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A while back I've introduced Sandboxable. It's a means to use NuGet packages that normally are not available for code that runs with Partial Trust.
In this post, we will walk through the steps to create a Microsoft Dynamics CRM plug-in that will add a message to an Azure queue.

A while back I’ve introduced . It’s a means to use NuGet packages that normally are not available for code that runs with Partial Trust.

In this post, we will walk through the steps to create a Microsoft Dynamics CRM plug-in that will add a message to an Azure queue.

At the end of the post you will find the links to the complete source code for you to use.

Setting up the project

  1. Create a new Class Library project in Visual Studio
  2. Add the following NuGet packages with their dependencies:
    • Microsoft.CrmSdk.CoreAssemblies
      This package will add the base to create a plug-in for CRM
    • MSBuild.ILMerge.Task
      This package makes sure that the generated assembly will also contain all dependencies.
      More information about this package can be found on the
    • Sandboxable.Microsoft.WindowsAzure.Storage
      This package provides the Azure storage SDK, modified to run in the sandbox.
  3. Change the Copy Local property for the CRM references to false. These assemblies are already present in the runtime hosting the sandbox, so they can be kept outside our assembly
  4. Enable strong name key signing on your project

Now you can do a test build of the project to check if everything works correctly.

Writing the plug-in

I’ve based the plug-in code on the MSDN article .

Getting the connection details

To connect to an Azure queue, you need 3 details

  1. The storage account name
  2. One of the storage account access keys
  3. The name of the queue

There are several ways to get these details at runtime. To name a few: hard-coded, stored as data in an entity, stored in a web resource as a XML file or in the plug-in step configuration.
For this sample we’ll use a JSON string stored in the secure storage property of the plug-in step.
To deserialize these settings we use JsonConvert with a nested PluginSettings class.

PluginSettings pluginSettings =
                     JsonConvert.DeserializeObject<PluginSettings>(this.secureString);

Initializing the CloudQueueClient

The offers an easy way to manage and use Azure queues.
To initialize this class, we need to provide the URL and the .

StorageCredentials storageCredentials =
               new StorageCredentials(pluginSettings.AccountName, pluginSettings.Key);

Uri baseUri = new Uri($"https://{pluginSettings.AccountName}.queue.core.windows.net");

CloudQueueClient queueClient = new CloudQueueClient(baseUri, storageCredentials);

Creating a reference to the queue

With the queue client, we can create a reference to the with the name that is stored in the constant named QueueName.
To make sure the queue exists, we call the which ensures us if there isn’t a queue present yet, it’ll be created for us at that moment.

CloudQueue queue = queueClient.GetQueueReference(QueueName);

queue.CreateIfNotExists();

Adding the message to the queue

We create some message data, using the context of the current plug-in execution. This data is wrapped in a .
We add the message to the queue, using the and we’re done!

var messageData = new
  {
    context.UserId,
    context.MessageName,
    entity.LogicalName,
    entity.Id,
    entity.Attributes
  };

CloudQueueMessage queueMessage =
                    new CloudQueueMessage(JsonConvert.SerializeObject(messageData));

queue.AddMessage(queueMessage);

We must build our project again so we can proceed.

Register the plug-in assembly

Now the freshly baked assembly needs to be registered on the server.
The steps to do this are outside the scope for this post but more information can be found in the .

Register the plug-in step for an event

To test the plug-in, we’ll register it on the creation event of the contact entity.
For performance optimization we’ll choose the asynchronous execution method. External resources should never be part of your synchronous pipeline.

In the Secure Configuration property, we set the value with the JSON object containing the connection information:

{
  "AccountName":"loremipsum",
  "Key":"DDWLOREM...IPSUMr0A=="
}

(obviously, these values do not represent real data)

Register the plug-in step for the creation event of contact entities

Testing the plug-in

We create a new contact in CRM called Sample User.
After a couple of seconds we see the following message appear on the queue:

{
  "UserId": "d617a1a0-359a-e411-9407-00155d0ae259",
  "MessageName": "Create",
  "LogicalName": "contact",
  "Id": "6e843a34-91b1-e611-80e4-00155d0a0b40",
  "Attributes": [
    {
      "Key": "firstname",
      "Value": "Sample"
    },
    {
      "Key": "lastname",
      "Value": "User"
    },
    {
      "Key": "fullname",
      "Value": "Sample User"
    },
    ...
  ]
}

(formatted for readability)

Concluding

By utilizing the Azure SDK, we only needed a few lines of code to send messages to an Azure queue and making all sorts of integration with other systems possible.
By using the Sandboxable project we’re no longer limited by the sandbox.

Sample code

The complete source code is available as sample project.
Expect more samples in the Sandboxable-Samples repository on GitHub in the future.

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I would like to introduce to you Winvision’s first open source project: Sandboxable.

Sandboxable enables your project to utilize functionality provided by other (Microsoft) libraries that normally are not available in a Partial Trust environment like the Microsoft Dynamics CRM sandbox process.
The project offers modified NuGet packages that will run with Partial Trust.

I would like to introduce to you ’s first open source project: .

Sandboxable enables your project to utilize functionality provided by other (Microsoft) libraries that normally are not able to use in a Partial Trust environment like the Microsoft Dynamics CRM sandbox process.
The project offers modified NuGet packages that will run with Partial Trust.

Sandboxing

Sandboxing is the practice of running code in a restricted security environment, which limits the access permissions granted to the code. For example, if you have a managed library from a source you do not completely trust, you should not run it as fully trusted. Instead, you should place the code in a sandbox that limits its permissions to those that you expect it to need.

You can read more on this in the article
If you encounter a .NET sandbox today chances are it’s running with

A big example of software running in a sandbox are the Microsoft Dynamics CRM (Online) Plug-ins and custom workflow activities. ()

The problem

As developers we use a lot of library code like NuGet packages as we’re not trying to reinvent the wheel. The downside is that most of these libraries are not written with a Partial Trust environment in mind.
When we embed these libraries to our code in the sandbox we encounter 2 common issues:

  1. The code contains security critical code and will fail to load with a TypeLoadException or will throw an SecurityException at runtime
  2. The package references another package that contains security critical code and even though the code might not even be used it will trigger one of the exceptions mentioned above

Problematic constructs

  • Calling native code
    [DllImport("advapi32.dll", SetLastError = true)]
    [return: MarshalAs(UnmanagedType.Bool)]
    internal static extern bool CryptDestroyHash(IntPtr hashHandle);
  • Override SecurityCritical properties of an object like Exception
    public override void GetObjectData(SerializationInfo info, StreamingContext context) {
        ...
    }

    Where Exception has the following attributes on this method

    [System.Security.SecurityCritical]
    public virtual void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        ...
    }
  • Serialize non-public classes, fields or properties
    [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore, NullValueHandling = NullValueHandling.Ignore, PropertyName = PropertyNotBefore, Required = Required.Default)]
    private long? _notBeforeUnixTime { get; set; }

The solution

When we encounter a NuGet package that fails to load or execute in the sandbox and it’s source is available we make a Sandboxable copy of it.
This is done by eliminating the offending code in a way that is the least obtrusive and publish this version to NuGet.

The base rules are:

  • Keep the code changes as small as possible
  • Prefix all namespaces with Sandboxable
  • Eliminate offending NuGet dependencies
  • If a new dependency is needed, it will be on a sandbox friendly NuGet package

Source and contribution

The source is published at the Sandboxable project at GitHub.

Included in the solution is also a stand-alone project to test if code will break inside a sandbox. This makes testing libraries easier without the need to deploy it to a (remote) environment.

I like to invite everybody to use the Sandboxable NuGet packages and contribute to the project.

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This week I’ll be attending the Microsoft Build 2016 conference in San Francisco.
Lots of news to be expected for developers covering the many technologies Microsoft is putting on the market.

This week I’ll be attending the Microsoft Build 2016 conference in San Francisco.
Lots of news to be expected for developers covering the many technologies Microsoft is putting on the market.

Keynotes

Traditionally there are 2 keynotes at the Build conference. The first one is focusing on Microsoft Windows. The second one is more focused on Microsoft Azure. I expect the same pattern this year.
Based on the news and rumors the last couple of weeks, combined with the scheduled sessions, I expect the following topics to be covered during the keynotess.

  • Windows 10
    Obviously. Redstone is coming and Edge is getting add-ins so those are 2 obvious topics. I expect an overview of all the new things that are already part of the current fast ring previews.
  • Xamarin
    Microsoft has recently bought the company. A move I already expected 2 years ago. And looking around San Francisco they’re running quite the marketing campaign. So naturally this needs to be in the keynote. I hope they’ll be answering the question how the licensing will be affected.
  • Xbox
    We are expecting universal apps on the Xbox for several years. But this year should be it. A tweet by Scott Hanselman indicates that Phil Spencer will be part of this years conference.
  • Surface Hub
    I don’t expect a new device, only some demo’s. But as the devices are now finally available for purchase they probably want to do some marketing around these costly beasts. Also a couple of sessions in the program are mentioning developing apps for this device.
  • Hololens
    The shipping of the first wave of devices is at the same time as the conference, that can’t be accidental. Lots of sessions are covering different aspects of the HoloLens. So a new demo during the keynote can’t be far away. Hopefully the device can measure the distance between the eyes automatically. Last year this was a manual task.
  • Visual Studio vNext
    A bit of news got around about the next version of Visual Studio and the improved installer experience. This would be the time to share this news officially.
  • .NET Core
    It’s about time the .NET core is officially released as it’s been in preview for a long time. So I expect the 1.0 RTM version to be pushed to the world today.
  • Azure
    Azure is a big platform, and I expect a couple of new features will be released to the public. Maybe even some Azure Stack integration will be demoed.
  • Office Graph
    Already announced in preview last year. I expect a full release this year. Maybe adding new features the API in previews.

My journey through the week

On my twitter feed I’ll be posting all the sessions I’m attending. My focus will probably be on UWP and Azure related sessions.

Want to meet me or do you have a question about the sessions I’ve attended? Just send me a message.

Watching sessions

Not in San Francisco and still want to be part of the action?
Channel9 will be covering a lot of content live including the Keynotes and interviews. Also all the sessions will be available later.

Go to the Channel9 Build 2016 website.