit process
(under WOW64)
x64 Amd64 x64 0 0 PE32+ ERROR 64 bit process

In summary, there are a few simple rules to be aware of with using AnyCPU and the 32bit Preferred flag but essentially AnyCPU will enable the most compatibility in most cases.

Break on Exceptions in Visual Studio 2015

Break on Exceptions in Visual Studio 2015

Looking for the option to break on exceptions during debugging in Microsoft Visual Studio 2015? Well Microsoft dumped the old exceptions dialog and replaced it with the new Exception Settings Window. To see it to show that window via the menu: Debug > Windows > Exception Settings.

vsexceptionsettingsmenu

Use the Exception Settings window to choose the types of exceptions on which you wish to break. Right click for the context menu option to turn on/off the option to break or continue when the exception is handled (see below). To break on all exceptions you’ll want to ensure this is set to off (not ticked).

vs2015exceptionssettingsdiag2

For more information check out these MSDN links:

https://blogs.msdn.microsoft.com/visualstudioalm/2015/02/23/the-new-exception-settings-window-in-visual-studio-2015/

https://blogs.msdn.microsoft.com/visualstudioalm/2015/01/07/understanding-exceptions-while-debugging-with-visual-studio/

Preventing Browser Caching using HTTP Headers

Preventing Browser Caching using HTTP Headers

Many developers consider the use of HTTPS on a site enough security for a user’s data, however one area often overlooked is the caching of your sites pages by the users browser. By default (for performance) browsers will cache pages visited regardless of whether they are served via HTTP or HTTPS. This behaviour is not ideal for security as it allows an attacker to use the locally stored browser history and browser cache to read possibly sensitive data entered by a user during their web session. The attacker would need access to the users physical machine (either locally in the case of a shared device or remotely via remote access or malware). To avoid this scenario for your site you should consider informing the browser not to cache sensitive pages via the header values in your HTTP response. Unfortunately it’s not quite that easy as different browsers implement different policies and treat the various cache control values in HTTP headers differently.

Taking control of caching via the use of HTTP headers

To control how the browser (and any intermediate server) caches the pages within our web application we need to change the HTTP headers to explicitly prevent caching. The minimum recommended HTTP headers to de-activate caching are:

Cache-control: no-store
Pragma: no-cache

Below are the settings seen on many secure sites as a comparison to above and perhaps as a guide to what we should really be aiming for:

Cache-Control:max-age=0, no-cache, no-store, must-revalidate
Expires:Thu, 01 Jan 1970 00:00:00 GMT
Pragma:no-cache

HTTP Headers & Browser Implementation Differences:

Different web browsers implement caching in differing ways and therefore also implement various subtleties in their support for the cache controlling HTTP headers. This also means that as browsers evolve so too will their implementations related to these header values.

Pragma Header Setting

Use of the ‘Pragma’ setting is often used but it is now outdated (a retained setting from HTTP 1.0) and actually relates to requests and not responses. As developers have been ‘over using’ this on responses many browsers actually started to make use of this setting to control response caching. This is why it is best included even though it has been superseded by specific HTTP 1.1 directives.

Cache-Control ‘No-Store’ & ‘No-Cache’ Header Settings

A “Cache-Control” setting of private instructs any proxies not to cache the page but it does still permit the browser to cache. Changing this to no-store instructs the browser to not cache the page and not store it in a local cache. This is the most secure setting. Again due to variances in implementation a setting of no-cache is also sometimes used to mean no-store (despite this setting actually meaning cache but always re-validate, see here). Due to this the common recommendation is to include both settings, i.e: Cache-control: no-store, no-cache.

Expires Header Setting

This again is an old HTTP 1.0 setting that is maintained for backward compatibility. Setting this date to a date in the past forces the browser to treat the data as stale and therefore it will not be loaded from cache but re-queried from the originating server. The data is still cached locally on disk though and so only provides little security benefits but does prevent an attacker directly using the browser back button to read the data without resorting to accessing the cache on the file system.  For example:  Expires: Thu, 01 Jan 1970 00:00:00 GMT

Max-Age Header Setting

The HTTP 1.1 equivalent of expires header. Setting to 0 will force the browser to re-validate with the originating server before displaying the page from cache. For example: Cache-control: max-age=0

Must-Revalidate Header Setting

This instructs the browser that it must revalidate the page against the originating server before loading from the cache, i.e. Cache-Control: must-revalidate

Implementing the HTTP Header Options

Which pages will be affected?

Technically you only need to turn off caching on those pages where sensitive data is being collected or displayed. This needs to be balanced against the risk of accidently not implementing the change on new pages in the future or making it possible to remove this change accidently on individual pages. A review of your web application might show that the majority of pages display sensitive data and therefore a global setting would be beneficial. A global setting would also ensure that any new future pages added to the application would automatically be covered by this change, reducing the impact of developers forgetting to set the values.

There is a trade off with performance here and this must be considered in your approach. As this change impacts the client caching mechanics of the site there will be performance implications of this change. Pages will no longer be cached on the client, impacting client response times and may also increase load on the servers. A full performance test is required following any change in this area.

Implementing in ASP.net

There are numerous options for implementing the HTTP headers into a web application. These options are outlined below with their strengths/weaknesses. ASP.net and the .Net framework provide methods to set caching controls on the Request and Cache objects. These in turn result in HTTP headers being set for the page/application’s HTTP responses. This provides a level of abstraction from the HTTP headers but that abstraction prevents you setting the headers exactly how you might like them for full browser compatibility. The alternative approach is to explicitly set the HTTP headers. Both options and how they can be implemented are explored below:

Using ASP.net Intrinsic Cache Settings
Declaratively Set Output Cache per ASPX Page

Using the ASPX Page object’s attributes you can declaratively set the output cache properties for the page including the HTTP header values regarding caching. The syntax is show in the example below:

Example ASPX page:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="CacheTestApp._Default" %> 
<%@ OutputCache Duration="60" VaryByParam="None"%> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml" > 
<head runat="server"> 
<title></title> 
</head> 
<body> 
<form id="form1" runat="server"> This is Page 1.</form> 
</body> 
</html>

Parameters can be added to the OutputCache settings via the various supported attributes. Whilst this configuration allows specific targeting of the caching solution by enabling you to define a cache setting for each separate page it has the drawback that it needs changes to be made to all pages and all user controls. In addition developers of any new pages will need to ensure that the page’s cache settings are correctly configured. Lastly this solution is not configurable should the setting need to be changed per environment or disabled for performance reasons.

Declaratively Set Output Cache Using a Global Output Cache Profile

An alternative declarative solution for configuring a page’s cache settings is to use a Cache Profile. This works by again adding an OutputCache directive to each page (and user control) but this time deferring the configuration settings to a CacheProfile in the web.config file.

Example ASPX page:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="CacheTestApp._Default" %> 
<%@ OutputCache CacheProfile=" RHCacheProfile "%> 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml" > 
<head runat="server"> 
<title></title> 
</head> 
<body> 
<form id="form1" runat="server"> 
This is Page 1. 
</form> 
</body> 
</html>

Web.config file:

<system.web> 
<caching> 
<outputCache enableOutputCache="false"/> 
<outputCacheSettings> 
<outputCacheProfiles> 
<OutputCache CacheProfile=" RHCacheProfile"> 
<add name="RHCacheProfile" 
location="None" 
noStore="true"/> 
</outputCacheProfiles> 
</outputCacheSettings> 
</caching> 
</system.web>

This option provides the specific targeting per page and the related drawbacks of having to make changes to every page and user control. This solution does provide the ability to centralise the cache settings in one place (minimising the impact of future changes) and enables caching to be set during installation depending on target environment via the deployment process.

Programmatically Set HTTP Headers in ASPX Pages

Output caching can also be set in code in the code behind page (or indeed anywhere where the response object can be manipulated). The code snippet below shows setting the HTTP headers indirectly via the Response.Cache object:

Response.Cache.SetCacheability(HttpCacheability.NoCache); 
Response.Cache.SetExpires(DateTime.UtcNow.AddHours(-1)); 
Response.Cache.SetNoStore();
Response.Cache.SetMaxAge(new TimeSpan(0,0,30));

This code would need to be added to each page and so results in duplicate code to maintain and again introduces the requirement for this to be remembered to be added to all new pages as they are developed. It results in the below headers being produced:

Cache-Control:no-cache, no-store

Expires:-1

Pragma:no-cache

 

Programmatically Set HTTP Headers in Global ASAX File

Instead of adding the above code in each page an alternative approach is to add it to the Global ASAX file so as to apply to all requests made through the application.

void Application_BeginRequest(object sender, EventArgs e)
{
	Response.Cache.SetCacheability(HttpCacheability.NoCache);
	Response.Cache.SetExpires(DateTime.Now);
	Response.Cache.SetNoStore();
	Response.Cache.SetMaxAge(new TimeSpan(0,0,30));
}

This would apply to all pages being requested through the application. It results in the below headers being produced:

Cache-Control:no-cache, no-store

Expires:-1

Pragma:no-cache

 

Explicitly define HTTP Headers outside of ASP.net Cache settings.

Explicitly Define HTTP Headers in ASPX Pages

The response object can have its HTTP Headers set explicitly instead of using the ASP.net Cache objects abstraction layer. This involves setting the header on every page:

void Page_Load(object sender, EventArgs e)
{
	Response.AddHeader("Cache-Control", "max-age=0,no-cache,no-store,must-revalidate");
	Response.AddHeader("Pragma", "no-cache");
	Response.AddHeader("Expires", "Tue, 01 Jan 1970 00:00:00 GMT");
}

Again as a page specific approach it requires a change to be made on each page. It results in the below headers being produced:

Cache-Control:max-age=0,no-cache,no-store,must-revalidate

Expires:Tue, 01 Jan 1970 00:00:00 GMT

Pragma:no-cache

Explicitly Define HTTP Headers in Global ASAX File

To avoid having to set the header explicitly on each page the above code can be inserted into the Application_BeginRequest event within the application’s Global ASAX file:

void Application_BeginRequest(object sender, EventArgs e)
{
	Response.AddHeader("Cache-Control", "max-age=0,no-cache,no-store,must-revalidate");
	Response.AddHeader("Pragma", "no-cache");
	Response.AddHeader("Expires", "Tue, 01 Jan 1970 00:00:00 GMT");
}

Again this results in the below headers being produced:

Cache-Control:max-age=0,no-cache,no-store,must-revalidate

Expires:Tue, 01 Jan 1970 00:00:00 GMT

Pragma:no-cache

Environment Specific Settings

It’s useful to be able to set the header values via configuration settings, not least to be able to test this change in a performance test environment via before/after tests.

All of the above changes should be made configurable and be able to be triggered/tweaked via the web.config file (and therefore can be modified via deployment settings).

Useful Links For More Information

Upgrading MVC 3 to MVC 4 via NuGet

Upgrading MVC 3 to MVC 4 via NuGet

I had to upgrade an old ASP.NET MVC 3 project to MVC 4 yesterday and whilst searching for the official instructions I found that there is a NuGet package that does all the hard work for you.

The official instructions for upgrading are in the MVC 4 release notes here: http://www.asp.net/whitepapers/mvc4-release-notes#_Toc303253806

But Nandip Makwana has created a NuGet package that automates this process. Check it out here: https://www.nuget.org/packages/UpgradeMvc3ToMvc4

It worked great for me.

Host Static HTML or WebForms Page within MVC Site

Host Static HTML or WebForms Page within MVC Site

If you need to host a static HTML page within an ASP.net MVC website or you need to mix ASP.net WebForms with an MVC website then you need to configure your routing configuration in MVC to ignore requests for those pages.

File:Belgian road sign F7.svgRecently I wanted to host a static HTML welcome page (e.g. hello.htm) on an MVC website. I added the HTML page to my MVC solution (setting it as the Visual Studio project’s start page) and configured my web site’s default page to be the HTML page (hello.htm). It tested ok at first but then I realised that it was only displaying the hello page first on debug because I’d set the page to be the Visual Studio project’s start-up page and I hadn’t actually configured the MVC routes correctly so it wouldn’t work once deployed.

For this to work you need to tell MVC to ignore the route if its for the HTML page (or ASPX page in the case of mixing WebForms and MVC). Find your routing configuration section (for MVC4 it’s in RouteConfig.cs under the App_Start folder, for MVC1,2,3 it’s in Global.asax). Once found use the IgnoreRoute() method to tell Routing to ignore the specific paths. I used this:

routes.IgnoreRoute("hello.htm"); //ignore the specific HTML start page
routes.IgnoreRoute(""); //to ignore any default root requests

Now MVC ignores a request to load the hello HTML page and leaves IIS to handle returning the resource and hence the page displays correctly.

Setting a Custom Domain Name on an Azure Web Site

Setting a Custom Domain Name on an Azure Web Site

I recently decided to add a custom domain name to a free Azure website that I use for development purposes. As the FREE Azure web site model doesn’t support custom domains (a shame but hard to complain as it’s FREE) I needed to upgrade the site to the ‘Shared’ mode. This is easily done by the Scaling button in the azure portal.

Firstly however I needed to link my current azure web site to sit under a different subscription to the one I used to set it up. The problem is that cannot move sites between subscription models yet (please fix this Microsoft). To get around this I needed to create a new website under the correct subscription and then publish my web site code to it. Luckily this is easy to do as it’s just a basic website but I can imagine that this could be painful if you have a bunch of storage accounts or a database to re-create.

Using the Azure Portal, creating a new site is a simple process Click +NEW at the bottom of the portal for the menu shown below:

image

Once created all I needed to do was download a Publish profile (see this tutorial link for how to publish to Azure) for the new site for Visual Studio to use. Once downloaded I opened my VS2012 solution and brought up the Publish dialog. I pointed it to the new Publish profile file and clicked Publish. In just a few seconds I’ve got a new Azure web site up and running with my existing MVC web application. This was very smooth, with no change to config or code required. The sheer simplicity of this impressed me as I was short on time.

Next I needed to allocate my custom domain which as previously mentioned is not available for FREE websites so i needed to upgrade to SHARED mode. From the Azure portal >web site configuration > scale > click SHARED (remember this model incurs a cost).

image

Once upgraded I could then immediately select DOMAINS and set up my CNAME and A record references, for more information see this useful link (configuring a custom domain name for a Windows Azure web site). It’s worth reading the comments on the post too as it covers issues with registering the domain without the WWW subdomain.

Once the DNS entries had propagated I had my existing site up and running under a custom domain running within a shared Azure instance, all with very little effort.

SQL Server Compact Minimum Date Value

Recently I got this error connecting to a SQL Server Compact database from .Net:

"An overflow occurred while converting to datetime."

SQLSo I dug into my data insertion code (I was using the excellent Massive mini ORM by the way – and yes I know its not really an ORM but that’s another post) and found I was setting the offending DateTime field to DateTime.MinValue which it turns out SQL Compact doesn’t like. After a bit of investigation I found that whilst .Net supports a minimum date (DateTime.MinValue) of "01/01/0001 00:00:00" and a maximum (DateTime.MaxValue) of "31/12/9999 23:59:59" SQL Compact’s minimum date is "01/01/1753 00:00:00" (the same as SQL Server 2005 and before). This is the same for all current versions of SQL Server compact. For SQL Server 2008 upwards (2008 R2 and 2012) it’s recommended to use the DateTime2 data-type which supports the same range of dates as .Net.

To summarise:

Version

Minimum Date

Maximum Date

.Net

All

01/01/0001 00:00:00

31/12/9999 23:59:59

SQL Server Compact

All

01/01/1753 00:00:00

31/12/9999 23:59:59

SQL Server
(using datetime)

All

01/01/1753 00:00:00

31/12/9999 23:59:59

SQL Server
(using datetime2)

2008 onwards

01/01/0001 00:00:00

31/12/9999 23:59:59

                          

For a handy guide to the SQL Compact datatypes see here : http://msdn.microsoft.com….

For SQL Server datatypes see here : http://msdn.microsoft.com…

The System.Data.SqlTypes namespace contains the useful SqlDateTime struct which has MinValue and MaxValue properties so you can safely use SqlDateTime.MinValue instead of DateTime.MinValue in your code. For more information on SqlDateTime see here.