Category Archives: Azure

Production Tips for ASP .NET Core 3.1 Web Apps

By Shahed C on April 20, 2020
5 Replies

This is the sixteenth of a new series of posts on ASP .NET Core 3.1 for 2020. In this series, we’ll cover 26 topics over a span of 26 weeks from January through June 2020, titled ASP .NET Core A-Z! To differentiate from the 2019 series, the 2020 series will mostly focus on a growing single codebase (NetLearner!) instead of new unrelated code snippets week.

Previous post:

NetLearner on GitHub:

In this Article:

P is for Production Tips

After getting through more than halfway in this A-Z series, this blog post takes a step back from application code to focus on productions tips. Once you’re ready to deploy (and maintain) your web app in production, there are many tips and tricks you should be aware of. In fact, feel free to discuss with your team members and the dev community to learn about other ways developers are deploying in production.

Server Environments from Dev to Prod via Staging
Server Environments from Dev to Prod via Staging

While this article focuses on deployments to Azure App Service, you can use some of the lessons learned for your own environments. That being said, I would highly recommend taking a look at Azure for all your staging and production deployment needs.

Deployment Slots

Azure makes it very easy to deploy your ASP .NET Core web application with the use of Deployment Slots. Instead of publish a web app directly to production or worrying about downtime, you can publish to a Staging Slot and the perform a “swap” operation to essentially promote your Staging environment into Production.

NOTE: To enable multiple deployment slots in Azure, you must be using an App Service in a Standard, Premium, or Isolated tier.

If you need help creating a Web App in App Service, you may refer to my blog post on the topic:

To make use of deployment slots for your Web App:

  1. Log in to the Azure Portal.
  2. Create a new Web App if you haven’t done so already.
  3. Locate the App Service blade for your Web App
  4. Enter the Deployment Slots item under Deployment
  5. Click + Add Slot to add a new slot
  6. Enter a Name, chose a source to clone settings (or not)
  7. Click the Add button to create a new slot
Deployment Slots in Azure App Service
Deployment Slots in Azure App Service

Once you set up multiple slots for staging and production, you may use the Swap feature to swap your deployed application when the staged deployment is ready to be deployed into production. Note that all slots are immediately live at the specified endpoints, e.g. hostname.azurewebsite.net.

You may also adjust website traffic by setting the Traffic % manually. From the above screenshot, you can see that the Traffic % is initially set to 0 for the newly-created slot. This forces all customer traffic to go to the Production slot by default.

When deploying your application through various means (Visual Studio Publish, Azure CLI, CI/CD from your Source Control System, etc), you may choose the exact slot when there is more than one. You may also set up “Auto-Swap” to swap a slot (e.g. staging) automatically into production, upon pushing code into that slot.

To learn more about all of the above, check out the official docs at:

Environment Configuration

To maintain unique configuration settings for each environment (e.g. staging database vs production database connection strings), you should have unique configuration settings for each environment. This is easily accomplished using the Configuration section in the Settings category of each slot’s unique blade.

Configuration screen in Azure App Service
Configuration screen in Azure App Service

NOTE: If you need help with User Secrets for your development environment or Key Vault secrets for your server environment, consider the following posts from my 2018 series and earlier in this 2020 series:

EF Core Migrations

You may be wondering how you can deploy structural changes from your database into production. Perhaps, you write manual SQL scripts to run in production, maybe you use a tool to generate such SQL scripts or a combination of both. Many developers aren’t aware but you can actually make use of Entity Framework Core (EF Core) Migrations to update your database structure.

To get a quick refresher on EF Core Migrations and Relationships, check out the following post:

You wouldn’t typically run your “Update Database” command in production. Instead, you could generate a SQL Script from your EF Core Migrations. This will allow you to inspect the SQL Scripts (revise them if necessary), hand them over to a DBA if appropriate and finally run the SQL Scripts in production when required.

The following PowerShell command can be run in Visual Studio’s Package Manager Console panel:

Script-Migration

The following CLI Command can be run on a Command Prompt, PowerShell prompt or VS Code Terminal window:

dotnet ef migrations script

You may set specific migrations to start from and/or end on:

Script-Migration -To <starting-migration>
Script-Migration -From <ending-migration>

You may also dump out the SQL scripts into a file for further inspection:

Script-Migration -Output "myMigrations.sql"

Scalability

If you’re deploying your web apps to Azure App Service, it’s a no-brainer to take advantage of scalability features. You could ask Azure to scale your app in various ways:

  • Scale Up: Upgrade to a more powerful (and higher priced) tier to add more CPU, memory and disk space. As you’ve seen with the appearance of staging slots, upgrading to a higher tier also provides additional features. Other features include custom domains (as opposed to just subdomains under azurewebsites.net) and custom certificates.
  • Scale Out: Upgrade the number of VM instances that power your web app. Depending on your pricing tier, you can “scale out” your web app to dozens of instances.
  • Autoscaling: When scaling out, you can choose when to scale out automatically:
    • Based on a Metric: CPU %, Memory %, Disk Queue Length, Http Queue Length, Data In and Data Out.
    • Up to a specific Instance Count: set a numeric value for the number of instances, set minmium and maximum.

An example of autoscaling on a metric could be: “When the CPU% is >50%, increase instance count by 1“. When you had new scaling conditions, you may also set a schedule to start/end on specific dates and also repeated on specific days of the week.

Adding a Scale Rule to Scale Out in Azure App Service
Adding a Scale Rule to Scale Out in Azure App Service

NOTE: In order to make use of Auto-Scaling, you’ll have to upgrade to the appropriate tier to do so. You can still use Manual Scaling at a lower tier. Scalability features are not available on the F1 Free Tier.

CI/CD

There are countless possibilities to make use of CI/CD (Continuous Integration and Continuous Deployment) to make sure that your code has been merged properly, with unit tests passing and deployed into the appropriate server environments. Some of your options may include one of the following: Azure Pipelines, GitHub Actions, or some other 3rd party solution.

  • Azure Pipelines: an offering of Azure DevOps services, you can quickly set up CI/CD for your web app, both public and private.
  • GitHub Actions: available via GitHub, the relatively-new Actions feature allows you to automate your workflow

The Deployment Center feature in Azure’s App Service makes it very easy to select Azure Pipelines (under Azure Repos) for your web app. This is all part of Azure DevOps Services, formerly known as VSTS (Visual Studio Team Services)

Deployment Center in Azure App Service
Deployment Center in Azure App Service

To get started with the above options, check out the official docs at:

TeamCity and Octopus Deploy are also popular products in various developer communities. Whatever you end up using, make sure you and your team select the option that works best for you, to ensure that you have your CI/CD pipeline set up as early as possible.

Troubleshooting

Once your application has been deployed, you may need to troubleshoot issues that occur in Production. You can use a combination of techniques, including (but not limited to) Logging, Error Handling and Application Insights.

  • Logging: From ASP .NET Core’s built-in logging provider to customizable structured logging solutions (such as Serilog), logging helps you track down bugs in any environment.
  • Error Handling: Anticipating errors before they occur, and then logging errors in production help you
  • Application Insights: Enabled by default in Azure’s App Service, Application Insights literally give you insight into your web application running in a cloud environment.

For more information on Logging and Error Handling, check out the earlier posts in this series:

For more information on Application Insights, check out the official documentation at:

References

Organizational Accounts for ASP .NET Core 3.1

By Shahed C on April 13, 2020
5 Replies

This is the fifteenth of a new series of posts on ASP .NET Core 3.1 for 2020. In this series, we’ll cover 26 topics over a span of 26 weeks from January through June 2020, titled ASP .NET Core A-Z! To differentiate from the 2019 series, the 2020 series will mostly focus on a growing single codebase (NetLearner!) instead of new unrelated code snippets week.

Previous post:

NetLearner on GitHub:

NOTE: The NetLearner suite of apps won’t be updated to use organizational authentication in the main branch, so you can check out the new sample code in the experimental subfolder, merged from a branch:

In this Article:

O is for Organizational Accounts

If you’ve created new ASP .NET Core projects, you’ve probably seen an option to add authentication upon creation. In Visual Studio, the IDE provides radio buttons to select a specific type of Authentication. Using CLI commands (e.g. in the VS Code terminal) you can use the ‐‐auth flag to choose the type of authentication you’d like to add.

The possible values are:

  • None – No authentication (Default).
  • Individual – Individual authentication (accounts stored in-app).
  • IndividualB2C – Individual authentication with Azure AD B2C.
  • SingleOrg – Organizational authentication for a single tenant.
  • MultiOrg – Organizational authentication for multiple tenants.
  • Windows – Windows authentication..

In this article, we will focus on the option for Work or School Accounts. This option can be used to authenticate users with AD (Active Directory, Azure AD or Office 365. This authentication process is illustrated in the diagram shown below:

ASP .NET Core web authentication via AzureAD
ASP .NET Core web authentication via AzureAD

Adding Authentication

To add authentication to a new project quickly, here are the instructions for Visual Studio 2019.

If you choose to use the new splash screen:

  1. Click “Create a new project”
  2. Select “ASP .NET Core Web Application” or “Blazor” (server-side)
  3. Click Next
  4. Enter Project Name, Location, Solution Name
  5. Optional: check the checkbox to place in the same directory
  6. Click Create
  7. Select .NET Core and then ASP .NET Core 3.1 from dropdowns
  8. Select a project type, e.g. Empty, Web Application (Razor Pages or MVC), Blazor App.
  9. Click the “Change” action link in the Authentication section
Creating a new web app project with authentication
Creating a new web app project with authentication

This should allow you to change the authentication type to “Work or School Accounts” so that you may your organizational domain info. As always, you may select the little info buttons (lowercase i) to learn more about each field. Talk to your system administrator if you need more help on what domains to use.

Work/School account selected for authentication method

NOTE: If you need help creating new .NET Core 3.1 project types in Visual Studio, take a look at this previous blog post in this series on .NET Core 3.0 to get some help on how to enable it.

If you wish to skip the Splash Screen instead upon launching VS2019:

  1. Click “Continue without code” in the lower right area of the splash screen.
  2. In the top menu, click File | New | Project (or Ctrl-Shift-N)
  3. Follow the remaining steps outlined earlier in this section

To use CLI Commands in a Terminal window, use the dotnet new command followed by the ‐‐auth flag. The authentication type can be any of the aforementioned authentication types, e.g. Individual.

dotnet new mvc --auth Individual -o myproj

Configuring App Registration

If you’ve used “Individual User Accounts” before, you’ve probably used a database to store user data, either on-premises or in the cloud. If you’ve used “Work or School Accounts” (i.e. organizational accounts), you may have the old App portal at the following URL:

Old App Registration Portal
Old App Registration Portal

On the old site, you may see a message suggesting that you should go to the Azure Portal to use the newer (current) App Registrations feature. This feature was previously in preview, and you can currently use it directly in the Azure Portal. If you click the link from the old site, it should take you directly to the App Registrations page, and may prompt you to log in first.

TODO: screenshot of new (preview?) portal, overview section
App Registration screen showing overview

If you’re not clear about how you got to this screen or how to come back to it later, here’s a set of steps that may help.

  1. Log in to the Azure Portal
  2. Search for App Registrations
  3. Arrive at the App Registrations page
  4. When a newer preview version becomes available, you may have to click the banner that takes you to a preview experience.
New App Registration in Azure Portal
New App Registration in Azure Portal

In the form that follows, fill out the values for:

  • Name (which you can change later)
  • Account Type (your org, any org, any org + personal MSA)
  • Redirect URI (where users will return after authentication)
authentication
Register an application for authentication

Now you should have options to configure your app and also download a pre-written application to get started. In the QuickStart section for your newly registered application (after selecting  the guide for “ASP .NET Core”, you should see a button to make the changes for you and also download a configured Visual Studio application.

Quickstart screen for app registration
Quickstart screen for app registration

In the steps that follow:

  1. Click the “Make the changes for me” button to make the necessary configuration changes.
  2. Optional: Click the “Download” link to download the pre-configured Visual Studio solution, if you don’t already have a project.

At the time of this writing, the downloadable sample project is a VS2019 application for ASP .NET Core 2.2. You can download it to inspect it, but I would recommend creating a new project manually in VS2019. There may be some subtle differences between projects created by VS2019 with authentication turned on, versus what you get with the downloaded project.

For further customization using the Manifest file available to you, check out the official documentation on the Azure AD app manifest:

Using Authentication in Your Code

When creating a new project in VS2019, you get the following lines of code in your ConfigureServices() method, including calls to .AddAuthentication(). For different project types (MVC, Razor Pages, Blazor), you should also see some additional code setting up the authorization policy. 

// contents of ConfigureServices() when created in VS2019

services.AddAuthentication(AzureADDefaults.AuthenticationScheme)
.AddAzureAD(options => Configuration.Bind("AzureAd", options));

The string value “AzureAd” is referenced in your appsettings file, e.g. appsettings.json in MVC, Razor Pages, or Blazor projects. The properties for this entry include the following:

  • Instance: URL for login page, e.g. https://login.microsoftonline.com
  • Domain: your AD tenant’s domain, e.g. microsoft.onmicrosoft.com
  • TenantId: your Tenant Id value, usually a GUID
  • ClientId: Your app’s Client Id, obtained from app registration
  • Callback Path: partial path for sign-in, e.g. /signin-oidc 
{
  "AzureAd": {
    "Instance": "https://login.microsoftonline.com/",
    "Domain": "<REPLACE_DOMAIN_NAME>",
    "TenantId": "<REPLACE_TENANT_ID>",
    "ClientId": "<REPLACE_CLIENT_ID>",
    "CallbackPath": "/signin-oidc"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "AllowedHosts": "*"
}

You can see more information on appsettings.json values in the official docs. You can also open the apssettings.json from the portal-downloaded project to get your own app’s Id values. The following documentation is specifically written for v2, but offers explains for important fields such as ClientId and TenantId.

To get a refresher on Authentication and Authorization in ASP .NET Core 3.1, check out the following post on from earlier in this blog series.

For more on assigning users to specific roles, check out the official documentation at the following URL:

Finally, take a look at the Login.partial.cshtml partial view to observe the way a user’s identity is detected and shown in an MVC or Razor Pages web app. Here is a snippet from the samples:

@if (User.Identity.IsAuthenticated)
{
 <li class="nav-item">
 <span class="nav-text text-dark">Hello @User.Identity.Name!</span>
 </li>
...
}

NOTE: The Blazor web app wraps the authorized content in an <Authorized> tag within an <AuthorizedView. For more on the Blazor project, take a look at the Blazor post:

Depending on what you have access to, the User.Identity object may not contain everything you expect it to. Here are some things to take note of:

  • User.Identity should be null when not logged in
  • User.Identity should be non-null when logged in…
  • … however, User.Identity.Name may be null even when logged in
  • If User.Identity.Name is null, also check User.Identity.Claims
  • User.Identity.Claims should have more than 0 values when logged in

The following screenshot shows an example of the user information in my debugging environment when logged in:

User.Identity.Name with Claims in debugger
User.Identity.Name with Claims in debugger

Running the Samples

Running the sample web projects should redirect you to the Azure AD login page for your tenant. The login page should look identical for all 3 project types: MVC, Razor Pages or Blazor. If you’ve already logged in to one or more accounts in your browser, you should have one or more identities to select from.

Once you’ve selected an account, you should see a confirmation screen (at least the first time) to Accept the authentication and login. This screen will look similar for all your projects, and the project name should be displayed in the middle.

MVC app authentication confirmation
MVC app authentication confirmation
Razor Pages app authentication confirmation
Blazor app authentication confirmation
Blazor app authentication confirmation

Finally, you should see each web application with some indication that you are currently logged in. In the template-generated sample apps, this is demonstrated by the “Hello” message in the header area.

MVC web app, logged in
MVC web app, logged in
Razor Pages web app, logged in
Razor Pages web app, logged in
Blazor web app, logged in
Blazor web app, logged in

References

.NET 5.0, VS2019 Preview and C# 9.0 for ASP .NET Core developers

By Shahed C on April 6, 2020
3 Replies

This is the fourteenth of a new series of posts on ASP .NET Core 3.1 for 2020. In this series, we’ll cover 26 topics over a span of 26 weeks from January through June 2020, titled ASP .NET Core A-Z! To differentiate from the 2019 series, the 2020 series will mostly focus on a growing single codebase (NetLearner!) instead of new unrelated code snippets week.

Previous post:

NetLearner on GitHub:

NOTE: The NetLearner suite of apps won’t be updated to .NET 5.0 at this time, so you can check out the new template-generated projects in an experimental subfolder:

In this Article:

N is for .NET 5.0, VS2019 Preview and C# 9.0

As we have crossed the halfway point in this series, now is a good time to take a step back and look forward at .NET 5.0. This is the next iteration of .NET Core, which skips over the number 4, and unifies all flavors of .NET into a single .NET (i.e. .NET Core, .NET Framework and Mono).

In order to use .NET 5.0 (Preview 2 as of this writing), we need to install Visual Studio 2019 v16.6.0 Preview 2.1. This will give you access to all the latest (preview) project templates for ASP .NET Core 5.0. Since C# 9.0 is still early in development, we will just briefly touch on upcoming/proposed language features.

Visual Studio 2019 Preview

Visual Studio 2019 has been out since early 2019, so you can grab the latest stable version from the main download page. Visit any of the URLs below to select the edition you need:

In order to get the latest Preview version, you must visit the special download page for Previews:

As before, the Community Edition (comparable to Pro) is free for students, open-source contributors and individuals. The Pro and Enterprise editions add additional products and services from small teams to enterprise companies.

But wait! What if you can’t stay online for the length of the installation or need to reinstall quickly at a later date? If you need an offline installer, check out the instructions on the following page:

What are some cool new and improved features to be aware of? There are so many that I stitched together a series of tweets from Amanda Silver (CVP of Product for Developer Tools) and created the following thread in April 2019:

The aforementioned thread highlights the following features. Click each hyperlink in the list below for more info on each.

  • Live Share: Available as an extension in VS Code, Live Share is installed by default with VS2019. Easily collaborate with other developers while coding in real-time!
  • Intellicode: Use AI to write better code. Choose to share what you want with others or keep things private.
  • Git-first workflows: Choose to create a new project from a source code repo or use a template. The new start window provides more options up front.
  • Debug search: Search while debugging. Type in search filters in the Watch, Locals, and Autos panels.
  • Snapshot debugging: Available in the Enterprise Edition, snapshot debugging allows you to get a snapshot of your app’s execution after deployment. This includes cloud deployments, Azure VMs and Kubernetes containers.
  • VS Search: Dynamic search results include commands, menus, components and templates. Note that this was formerly know as Quick Launch.
  • App Service Debugging: Attach the debugger to your app running in Azure App Service!
  • App Service Connectivity: Connect your web app to Azure App Service with ease, including App Insights monitoring.
  • Azure Monitor: Use Azure Monitor to get additional insight on your deployed app!

If you prefer to sit back and relax and just watch a recap of the launch announcements, I put together a handy list of YouTube videos from the VS2019 launch event. This playlist kicks off with the 50-minute keynote, is followed by a string of videos and ends with a cumulative 7-hour video if you prefer to watch all at once.

So, what’s new in the latest version of Visual Studio 2019 v16.6 Preview 2?

  • Version Control: improved Git functionality, including quicker GitHub hosting with a single-click
  • Snapshot Debugging: improved Snapshot Debugger experience, without requiring a restart when using Snapshot Debugger with Azure App Service
  • .NET Async: new .NET Async tool (included with Performance Profiler) to help with better understanding and also optimizing your async/await code
  • JavaScript/TypeScript Debugging: improved JS/TS debugger, with support for debugging service workers, web workers, iframes and in-page JS.
  • .NET Productivity: multiple features for .NET developers including help for the following:
    • add an explicit cast (when an implicit cast isn’t possible),
    • add a “file banner” across one or more code files,
    • refactor/simply conditional expressions,
    • convert regular string literals to verbatim strings

The list of features above is just a summary of the official announcement. For details on each of these features, check out the official announcement at:

.NET 5.0 Preview 2

To get started, start with the latest version of .NET 5.0:

If you’ve already installed Visual Studio 2019, you may have followed the following steps:

  1. Download Visual Studio 2019 Preview
  2. Click File | New | Project (or create new from splash screen)
  3. Create a new ASP .NET Core Web App
  4. Select .NET Core and then ASP .NET Core 5.0 as the project type/platform

NOTE: For previous versions of .NET Core, you may not have seen an option for ASP .NET Core 3.0 in the list of project templates after installing VS2019. When ASP .NET Core 3.0 was still in preview as of April 2019 (even after the release of Visual Studio 2019), it was not automatically available for selection. In order to create ASP .NET Core 3.0 projects with VS2019, you would have had to install .NET Core 3.0 and enable previews of the .NET Core SDK in Visual Studio’s Options panel.

In Visual Studio 2019 Preview, this additional step isn’t necessary for ASP .NET Core 5.0. In fact, the Options panel includes settings for ASP .NET Core, without any mention of enabling preview versions.

VS2019 Options panel
VS2019 Options panel

C# 9.0 Features

To see what’s to come in C# 9.0, check out the official list of milestones on GitHub, specifically Milestone 15 for C# 9.0:

There are already dozens of feature candidates for the C# 9.0 release. The list includes Records and Pattern-Based “With” Expressions. From the official proposal, “Records are a new, simplified declaration form for C# class and struct types that combine the benefits of a number of simpler features“.

This new feature allows you to omit an argument for its corresponding optional parameter, when invoking a function member. In this case, the value of the receiver’s member is implicitly passed. This is accomplished in by the use of a “with-expression” and the use of this.SomeIdentifier to set a default argument.

Here is an example of what that could look like:

class TwitterUser
{
    public readonly int Followers;
    public readonly int Following;
    public TwitterUser With(
        int followers = this.Followers, 
        int following = this.Following) 
            => new TwitterUser(followers, following);

}

How would you use this so-called “caller-receiver default argument?

TwitterUser twitterUser1 = new TwitterUser(1000, 2000)
TwitterUser twitterUser2 = twitterUser1.With(followers: 0);

The above code creates a new TwitterUser, using the existing object to copy its values but changes the number of followers. For more information about the Records feature, check out the official proposal with detailed notes and code samples:

NOTE: To ensure that C# 9.0 preview features are available when a preview version becomes available, you can set the LangVersion property explicitly for your project. This setting is buried deep inside your Advanced settings within your project’s Build tab.

To update the language setting (after a future preview release):

  1. Right-click your project in Solution Explorer.
  2. Select Properties to view your project properties.
  3. Click the Build tab within your project properties.
  4. Click the Advanced button on the lower right.
  5. Select the appropriate Language version, e.g. C# 9.0 (beta)
  6. Optional: you may select “unsupported preview…” instead

If you try the above steps with VS2019 v16.6.0 Preview 2 (as of this writing), the language version selection is not available at this time. For more information on C# language versioning, check out the official documentation at:

C# Language Version Selection
C# Language Version Selection

The above screenshot shows the aforementioned setting in the Visual Studio UI. If you wish to update your .csproj file directly, you may view/edit the <LangVersion> value. A few samples are shown below:

For a .NET Core 3.0 console app set to use C# preview versions, the value of <LangVersion> is set to the value “preview”. This may be subject to change for C# 9 when it is released. 

<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
      <OutputType>Exe</OutputType>
      <TargetFramework>netcoreapp3.0</TargetFramework>
      <LangVersion>preview</LangVersion>
   </PropertyGroup>
</Project>

For a .NET Core 3.0 console app set to use C# 8.0 explicitly before its release, the value of <LangVersion> was set to the value “8.0”. Once again, this may be subject to change for C# 9. 

<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
      <OutputType>Exe</OutputType>
      <TargetFramework>netcoreapp3.0</TargetFramework>
      <LangVersion>8.0</LangVersion>
   </PropertyGroup>
</Project>

ASP .NET Core 5.0 Project Types

When you create a new .NET 5.0 web project with Visual Studio 2019, you’ll see some familiar project types. You will also see some new project types. These are shown in the 2 screenshots below:

List of ASP .NET Core 5.0 projects
List of ASP .NET Core 5.0 projects
List of ASP .NET Core 5.0 projects (continued)
List of ASP .NET Core 5.0 projects (continued)

The above project types are described below:

  1. Empty: familiar empty project that just writes out Hello World to the HTTP Response, without the use of MVC or Razor Pages
  2. API: familiar project type for creating Web APIs and RESTful services. Can be mixed and matched with Razor Pages or MVC components.
  3. Web Application: familiar project type for creating Web Apps with Razor Pages. Can be mixed and matched with Web API and/or MVC components.
  4. Web Application (MVC): familiar project type for creating Web Apps with MVC application structure. Can be mixed and matched with Razor Pages and/or Web API.
  5. Angular, React.js, React.js and Redux: familiar web projects for web developers who wish to build a JavaScript front-end, typically with a Web API backend.

FYI, the following project templates have moved out of their original location (inside ASP .NET Core web apps):

  • gRPC Service: allows creation of a new gRPC service to make use of Google’s high-performance Remote Procedure Call (RPC) framework
  • Worker Service: allows creation of background processes, e.g. Windows services or Linux daemons.
  • Razor Class Library: allows creation of reusable UI Class Libraries with Razor Pages. See previous post on Razor Class Libraries.

Blazor’s server-side project template can also be found at the root-level of the template list, under Blazor App.

List of ASP .NET Core 5.0 projects (Blazor Server)
List of ASP .NET Core 5.0 projects (Blazor Server)

Well, what about client-side Blazor? You may have noticed that server-side Blazor (aka Razor Components are mentioned, but there is no sign of client-side Blazor. As of March 2020, client-side Blazor running in the browser with WebAssembly is still in preview (v3.2.0 Preview 3).

If you were to install the latest .NET Core 3.1 SDK, you would also have to download the latest Blazor WebAssembly separately.

In order to install the client-side template from a command line, run the following command:

dotnet new -i Microsoft.AspNetCore.Components.WebAssembly.Templates::3.2.0-preview2.20160.5

NOTE: Installing VS2019 v16.6 Preview 2 automatically installs an updated version of the .NET Core 3.1 SDK. This version includes the latest Blazor WebAssembly template. This means that a manual installation of client-side Blazor is not required when using this preview version of Visual Studio. However, you would have to select .NET Core 3.1 after selecting Blazor, if you wish to select the latest client-side Blazor WebAssembly template in VS2019 v16.6 Preview 2.

Blazor templates in VS2019 Preview
Blazor templates in VS2019 Preview

On a related note, check out my previous post on server-side Blazor:

Migrating from 3.1 to 5.0

With all this goodness on the roadmap, you may be wondering how you can start migrating your ASP .NET Core 3.1 projects to .NET 5.0. Fear not, the official guide (a work in progress) is now available:

This documented migration process involves the following steps:

  1. Update .NET Core SDK version in global.json (from “3.1.200” to “5.0.100-preview.2.20176.6”)
  2. Update the target framework (from netcoreapp3.1 to netcoreapp5.0)
  3. Update package references (e.g. from “3.1.2” to “5.0.0-preview.2.20167.3”)
  4. Update Docker images to include a base image that includes ASP .NET Core 5.0 (e.g. by using the docker pull command followed by mcr.microsoft.com/dotnet/core/aspnet:5.0)
  5. Review breaking changes: refer to https://docs.microsoft.com/en-us/dotnet/core/compatibility/3.1-5.0

To deploy a .NET 5 project via Azure DevOps, try the following YAML

steps:
- task: UseDotNet@2
  inputs:
    packageType: sdk
    version: 5.0.100-preview.2.20176.6
    installationPath: $(Agent.ToolsDirectory)/dotnet

The above YAML snippet is a suggestion from .NET developer Neville Nazerane via the unofficial ASP .NET Core Facebook group:

NOTE: ASP .NET Core in .NET 5.0 Preview 2 only includes minor bug fixes (but not any major new features).

References

Key Vault for ASP .NET Core 3.1 Web Apps

By Shahed C on March 16, 2020
5 Replies

This is the eleventh of a new series of posts on ASP .NET Core 3.1 for 2020. In this series, we’ll cover 26 topics over a span of 26 weeks from January through June 2020, titled ASP .NET Core A-Z! To differentiate from the 2019 series, the 2020 series will mostly focus on a growing single codebase (NetLearner!) instead of new unrelated code snippets week.

Previous post:

NetLearner on GitHub:

In this Article:

K is for Key Vault for ASP .NET Core 3.1 Web Apps

In my 2018 blog series, we covered the use of User Secrets for your ASP .NET Core web application projects. This is useful for storing secret values locally during development. However, we need a cloud-based scalable solution when deploying web apps to Azure. This article will cover Azure Key Vault as a way to store and retrieve sensitive information in Azure and access them in your web application.

You will need an Azure subscription to create and use your own Key Vault and App Service.

Using Key Vault from Azure for your Web Apps
Using Key Vault from Azure for your Web Apps

Setting up Key Vault in Azure

Before you can use Key Vault in the cloud, you will have to set it up in Azure for your use. This can be done in various ways:

  • Azure Portal: log in to the Azure Portal in a web browser.
  • Azure CLI: use Azure CLI commands on your development machine.
  • Visual Studio: use the VS IDE on your development machine.

To use the Azure Portal: create a new resource, search for Key Vault, click Create and then follow the onscreen instructions. Enter/select values for the following for the key vault:

  • Subscription: select the desired Azure subscription
  • Resource Group: select a resource group or create a new one
  • Name: alphanumeric, dashes allowed, cannot start with number
  • Region: select the desired region
  • Pricing Tier: select the appropriate pricing tier (Standard, Premium)
  • Soft Delete: enable/disable
  • Retention Period: enter retention period (in days)
  • Purge protection: enable/disable
Key Vault creation screen on Azure Portal
Key Vault creation screen on Azure Portal

If you need help with the Azure Portal, check out the official docs at:

To use the Azure CLI: authenticate yourself, run the appropriate commands to create a key vault, add keys/secrets/certificates and then authorize an application to use your keys/secrets.

To create a new key vault, run “az keyvault create” followed by a name, resource group and location, e.g.

az keyvault create --name "MyKeyVault" --resource-group "MyRG" --location "East US"

To add a new secret, run “az keyvault secret set“, followed by the vault name, a secret name and the secret’s value, e.g.

az keyvault secret set --vault-name "MyKeyVault" --name "MySecretName" --value "MySecretValue"

If you need help with the Azure CLI, check out the official docs at:

To use Visual Studio, right-click your project in Solution Explorer, click Add | Connected Service, select “Secure Secrets with Azure Key Vault” and follow the onscreen instructions.

If you need help with Visual Studio, check out the official docs at:

Add a Connected Service in Visual Studio
Add a Connected Service in Visual Studio

Once created, the Key Vault and its secret names (and values) can be browsed in the Azure Portal, as seen in the screenshots below:

Key Vault details
Key Vault creation in Azure Portal
Key Vault creation in Azure Portal
Creating a secret for Azure Key Vault
Creating a secret for Azure Key Vault

NOTE: If you create a secret named “Category1–MySecret”, this syntax specifies a category “Category1” that contains a secret “MySecret.”

Retrieving Key Vault Secrets

Before you deploy your application to Azure, you can still access the Key Vault using Visual Studio during development. This is accomplished by using your Visual Studio sign-in identity. Even if you have multiple levels of configuration to retrieve a secret value, the app will use the config sources in the following order:

  • first, check the Key Vault.
  • if Key Vault not found, check secrets.json file
  • finally, check the appsettings.json file.

There are a few areas in your code you need to update, in order to use your Key Vault:

  1. Install the nuget packages AppAuthentication, KeyVault and AzureKeyVault NuGet libraries.
    • Microsoft.Azure.Services.AppAuthentication
    • Microsoft.Azure.KeyVault
    • Microsoft.Extensions.Configuration.AzureKeyVault
  2. Update Program.cs to configure your application to use Key Vault
  3. Inject an IConfiguration object into your controller (MVC) or page model (Razor Pages, shown below)
  4. Access specific secrets using the IConfiguration object, e.g. _configuration[“MySecret”]

Below is an example of Program.cs using the WebHostBuilder’s ConfigureAppConfiguration() method to configure Key Vault. The keyVaultEndpoint is the fully-qualified domain name of your Key Vault that you created in Azure.

...
using Microsoft.Azure.KeyVault;
using Microsoft.Azure.Services.AppAuthentication;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Configuration.AzureKeyVault;
...
public static IHostBuilder CreateHostBuilder(string[] args) =>
   Host.CreateDefaultBuilder(args)
      .ConfigureAppConfiguration((ctx, builder) =>
      {
         var keyVaultEndpoint = GetKeyVaultEndpoint();
         if (!string.IsNullOrEmpty(keyVaultEndpoint))
         {
            var azureServiceTokenProvider = new AzureServiceTokenProvider();
            var keyVaultClient = new KeyVaultClient(
               new KeyVaultClient.AuthenticationCallback(
                  azureServiceTokenProvider.KeyVaultTokenCallback));
               builder.AddAzureKeyVault(
                  keyVaultEndpoint, keyVaultClient, new DefaultKeyVaultSecretManager());
         }
      }
   ).ConfigureWebHostDefaults(webBuilder =>
   {
      webBuilder.UseStartup<Startup>();
   }); 

private static string GetKeyVaultEndpoint() => "https://<VAULT_NAME>.vault.azure.net/";

NOTE: Please note that usage of Web Host Builder in ASP .NET Core 2.x has been replaced by the Generic Host Builder in .NET Core 3.x.

Below is an example of of a Page Model for a Razor Page, e.g. SecretPage.cshtml.cs in the sample app

...
using Microsoft.Extensions.Configuration;
public class SecretPageModel : PageModel
{
   public IConfiguration _configuration { get; set; }
   public string Message1 { get; set; }
   public string Message2 { get; set; }
   public string Message3 { get; set; } 

   public SecretPageModel(IConfiguration configuration)
   {
      _configuration = configuration;
   }

   public void OnGet()
   {
      Message1 = "My 1st key val = " + _configuration["MyKeyVaultSecret"];
      Message2 = "My 2nd key val = " + _configuration["AnotherVaultSecret"];
      Message3 = "My 3nd key val ? " + _configuration["NonExistentSecret"];
   }
}

In the above code, the configuration object is injected into the Page Model’s SecretPageModel(). The values are retrieved from the collection in the OnGet() method and assigned to string properties. In the code below, the string properties are accessed from the model class in the corresponding Razor Page, SecretPage.cshtml.

@page
@model KeyVaultSample.Pages.SecretPageModel
...
<p>
 @Model.Message1
</p> 

<p>
 @Model.Message2
</p> 

<p>
 @Model.Message3
</p>

Finally, viewing the page allows you to navigate to the Secret Page to view the secret values. Note that I’ve only created 2 secret values before deploying this instance, so the 3rd value remains blank (but without generating any errors).

SecretPage showing secrets retrieved from Key Vault
SecretPage showing secrets retrieved from Key Vault

Managed Service Identity

There are multiple ways to deploy your ASP .NET Core web app to Azure, including Visual Studio, Azure CLI or a CI/CD pipeline integrated with your source control system. If you need help deploying to Azure App Service, check out the following article from this blog series:

You can set up your Managed Service Identity in various ways:

  • Azure Portal: log in to the Azure Portal and add your app
  • Azure CLI: use Azure CLI commands to set up MSI
  • Visual Studio: use the VS IDE while publishing

Once you’ve created your App Service (even before deploying your Web App to it), you can use the Azure Portal to add your app using Managed Service Identity. In the screenshots below, I’ve added my sample app in addition to my own user access.

  • In the Access Policies section of the Key Vault, you may add one or more access policies.
  • In the Identity section of the App Service, you may update the System-Assigned setting to “On” and make a note of the Object ID, which is defined as a “Unique identifier assigned to this resource, when it’s registered with Azure Active Directory“
Key Vault Access Policies
Key Vault Access Policies
Key Vault App Service Identity
Key Vault App Service Identity

To use the Azure CLI to authorize an application to access (or “get”) a key vault, run “az keyvault set-policy“, followed by the vault name, the App ID and specific permissions. This is equivalent to enabling the Managed Service Identity for your Web App in the Azure Portal.

az keyvault set-policy --name "MyKeyVault" --spn <APP_ID> --secret-permissions get

To use Visual Studio to use your key vault after deployment, take a look at the Publish screen when deploying via Visual Studio. You’ll notice that there is an option to Add Dependencies, including Azure Key Vault. After you’ve added and enabled Key Vault for your application, the option will change to say “Configure” and “Manage Key Vault”.

Add Dependencies during Publish from Visual Studio
Add Dependencies during Publish from Visual Studio
Select Azure Key Vault from list of dependencies
Select Azure Key Vault from list of dependencies

After adding via Visual Studio during the Publish process, your Publish Profile (profile – Web Deploy.pubxml) and Launch Settings profiles (launchSettings.json) should contain the fully qualified domain name for your Key Vault in Azure. You should not include these files in your source control system.

References

Deploying ASP .NET Core 3.1 to Azure App Service

By Shahed C on January 27, 2020
6 Replies

This is the fourth of a new series of posts on ASP .NET Core 3.1 for 2020. In this series, we’ll cover 26 topics over a span of 26 weeks from January through June 2020, titled ASP .NET Core A-Z! To differentiate from the 2019 series, the 2020 series will mostly focus on a growing single codebase (NetLearner!) instead of new unrelated code snippets week.

Previous post:

NetLearner on GitHub:

In this Article:

D is for Deploying to Azure App Service

In this article, we’ll explore several options for deploying an ASP .NET Core web app to Azure App Service in the cloud. From the infamous Right-Click-Publish to fully automated CI/CD, you’ll learn about the latest Deployment Center option in the Azure Portal for App Service for web apps.

NOTE: If you’re looking for information on deploying to Docker or Kubernetes, please check out the following docs instead:

Right-Click Publish (aka Friends Don’t Let Friends Right-Click Publish)

If you’ve made it this far, you may be thinking one of the following:
a. “Hey, this is how I deploy my web apps right now!”
or
b. “Hey wait a minute, I’ve heard that you should never do this!”

Well, there is a time and place for right-click publish. There have been many debates on this, so I won’t go into the details, but here are some resources for you to see what others are saying:

So, what’s a web developer to do? To quote from the aforementioned MSDN article, “Continuing with the theme of prototyping and experimenting, right click publish is the perfect way for existing Visual Studio customers to evaluate Azure App Service (PAAS). By following the right click publish flow you get the opportunity to provision new instances in Azure and publish your application to them without leaving Visual Studio:”

In other words, you can use this approach for a quick test or demo, as shown in the screenshots below for Visual Studio.

  1. Right-click your ASP .NET Core web app project in Solution Explorer and select Publish.
  2. Click the Start button on the screen that appears and follow the onscreen instructions.
  3. Ensure that you’re logged in to the correct Azure subscription account you want to publish to.
Right-click, Publish from Solution Explorer
Right-click, Publish from Solution Explorer
Pick a Publish Target
Pick a Publish Target

Web Apps in the Azure Portal

In the screenshot above, you may notice an option to “Import Profile” using the button on the lower left. This allows you to import a Web App profile file that was generated by exporting it from an existing Azure Web App. To grab this profile file, simply navigate to your existing Web App in the Azure Portal and click on “Get publish profile” in the top toolbar of your Web App, shown below:

Get Publish Profile
Get Publish Profile

If you want to create a new Web App in Azure starting with the Azure Portal, follow the instructions below:

  1. Log in to the Azure at https://portal.azure.com
  2. On the top left, click + Create a resource
  3. Select “Web App” or search for it if you don’t see it.
  4. Enter/select the necessary values:
    • Subscription (select a subscription)
    • Resource Group (create or use existing to group resources logically)
    • Web App name (enter a unique name)
    • Publish (Code or Docker Image)
    • Runtime stack (.NET Core)
    • App Service Plan (create or use existing to set location and pricing tier)
    • OS (Windows or Linux)
    • Region (e.g. East US)
  5. Click Next through the screens and then click the Create button to complete the creation of your new Web App.
Create New Web App
Create New Web App

Now you can deploy to this Web App using any method you choose.

Runtime Options

If you like to stay ahead of ASP .NET Core releases, you may be using a pre-release version of the runtime. As of this writing, the latest stable version of ASP .NET Core is version 3.1, which is already available on Azure. If you’re looking for future preview releases, Azure App Service also has an option to install an Extension for preview runtimes.

To find the proper runtime:

  1. Navigate to your Web App in the Azure Portal.
  2. Click on Extensions under Development Tools.
  3. Click + Add to add a new extension.
  4. Choose an extension to configure required settings.
  5. Accept the legal terms and complete the installation.
Add Extension
Add Extension

Your options may include both 32-bit (x86) and 64-bit (x64) versions of the ASP .NET Core runtime and any preview versions of future releases. When planning ahead for multiple environments, you also have the option to deploy to Deployments Slots. This feature is available in Standard, Premium or Isolated App Service Plan tiers and will covered in a future blog post in this series.

If you’re interested in Deployment Slots right now, check out the official docs at:

Deployment Center

In the list of features for your Web App, you will find an option to open up the new Deployment Center. Note that this has replaced the old Deployment Options. Let’s go over each of these options:

  1. Azure Repos
  2. Github
  3. Bitbucket
  4. Local Git
  5. OneDrive
  6. Dropbox
  7. External
  8. FTP
Deployment Options in Deployment Center
Deployment Options in Deployment Center
More Deployment Options
More Deployment Options

If you choose Azure Repos, you can set up your web app’s CI (Continuous Integration) system with an Azure Repo, which is part of Microsoft’s Azure DevOps services (formerly known as VSTS, aka Visual Studio Team Services). You will have options for using App Service as a Kudu build server or Azure Pipelines as your CI build system.

Azure Repos choices: Kudu or Pipelines?
Azure Repos choices: Kudu or Pipelines?

If you choose Github or BitBucket or even a local Git account, you’ll have the ability to authorize that account to publish a specific repo, every time a developer pushes their code.

Authorize Github/Bitbucket
Authorize Github/Bitbucket

If you choose OneDrive or DropBox, you’ll have ability to authorize your App Service to pick up files deployed to a shared folder in either location.

Authorize OneDrive/DropBox
Authorize OneDrive/DropBox

You may also select an External repo or FTP source. To learn more about Azure Repos and Azure Pipelines, check out the official docs:

GitHub Repos (includes FREE option!)

If you’ve been using GitHub for public open-source projects or private projects on paid accounts, now is a great to time to create private repositories for free! In 2019, GitHub started offering free unlimited private repos, limited to 3 collaborators. This new free option comes with issue/bug tracking and project management as well.

For more information on GitHub pricing, check out their official pricing page:

GitHub pricing: Free vs Pro, Team and Enterprise
GitHub pricing: Free vs Pro, Team and Enterprise

Now you can easily set up your starter projects in a private GitHub repository and take advantage of the aforementioned CI/CD setup without having to choose between paying a GitHub fee or making all your repos public.

CLI Commands

If you wish to publish to Azure App service using CLI (Command Line Interface) Commands, you may use the following commands, where you can choose a name for your Web App, Resource Group, App Sevice Plan, etc. Single-letter flags are usually preceded by a single hyphen, while flags spelled out with completed words are usually preceded by two hyphens.

First, install the Azure CLI in case you don’t have it already:

Authenticate yourself:

> az login

Create a new resource group:

> az group create -l <LOCATION> -n <RSG>
> az group create --location <LOCATION> --name <RSG>

Create a new App Service Plan, where <SKUCODE> sku may be F1 or FREE, etc

> az appservice plan create -g <RSG> -n <ASP> --sku <SKUCODE> 
> az appservice plan create --resource-group <RSG> --name <ASP> --sku <SKUCODE>

From the documentation, the SKU Codes include: F1(Free), D1(Shared), B1(Basic Small), B2(Basic Medium), B3(Basic Large), S1(Standard Small), P1V2(Premium V2 Small), PC2 (Premium Container Small), PC3 (Premium Container Medium), PC4 (Premium Container Large), I1 (Isolated Small), I2 (Isolated Medium), I3 (Isolated Large).

Create a new Web App within a Resource Group, attached to an App Service Plan:

> az webapp create -g <RSG> -p <ASP> -n <APP> 
> az webapp create --resource-group <RSG> --plan <ASP> --name <APP>

The above command should create a web app available at the following URL:

  • http://<APP>.azurewebsites.net

To push your commits to a Git Repo and configure for App Service Deployment, use the following CLI commands:

Create a new Git repo or reinitialize an existing one:

> git init

Add existing files to the index:

> git add .

Commit your changes with a commit message:

> git commit -m "<COMMIT MESSAGE>“

Set your FTP credentials and Git deployment credentials for your Web App:

> az webapp deployment user set --user-name <USER>

Configure an endpoint and add it as a git remote.

> az webapp deployment source config-local-git -g <RSG> -n <APP> --out tsv  
> az webapp deployment source config-local-git --resource-group <RSG> --name <APP> --out tsv
> git remote add azure <GIT URL>

The value for GIT URL is the value of the Git remote, e.g.

  • https://<USER>@<APP>.scm.azurewebsites.net/<APP>.git

Finally, push to the Azure remote to deploy your Web App:

> git push azure master

For more information on CLI Commands for Git and Azure App Service, check out the official docs:

Azure DevOps and YAML

Wait, what about Azure DevOps and YAML and Pipelines?

Since this is an A-Z series, you will have to wait for “Y is for YAML” to get more detailed information on constructing your build pipeline using YAML in Azure DevOps. If you can’t wait that long, feel free to check out the following .yml sample I uploaded for use with an ASP .NET Core 3.1:

If you’re reading this after June 2020, simply jump right to the “Y is for YAML” post in the 2020 A-Z series.

BONUS: for Azure SQL Database Deployment, watch the following video on MSDN Channel 9:

References