Tuesday, 29 September 2015

Generate Entity Framework update scripts from migrations

This is how you generate Entity Framework update scripts from migrations.

Note: this is a very simplified post that doesn't generate a very complicated database script.

So you already have an initial database migration in your project. If you don't go Google how to get started.

I'll start by generating an SQL script for my initial migration.

Here is part of my initial migration in C#:

I will now generate the script for this but running this command in the Package Manager Console:
Update-Database -Script -SourceMigration: $InitialDatabase -TargetMigration: Initial

Make sure you select the correct Default Project in the dropdown shown in the above picture.

Here is the SQL script:

Now I will update my model with a new property:

I then ran the following to create my new C# migration:
Add-Migration AddedAProperty -StartUpProjectName User.DbResourceAccess

Which created this new C# file:

Next I will run this:
Update-Database -Script -SourceMigration: $InitialDatabase -TargetMigration: AddedAProperty
Which created the following script:

You could then apply this to a production database for example.
I'm not sure you would want to insert into a __MigrationHistory table on production though.


Monday, 28 September 2015

Deployment considerations in Azure - Cloud Services

Manage Deployments in Azure

Note: this is a work in progress

Staging area is not designed to be a "QA" environment but only a holding-area before production is deployed.
You should open up a new service for Testing environment with its own Prod/Staging. In this case, you will want to maintain multiple configuration file sets, one set per deployment environment (Production, Testing, etc.)
Staging is a temporary deployment slot used mainly for no-downtime upgrades and ability to roll back an upgrade.
Azure provides production and staging environments within which you can create a service deployment. When a service is deployed to either the production or staging environments, a single public IP address, known as a virtual IP address (VIP), is assigned to the service in that environment. The VIP is used for all input endpoints associated with roles in the deployment. Even if the service has no input endpoints specified in the model, the VIP is still allocated and used as the source address assigned to outbound traffic coming from each role.

What happens when a service is promoted from staging to production?

Typically a service is deployed to the staging environment to test it before deploying the service to the production environment. When it is time to promote the service in staging to the production environment, you can do so without redeploying the service. This can be done by swapping the deployments.
The deployments can be swapped by calling the Swap Deployment Service Management API or by swapping the VIPs in the portal, which result in the same underlying operation on the hosted service. For more information on swapping the VIPs, see How to Manage Cloud Services.
Screen shot from Azure Portal - 2015-09-28

When the service is deployed, a VIP is assigned to the environment to which is it is deployed. In the case of the production environment, the service can be accessed by the URL,, or by the VIP. When a service is deployed to the staging environment, a VIP is assigned to the staging environment and the service can be accessed by a URL,, or by the assigned VIP. The assigned VIPs can be viewed in the portal or by calling the Get Deployment Service Management API.
When the service is promoted to production, the VIP and URL that were assigned to the production environment are assigned to the deployment that is currently in the staging environment, thus “promoting” the service to production. The VIP and URL assigned to the staging environment are assigned to the deployment that was in the production environment.
It is important to remember that neither the production public IP address nor the service URL changes during the promotion.
To examine how this works, we can illustrate a scenario in which there is a Deployment A deployed to the production environment. Additionally, there is a Deployment B deployed to the staging environment. The following table illustrates VIPs after the initial deployment of the services to production and staging:


Deployment A
Deployment B
Once the Deployment B is promoted to production the VIPs are as follows:
Deployment B
Deployment A
When the deployments are swapped, the deployment in the production environment that was associated with the production VIP and URL is now associated with the staging VIP. Likewise, the deployment in the staging environment that was associated with the staging VIP and URL is now associated with the production VIP.

Only new incoming connections are connected to the newly promoted service. Existing connections are not swapped during a deployment swap.

Persistence of VIPs in Windows Azure

Throughout the lifetime of a deployment, the VIP assigned will not change, regardless of the operations on the deployment, including updates, reboots, and reimaging the OS. The VIP for a given deployment will persist until that deployment is deleted. When a customer swaps the VIP between a stage and production deployment in a single hosted service, both deployment VIPs are persisted. A VIP is associated with the deployment and not the hosted service. When a deployment is deleted, the VIP associated with that deployment will return to the pool and be re-assigned accordingly, even if the hosted service is not deleted. Windows Azure currently does not support a customer reserving a VIP outside of the lifetime of a deployment.

Managing ASP.NET machine keys for IIS

Azure automatically manages the ASP.NET machineKey for services deployed using IIS. If you routinely use the VIP Swap deployment strategy, you should manually configure the ASP.NET machine keys. For information on configuring the machine key, see Configuring Machine Keys in IIS 7.

More on machine keys later ...

Questions for later:

Is there any way to deploy different instance sizes for test/production

Note that the image above shows multiple cscfg files, but only one csdef file. The cscfg file has the role names, instance counts, configuration values, and so on. The one csdef file is used with whichever configuration you select when you publish. It has a list of all of the configuration settings (but not the values), setup tasks (if applicable), the size of the VM to be used, and so on. The value you want to especially note is the VM size.

Using this methodology of multiple configuration files in one cloud project, you only have one place to set the size of the VM regardless of whether you are publishing to staging or production. You may not want to use the same sizes for staging and production, especially if you are using medium or larger VMs in production and small VMs in staging. In that case, you either have to change this every time you publish, or you have to have another solution.

Note: See the heading "Multiple cloud projects with their own configuration settings":

Friday, 18 September 2015

See your Azure VM deployment succeed or fail!


Yesterday we were having deployment issues due to an Azure WebRole startup task (more on that in my next post.)

We rolled back the changes and all was fine but I wanted to find the information that was logged on the server so I can trouble shoot in the future if it happens again. 

I just did a fresh deployment as a base line to prove that I was working with a successful deployment.

As it was deploying I could see log records appearing in here when logged onto my Cloud Service VM:

As this was a successful deployment I could see messages in the above mentioned Windows Azure Event log showing that nothing went wrong.

I could see the log message stating that the web site installed into IIS successfully.
I could see the successful OnStart() and OnRun() events.

Here are some screen shots:

Note that if we had diagnostics turned on we could probably see the same information inside the visual studio server explorer for our cloud service.

Not very useful when everything goes well. Ill post more when and if I get a failed deployment.


Tuesday, 30 June 2015

An alternative Way to Remotely Debug Azure Web Sites


I have been having trouble connecting to my Azure instances with the normal attach to debugger method:

This never works for me even when debugging in enabled.

Here is a link to a way that works and it worked the first time.

I only tested with an Azure Web App so not sure about WCF and services yet.
(More on this later)


Thursday, 9 April 2015

Stop an AzureVM using Azure Automation with a schedule


UPDATE: The script mentioned in this post is now here:

In this blog I will show you how to use Azure Automation to schedule a Powershell script to stop and deallocate a VM running in Azure. 

The reason I am blogging this is because I have spent a couple of days looking at other people's blogs and the information seems to not be quite correct. In particular, the need to use a self signed certificate from your Azure box is no longer required.

The reason you might want to do this is to save some money as when your Azure VM is stopped and deallocated, you will not be charged for it.

Firstly, I created a VM to play with called tempVMToStop as follows:

It required a username and password so I used my name. 

Once you have the VM you can remote desktop to it using the link at the bottom of the Azure portal and the username and password created in the previous step.

The next step is to add our automation script.

Now we go to automation in Azure:

Remember the goal of this blog is to automatically stop the following VM:
first we will need to create a user that is allowed to run our automation in Azure Active Directory as shown here:

Create the user to be used for automation:

Then go back into the automation section and choose Assets:

and add the automation user you just created here:

This is reasonably new as before you needed to create a self signed certificate on your VM and import the pfx file into an Asset => Credential but this is no longer needed.

Now go to the automationDemo and then choose Runbooks:

Click to create a new runbook:

Once it is created click on Author and write your script as follows:
workflow tempVMToStopRunBook

    # Specify Azure Subscription Name
    $subName = 'XXX- Base Visual Studio Premium with MSDN' 
    $cred = Get-AutomationPSCredential -Name "automationuser"
    Add-AzureAccount -Credential $cred
    Select-AzureSubscription -SubscriptionName $subName 

    $vm = Get-AzureVM -ServiceName $cloudServiceName -Name $vmName 
    Write-Output "VM NAME: $vm"
    Write-Output "vm.InstanceStatus: $vm.InstanceStatus"
    if $vm.InstanceStatus -eq 'ReadyRole' ) {
        Stop-AzureVM -ServiceName $vm.ServiceName -Name $vm.Name -Force    


Note that the subscriptionname shown as  XXX - Base Visual Studio Premium with MSDN will need to be replaced by your subscription.

Also the workflow class name must be the same as the runbook name.

Save it and then you can choose to test it or just publish it. 
I will skip to publish as I have already tested it.

Once it is published you can click start and enter the 2 param names that the script is expecting:



Now we want to see that our VM stops so here was mine before:

Once you run it you will see some output when you click Jobs in the runbook:

And then if you look back at your VM it should be stopped:

Note that as we are totally deallocating the resources, the next time you start it up, it will get an new IP address but this will be all given to you in the VM section in your portal.

The next step is to obviously schedule what we just did and also schedule a start script so we could, for example, stop our VM at the end of a business day and start it in the morning at 8am so it is ready for us to use. 

This will save some money as the VM will not be using resources overnight.

Go back to the root of your automation and add a new asset for your schedule:

Here's one I created that will run the Power Shell script we created every day:

That's all there is to it. 

Note that I am no expert on Azure automation so all comments and constructive criticism are welcome.


Wednesday, 1 April 2015

Debugging an custom object using Powershell in the Package Manager Console window.


I was just trying to find out what data my collection of custom objects was getting hydrated with. the context doesn't matter but for the record, I was hitting a Sitecore index and duplicates were being rendered in my UI.

I started using the immediate window but it had limitations that were preventing me from getting what I needed.

I wanted to see if all the objects that were hydrated that contained the word "test" hence the "test*".

Anyway, here is what I came up with:

for($i = 0; $i -lt 1000; $i++) // 1000 is a bit high so adjust for your needs
$a = $dte.Debugger.GetExpression("(()results[$i]).Name"); 

if ($a.Value -match "test*") 
Write-Host $a.Value 

Here are the results:

  • "testcampaignspeed73" 
  • "testcampaignspeed74"
  • "testcampaignspeed2"
  • "testcampaignspeed23"

And here is the PMC window:

I just wanted to put this out there for myself to remember and for anyone else who needs it.