Notes on Adding .NET Core 2.2 Identity to Existing Project

Even though all my projects are in .NET Core now, I rarely get the opportunity to use Identity because of my work with our backend Legacy system.  Recently, though, I built a very lightweight SEO Management system for one of our sites (that allows a 3rd party to tweak our page titles, meta tags, etc) and wanted to give them user access and roles.

The entire project can be found on GitHub, but below is just a running list of sites I used to get this done, noting all the troubleshooting and stupid little mistakes I did along the way.

Adding Identity to an Already Existing Project

This part was relatively easy and the Microsoft documents provided an easy enough guide.  I believe I had some issues:

CS1902 C# Invalid option for /debug; must be full or pdbonly – with the Data Migrations because I didn’t have EntityFramework installed.   Basically, all errors in this phase were not as presented – they were mostly because I was lacking packages to migrate.

To ensure I had all the right packages installed, i used: Microsoft.AspNetCore.App -Version 2.2.6

Also, in this area, I decided not to put the connection string in appsettings.json, opting …

Making Session Variables Work in .NET Core

The Problem

As noted, I work with Legacy and often have to bring in variables from the API that must be sustained across session.. (and I’m sure there might be a better way, comment and advise!).  Where I am at now, is I query the API and bring in the variables, but how do I keep from calling these over and over?  The old solution was session variables and so, that’s where I am at.

When I started to do this on Core, the most helpful article was this (and it’s in my comments):

https://adamstorr.azurewebsites.net/blog/are-you-registering-ihttpcontextaccessor-correctly

He leads you through the basic setup of a HttpContext helper class (that I still use today) and how to configure the startup..  Today, though, I came across a problem: I was able to Set session variables, but the Get was pulling null.

The Reason

Order.  Yes, you’ll see 1000 stackflow responses about order in Configure (and I was careful to do this in that method), but now in ConfigureServices (contrary to the example, as I am now using Core 2.2?), order again comes into play:

public void ConfigureServices(IServiceCollection services)
{
    //this MUST be before add mvc or session returns null
    services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
    services.AddMvc();

First Heroku App: Small API in PHP to Talk to .Net Core

I’ve recently been curious about switching to a time API for my time stamps and removing any dependency the app might have on the server for a timestamp.  Upon Googling I found some paid services, some free and of the free ones, I noticed one was hosted on Heroku.  I’ve heard of Heroku, but never had a reason to attempt to use it.  This was the perfect chance.

How I Created a Small “GetTime” API

First, I created a free account on Heroku, nothing special.  After verifying my email, I logged in to my Heroku Dashboard and up on the right hand corner, selected Create New App.  I named it my company-api and out popped an app.

I decided on just plain, legacy PHP and a simple DateTime string passed thru JSON encode, just to get started.  No authentication, no timezone,  just a simple spit out if a request to the site came, like this:

<?php
    header('Content-type:application/json;charset=utf-8');

    $DateTime = new DateTime();
    $currentTime = $DateTime->format("Y-m-d H:i:s");
    echo json_encode($currentTime);
?>

I created a Git repo for this brand new file and pushed it out.  Then, I went back to Heroku, Dashboard, My App and Deploy.  I selected Github as my deploy “resource” …

Share Azure Blobs with Search and Tree View

The idea behind this was to create a nice, easy UI that users can download media files they request often.  We moved it to Azure to prevent killing our on-prem bandwidth, but then I had to deal with the flat file structure, etc.  The end result was simply: a fast search of all the blobs (with link) and underneath that, a tree structure of the blobs that they can browse through.

The Set Up

First, I created a Storage container through Azure Portal, then I used Azure Storage Explorer to create a Blob Container under that storage account.  I also set read-only permissions to my blobs by right clicking the container in Azure Storage Explorer, then: Set Container Public Access Level > Public Read Access for Blobs Only.

To make this code work, I needed to setup an environment variable for my connection string.  I used the prefix CUSTOMCONNSTR_ on my variable name as it comes in handy when deploying to Azure Web Apps.  To get the connection string:  Azure Portal > Storage Account you created > Access Keys.

setx CUSTOMCONNSTR_storageConnectionString "<yourconnectionstring>"

Finally, I got a folder I wanted to share and dragged and dropped it into my …

Print PDF’s on Azure Using an API and RazorLight (Update 1)

The API mentioned in my first tutorial got taken down and so I had to do some updates.  First, choose another 3rd party API.  I currently am trying out  HTML 2 PDF Rocket and modified my code a bit:

[HttpGet]
public async Task<FileStreamResult> PrintAsync(int id)
{
    InvoiceVM invoiceVM = new InvoiceVM();
    invoiceVM = invoiceRepository.Get(id);

    var engine = new RazorLightEngineBuilder()
      .UseFilesystemProject(_hostingEnvironment.WebRootPath + "\\pdf\\")
      .UseMemoryCachingProvider()
      .Build();

    var view = await engine.CompileRenderAsync("PDF.cshtml", invoiceVM);
    string apiKey = "xxxxxxxxxxxxxxxxxxxx";

    using (var client = new WebClient())
    {
        // Build the conversion options
        NameValueCollection options = new NameValueCollection();
        options.Add("apikey", apiKey);
        options.Add("value", view);
        options.Add("MarginLeft", "10");
        options.Add("MarginRight", "10");
        options.Add("MarginTop", "10");
        options.Add("MarginBottom", "10");
        options.Add("PageSize", "Letter");

        MemoryStream ms = new MemoryStream(client.UploadValues("http://api.html2pdfrocket.com/pdf", options));

        return new FileStreamResult(ms, "application/pdf");
    }
}

This is based directly off the HTML 2 Rocket documentation.  For the rest of the code see the first tutorial.

 …

Using Libman Providers to Coral Front End Libraries

The first package management system I learned to use was Bower.  It was great for the short love affair we had together, but it stopped being supported and I was weary of learning to use one of its replacements.  Fortunately, I haven’t had to with Libman.  Libman’s (Library Manager) simple JSON approach to bringing front end dependencies has been the easiest for me quickly implement and it has been a great addition to Visual Studio.  I implemented it possibly too quickly, however, and overlooked one powerful configuration setting:  provider.