Azure App Service with On-premises Connection

Imagine you get a new project with the ability to use whatever cloud services you want. You jump at the change and dream up an amazing architecture using Azure. Next, you present your plan to the rest of your team and discover a new requirement of having to use an existing on-premises database.

Does this mean your grand plans are shot? Thankfully not, as Azure has multiple solutions that allow you to connect to your existing on-premises resources to enable hybrid cloud strategies.

In this post, we are going to use one of the options, Hybrid Connections, to connect from a web site hosted in an App Service to an on-premises database.

Sample Application

The base sample application we will be using for this post is a new Razor Pages App targeting .NET Core 3. We will walk through actually connecting to the database later in this post. To get started you need the new app created and running in an Azure App Service.

I have multiple walkthroughs of creating a new application and publishing them to Azure so I’m not going to rehash that here. If you need help getting your app created and published to Azure you can check out my Deploying an ASP.NET Core Application to Microsoft Azure post and instead of using the Razor template use the Web App template like the following.

dotnet new webapp

Also, note that Hybrid Connections aren’t available on the free or shared hosting plans so when you are setting up your publish profile avoid those options.

Add a Hybrid Connection to an App Service

From the Azure Portal open the App Serice you created above and under the Settings section of the menu click Networking.

In the networking details, we want to click Configure your hybrid connection endpoints.

I’m going to point out again that Hybrid Connections aren’t available at free and shared scales levels. If your App Service is on a free or shared scale use the Scale up menu option to switch to a scale level that will support Hybrid Connections.

From the Hybrid connections detail page click Download connection manager. When done this will need to be installed on the machine that is running the on-premises database you want to connect to.

Next, click Refresh and then click Add hybrid connection.

Now on the Add hybrid connection page click Create new hybrid connection.

In order to create a new hybrid connection, Azure will require some information. The key parts here are the Endpoint Host which is the name of the machine that is hosting the database you wish to communicate with and the Endpoint Port which will need to be the port that your database is configured to communicate over.

Hybrid Connection Manager on the host machine

Now that the Azure side is configured we need to use the Hybrid Connection Manager application that we installed on the target machine above to allow talk to our App Service.

After opening the Hybrid Connection Manager on the target machine click Add a new Hybrid Connection.

Now Select the Subscription the App Service is a part of. After the list of available connections, loads select the one created above and finally click Save.

After making the above changes my hybrid connection continued to show offline in Azure. After some searching, I found a blog post that suggested restating the Azure Hybrid Connection Manager Service which cleared the problem up for me.

Sample Application Changes to Connect to On-Premises Database

This is a very raw test, but it gets the point across. First, add a reference to the System.Data.SqlClient NuGet package. Next in the Index.cshtml.cs delete the OnGet function and replace it with the following.

public async Task OnGetAsync()
{
    Tables.Clear();
    var connectionString = "data source=Server;initial catalog=master; User Id=User;Password=Password"";
    await using var connection = new SqlConnection(connectionString);
    await connection.OpenAsync();
    await using var command = 
                    new SqlCommand("SELECT name FROM sys.tables", connection);
    await using var reader = command.ExecuteReader();

    while (await reader.ReadAsync())
    {
        Tables.Add(reader["name"].ToString());
    }
}

The above connects to the master database on the specified server and pulls a list of table. Note that you will need to modify the connection string to something valid for your system. It is also important to know that you can’t use integrated security with this setup so you will need to specify a user and password that exists on your SQL Server. Add the following property in the same file.

public List<string> Tables { get; set; } = new List<string>();

Add the following to the bottom of the Index.cshtml which will output the table list we pulled above to the page.

@foreach (var table in Model.Tables)
{
    @table <br/>
}

After the changes are done republish the application to your Azure App Service. After the publish is done your site should show with a list of tables that exist in the master database of your SQL Server.

Wrapping Up

Hybrid connections is a great way to take a workload to the cloud without having to actually move all your data. It is also one of those features of Azure that I had no idea that existed before a week ago.

If you need a lot of hybrid connections look closely at the pricing as the number you can use is tied to what App Service scale you are using. The number of available starts at 5 and can go up to 200 with the more expensive App Service scales.

Publish a .NET Core Worker Service to Azure

In last week’s post, .NET Core Worker Service, we created a .NET Core Worker Service and then showed how to host it as a Windows Service. This week we will be taking the application created in last week’s post and publishing it to Azure. If you haven’t read last week’s post I recommend you at least get through the application creation bits. Feel free to skip the part about making the application run as a Windows Service since we will be pushing to Azure for this post.

Publish to Azure

This post is going to assume you already have an active Azure account. If not you can sign up for a free Azure account. This post is also going to be using Visual Studio 2019 Preview for the publication process.

In Visual Studio right-click on the project and click Publish.

Since this project already has a folder publish setup from last week’s post my screenshot might look different from yours. Click the New link.

This will launch the Publish profile dialog. We will be publishing to Azure WebJobs using the Create New option. After verifying the settings are correct click Create Profile.

The next screen gets the details of the App Service that will be created. I did a new resource group instead of using the one that was defaulted in and a new hosting plan so that I could utilize the free tier, but both of these changes are optional. When you have everything set click the Create button.

Once create is clicked it takes a couple of minutes to deploy the application. This first deploy is going to be a throwaway for us. There are a few settings we need to tweak to get the application running the way we want. After the initial deployment is complete we end up back on the profile details screen. Click the Edit link.

The Publish Profile Settings dialog will show. Since this was written while .NET Core 3 is still in preview I’m using the Self-contained option for Deployment Mode. If you are doing this after the final release then you can skip this step. The second thing I am changing is the WebJob Type and I’m setting it to Continuous. This is because our Service is controlling its own work schedule and not being triggered by something else. Click Save to commit the changes and return to the publish dialog.

Now push the Publish button to push the application to Azure.

Use Azure Portal to Verify Application is Working

Now that our application is running in Azure how do we verify that it is actually executing as we expect? Since the only thing the sample application does it output some logs we are going to have to find a way to show the output of the logging. To start head over to the Azure Portal. Since we just published the application the resource we are interested in should show in your Recent resources section of the Azure Portal homepage. As you can see in the screenshot the one we are interested in is the first option and matches the name we saw above in Visual Studio. Click on the resource.

From the menu section scroll down to the Monitoring section and click App Service logs. Now turn On the option for Application Logging (Filesystem) and for the Level option select Information since that is the log level our sample application is outputting. Then click Save.

Back in the same Monitoring group of the menu select Log stream.

Wrapping Up

Running a worker in Azure ended up being pretty simple. Not that I’m surprised Microsoft tends to make all their products work well with Azure. I’m sure you will find a way to make a more useful worker than we had in this example.

Azure Function App Log Streaming

One of the things I have noticed while exploring Azure Function Apps is it is important to find ways to track what is going on during execution. While exploring the Azure Portal for one of my functions apps I noticed an option for steaming logs. This post is going to show how to get to the streaming logs for a Function App.

Log Streaming Location

From the Azure Portal open your Function App and select Platform features and then click the Log streaming link.

Log Streaming View

The following screenshot is from my sample App and has two different function executions listed.

Wrapping Up

For this small sample application, this feature isn’t critical, but on a larger application, it would become much more important. Log streaming is a quick way to get an idea of what is going on, but would only be one part of knowing what is going on.

Create an Azure Function App from Visual Studio

When I started looking at Azure Function Apps in the post, Azure Functions Introduction, I used the Azure Portal to create the sample function App used in the post. On the follow-up post, Open an Azure Portal Created Function in Visual Studio, I showed how to get a portal created function to open in Visual Studio. The code download from the Azure Portal was in the csx format instead of the cs format that Visual Studio normally deals with so a lot of Visual Studio doesn’t work.

This post is going to walk through creating a new Azure Function App from within Visual Studio. My hope is that starting from Visual Studio will result in code that is more Visual Studio friendly. This post will be using Visual Studio 2019.

App Creation

Open Visual Studio and click  Create a new project on the start dialog.

On the next screen search from Azure Functions. Click on the Azure Functions item and click the Next button.

Enter a Project name, and change any other settings if needed, then click Create.

The next dialog will ask for the type of trigger to use. To match the function we created a few weeks ago on the Azure Portal we are going to use an Http trigger and click Create.

Clicking the last Create button will kick off the project creation process. When done you will have a project with a single function that will match the following inside of the file Function1.cs.

public static class Function1
{
    [FunctionName("Function1")]
    public static async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
        ILogger log)
    {
        log.LogInformation("C# HTTP trigger function processed a request.");

        string name = req.Query["name"];

        string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
        dynamic data = JsonConvert.DeserializeObject(requestBody);
        name = name ?? data?.name;

        return name != null
            ? (ActionResult)new OkObjectResult($"Hello, {name}")
            : new BadRequestObjectResult("Please pass a name on the query string or in the request body");
    }
}

The following is the Portal created function from a few weeks ago.

public static async Task<IActionResult> Run(HttpRequest req, ILogger log)
{
    log.LogInformation("C# HTTP trigger function processed a request.");

    string name = req.Query["name"];

    string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
    dynamic data = JsonConvert.DeserializeObject(requestBody);
    name = name ?? data?.name;

    return name != null
        ? (ActionResult)new OkObjectResult($"Hello, {name}")
        : new BadRequestObjectResult("Please pass a name on the query string or in the request body");
}

You will notice that the body of the two is the same. The Visual Studio version is using attributes to let Azure know the name, the trigger type, and other information that will be needed once the function is published to Azure.

Local Testing

One really neat thing about using Visual Studio for your function development is you can debug them locally. If you hit the play button (or F5) Visual Studio will launch your function locally. You will see something like the following.

Highlighted is the section listing all the Http Functions in the applications along with URLs that can be used to test them. For this example, the following URL could be used to get the response “Hello, Eric”.

http://localhost:7071/api/Function1?name=Eric

As far as I have seen so far all the normal debugging features of Visual Studio seem to work when running a function locally.

App Publication

Now that we have created and tested our Function App locally it is time to publish it to Azure. Right-click on the project file in Solution Explorer and click Publish.

On the Publish dialog, we are going to Create New and Run from package file since it is recommended (see the docs for why it is recommended). Finally, click the Publish button.

The next dialog is the configuration for the App Service that will be created in Azure. You can take the defaults and hit Create, but I always take the extra time to create a new resource group so that my samples are easy to remove when I am done with them.

Clicking the create button will start the deployment to Azure which will take a few minutes. After the deployment, you can use the Azure Portal to test your Function App. More information on running a function from the Azure Portal can be found in the Azure Functions Introduction post.

Wrapping Up

While creating a function via the Azure Portal is the fastest way to get started, I would recommend you start locally. The slightly longer getting started time it worth it for the better tooling and flexibility it provides.

Open an Azure Portal Created Function in Visual Studio

In last week’s post, Azure Functions Introduction, we created a new Azure Function App with a single function triggered via HTTP. The Portal is great for the initial creation of a function, but what happens when your needs change? For instance, you might want to store your functions in a repo with the rest of the code for your application. In this post, we are going to walk through taking our portal created function and getting it downloaded where it can be edited in Visual Studio.

Download App Content

From the Azure Portal select App Services.

Next, select the Function App you want to get the code for.

The detail of the Function App will load and at the top of the screen click on the Download app content option.

On the popup that shows select Content and Visual Studio Project and then click the Download button.

Once clicking download you will get a zip file containing everything in your Function App. Extract the files and double click the project file to open it in Visual Studio.

Changing a Function

The project will have a folder per function that exist in your applications. In our example, you would see a HttpTrigger1 directory and inside that directory, the code for the actual function is in the run.csx file.  Looking at the code you will see that it is the same that you would have seen in the portal. Here is the code.

#r "Newtonsoft.Json"

using System.Net;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;

public static async Task<IActionResult> Run(HttpRequest req, ILogger log)
{
    log.LogInformation("C# HTTP trigger function processed a request.");

    string name = req.Query["name"];

    string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
    dynamic data = JsonConvert.DeserializeObject(requestBody);
    name = name ?? data?.name;

    return name != null
        ? (ActionResult)new OkObjectResult($"Hello, {name}")
        : new BadRequestObjectResult("Please pass a name on the query string or in the request body");
}

At this point, you could change anything you wanted about the application. I’m going to change the return value.

Before:
(ActionResult)new OkObjectResult($"Hello, {name}")

After:
(ActionResult)new OkObjectResult($"Yo, {name}")

Pushing Changes back to Azure

Now that we have a change to our function how do we get that change back to Azure? Head back to the overview page for your Azure Function App and click the Get publish profile link.

In Visual Studio right-click on the project and select Publish.

In the publish dialog click the Import Profile button and select the profile you download from Azure.

Once the profile is imported you can then click the Publish button to push any changes to your Azure Function App.

At this point, if you execute your function you should see the changes you made in Visual Studio.

Wrapping Up

While the above works it isn’t actually very friendly in Visual Studio since the function is a csx file instead of a cs file that normal C# uses. For next week look for an example of starting a function app from Visual Studio to see if it results in a project that will be easier to maintain.

Deploy ASP.NET Core 3 Previews to Azure App Using Extensions

A few weeks ago when the post Deploy ASP.NET Core 3 Previews to Azure App Service I got an email from Jerrie Pelser who pointed out that there are extensions available for App Service that allow usage of the public previews of ASP.NET Core 3 without having to do a self-contained deployment.

In addition to Jerrie’s suggestion pajaybasu pointed out in this Reddit post that using Docker is another option. Pajaybasu also pointed out a line in the original post where I that self-contained deployments were the only option which of course was incorrect.

The first half of this post is going to be the same as the original post which covers the creation and the initial publication to Azure App Service. The last half will cover using an extension to enable the preview version of ASP.NET Core.

Sample Application

I used the following .NET CLI command to create a new ASP.NET Core application using React for its front end.

dotnet new react

After the creation process is complete open the project in Visual Studio. I highly recommend using the Visual Studio 2019 preview release when working with any .NET Core 3 applications.

Publish to App Service

In Visual Studio’s Solution Explorer right click on the project file and select Publish.

Select App Service for the publish target. Here we are creating a new app service. Next, click Publish.

The next dialog if the information about the new App Service that will be created. I took the defaults for the most part. I did create a new resource group for this application to make the resources easier to clean up in the future. I also changed the hosting plan to the free tier. Click Create to continue.

The Error and the Warning

As part of the publishing process, a browser will be opened to the address of the application. When this happens you will see an error about ANCM In-Process Handler Load Failure (if you are using IIS In-Process Hosting).

If you look back at Visual Studio you will see the following warning that your application requires the .NET Core runtime 3.0 and App Service only supports up to 2.2. Since we are going to fix this in App Service I recommend selecting Don’t perform check in the future (only this profile).

Another Fix

For this version of the fix, go to your App Service in the Azure Portal. In the menu under the Development Tools select the Extensions option.

On the next page click the Add button at the top. Click on the Choose Extension and select the ASP.NET Core 3.0 (x86) Runtime option.

Next, click Legal Terms, read the terms and if you are OK with the terms then click the OK button. You will then have to click OK on the add extension blade which will start the extension installation.

If you were to load your site at this point you would still get the 500 error. Under Settings click the Configuration and click on General settings turn Web sockets On and click Save.

At this point, your site should be working. You can also go back and turn web sockets back off and the site will continue working. I have no idea what toggling web sockets does to make everything start working, but thanks to this comment on a GitHub issue for the key to getting this working.

Wrapping Up

Hopefully, between this post and the previous one using a self-contained deployment, you won’t have any issues trying out the .NET Core 3 with App Service.

Azure Functions Introduction

Serverless seems to be all the rage these days. Each of the major cloud providers has a serverless offering with Azure Functions, AWS Lambda, and Google Cloud Functions. One of the big selling points of serverless function is the automated scaling based on your workload and the low cost.

For example with Azure using consumption billing, you get 1 million executions for free with each additional million executions costing only $0.20. It does get more complex as there is a charge based on execution time mixed with resource consumption, but you can check out the pricing page for the details.

This post is going to cover creating and calling a very simple function. Note that you will need an Azure account, if needed you can sign up for a free account.

Function App Creation

There are a lot of options to create a new function using everything from Visual Studio to the Azure CLI. For this post, we will be using the Azure Portal to create our function. Head to the portal and using the search box at the top search for function and in the results select Function App.

The above will take you to a list of your functions apps. Click either the Add button at the top of the page or the Create Function App button to create a new Function App.

The next step has a lot of options, but for this first, go we are going enter an App name and take the defaults for the rest of the options and click Create.

Clicking create will queue the deployment of a new function app and return you to the list of function apps on your account. After a few minutes, your new app should show in the list, this took almost 3 minutes for me. Once your app shows in the list select it.

Add a Function

Now that we have a Functions App it is time to add a Function. On the menu click the next to Functions.

The next screen will ask you to select a development environment. I will be using the In-portal option. After making the selection click Continue.

The next page will ask about how the function should be triggered. We will be using the Webhook + API option. There are a lot of options for triggers I recommend selecting the More templates option and exploring at some point. When finished click the Create button.

After the creation is finished you will see the code for your new function, which is defaulted to take a request with a name and respond with hello using the name supplied.

From the above page, you can make changes to your function and save them. To try the function out hit the Run button. Hitting the run button will show you the Test area where you can change and run the request to your function as you want and use the Run button to send the request.

Wrapping Up

While we have only scraped the smallest part of the surface of Azure Function Apps I can see why people are excited about the value they can provide. It was surprisingly simple to get started.

Stay tuned if you are interested in functions as I  play to do more exploration on this topic.

Azure Application Insights: Analytics

I found one more feature of Azure Application Insights I wanted to point out before changing subjects. If you are just joining it might be worth checking out the previous entries in this series.

Add Application Insights to an Existing ASP.NET Core Application
Azure Application Insights Overview

Analytics

On the overview of your Application Insights resource click on the Analytics button.

This will take you to a page that will let you query your Application Insight data. The following is the page you will see with one of the example queries and the results it provides.

The official docs for Analytics provide a lot of good resources and I recommend checking them out. We are going to do some exploration in this post, but this post won’t be enough to fully explorer all you can accomplish with Analytics.

If you want to explore Analytics and you don’t have a site up yet or your site doesn’t have much data, like my sample application, check out the Analytics Playground provided by Microsoft.

Schema

Analytics provides a very powerful way to query for information about your application. The first thing I recommend you doing is exploring the schema of the data available. The left side of the page provides the details of the schema that is available. As you can see in the screenshot below you can query details from traces, page views, request, performance counts just to call out a few. Each type has its own set of fields available.

Query Entry

The query entry area is in the top center of the page. You can read up on the details of the query language here. Thankfully the query editor provides IntelliSense as you can see in the screenshot below.

While the syntax isn’t anything like SQL the data is organized in a way that having SQL experience helped me think about how to explored and relate the data.

Results

Clicking the Run button will execute your query and you will the results in the bottom of the page. As you can see the results default to a time chart based on the render statement in the query above.

The chart type can be changed in the results area. There is also an option to view results in a table view (this is the default view if you don’t have a render statement in your query).

Wrapping Up

It is amazing how many features Application Insights provides. I glad I happened to notice Analytics. If you are using Application Insights take the time and really explore all the features that it provides. You never know when you will find a feature that could up being a critical insight into your application.

Azure Application Insights Overview

In the Add Application Insights to an Existing ASP.NET Core Application post from last week, we got Application Insights up and running. This week my plan was to show off some of the features of Application Insights. It turns out this is hard to do in a meaningful way when your application isn’t getting any usage. While I have next to no data for most of the screenshots I still want to point out some of the areas of Application Insights that seem like they would be very useful.

Sample Application

For the most part, the post linked above is a good starting point with the exception of instead of using a React application I switched out for a Razor Pages application. The following is the command to create a Razor Page application with auth using the .NET CLI.

dotnet new webapp --auth Individual

The reason for this change was to get more items in App Insights since Razor Pages makes a request to the server per page.

Application Dashboard

The first item I recommend you check out is the Application Dashboard. On the Azure Portal select your App Insights resource and at the top click Application Dashboard.

This link will drop you on a page that will let you see how your application is doing at a glance. This includes everything from Unique sessions and Failed requests to Average I/O rate and Average available memory.

Live Metrics Stream

From your application dashboard or the App Insights menu you if you select Live Metrics Stream you will see real-time information about Incoming Requests, Outgoing Request, Overall Health, and a list of servers your application is running on and some stats about your usage on those servers.

Investigate

As a developer, a lot of the items in the Investigate menu jump out to me as being really helpful.

For example, Failures will give you a graph of failures over your selected timeframe with a list of the failed operations and a summary of the top 3 failed response codes, exception types, and dependency failures. The following screenshot is what it looks like, but my sample application doesn’t have any failures so it may not be super helpful.

The other option I want to point out is Performance which will give you a great summary of how your application is performing with break down by operation. This operation level view is a great place to spot areas in your application that may need some perf work.

Wrapping Up

This post covered a small fraction of the value provided by Application Insights. I encourage you to give the service a try especially if you are running a .NET application and most of the value can be provided without having to make any code changes.

Add Application Insights to an Existing ASP.NET Core Application

I have been using Azure’s App Service to host the web applications I am playing around with for a few years now. The service makes it simple to get an application hosted. Today I decided to try out Application Insights which is an application performance management (APM) service provided by Azure which integrates very well with App Service. In fact, you can enable Application Insights for your App Service Application without the need to make any code changes.

This post is going to cover using an existing App Service application and enabling Application Insights. This post is assuming that you already have an Azure account. If you don’t you can sign up for a free Azure account.

Sample Application and App Service Creation

In case you don’t have an existing application in Azure App Service here is a quick walkthrough of the application I used for this post. If you have an existing application you can skip to the next section.

From the .NET CLI I used the following command to create a global.json targeting .NET Core 2.2 in the directory the application is being created in. You don’t have to do this step, but I needed it because I have .NET Core 3 preview installed and I wanted this post to target the current production release of .NET Core.

dotnet new globaljson --sdk-version 2.2.105

Next, run the following command to create a new ASP.NET Core application using the React template. Any of the templates are fine so feel free to use a different one as long as it will give you a web application.

dotnet new react

Now open the new project in Visual Studio and right-click on the project file and click Publish.

Select App Service and then click Publish.

The next dialog is all about the setup of your App Service. I took the defaults for the most part, with the exception of the Resource Group which I made sure to create one just for this application to allow for easy clean up later. When you have all your options selected click Create. Note that there is an option to setup Application Insights from this screen, but we are going to handle this on the Azure side after the fact for this post.

After the deployment is done your application should open up in a browser.

Add Application Insights from the Azure Portal

Now that we have an application running in an Azure App Service we are ready to add in Application Insights. First head to the Azure Portal and select App Services from the menu.

From your list of App Services select the one you want to add Application Insights to. From the menu select Application Insights. In the details click the Turn on site extension button to update the Application Insights extension if needed.

On the next screen select the Location where you would like the Application Insights deployed. You can tweak what will be instrumented based on the language your application is built in, I just kept the defaults. When all your selections are done click Apply.

When you click apply, you will get a warning that your site will have to be restarted. For a test application, this isn’t a big deal, but if you are on a production application you might want to do this during a slow period. Click Yes to continue.

After the process is complete click the View Application Insights data link to view your Application Insights Overview.

The overview will give you a fast overview of how your application is doing with graphs of Failed request, Server response time, Server requests, and Availability.

Wrapping Up

Hopefully, this will help you get going with Application Insights. This post didn’t cover many of the features that Application Insights provides, but should get you set up so you can explore all the features the service provides.