How to Build a Blog App Using Blazor WASM and Strapi

This article has been updated to v4 by Mark Munyaka.

Learn how to create a simple but blazing-fast blog app using Blazor WebAssembly, Tailwind CSS, and Strapi. You will use Strapi, the leading open-source headless CMS, to store your posts and Blazor to build your front-end.

Prerequisites

Before you can jump into this content, you need to have a basic understanding of the following:

1. Strapi - get started here.
2. Node.js
3. Blazor
4. C#
5. Shell (Bash)

The following software should be installed:

• .NET SDK. Version 6 at the time of writing
• Node v14.x.x or v16.x.x. Download Node from the Download | Node.js page. I used Node v16.14.2.
• npm or yarn. npm ships with your Node installation. If you prefer yarn, install it as an npm package. Check Installation | Yarn.

For a full rundown of all the requirements needed to run a Strapi app, check out the Hardware and Software requirements.

Introduction

What is Blazor?

Blazor is a web framework from Microsoft which allows you to create a web application using C# and HTML. If you are a developer using C# and want to build a blazing-fast web application, you should check out Blazor.

According to Blazor's docs:

Blazor is a free, open-source web framework that enables developers to create web apps using C# and HTML.

Blazor lets you build interactive web UIs using C# instead of JavaScript. Blazor apps are composed of reusable web UI components implemented using C#, HTML, and CSS.

Both client and server code are written in C#, allowing you to share code and libraries. Blazor can run your client-side C# code directly in the browser using WebAssembly. Because it's real .NET running on WebAssembly, you can re-use code and libraries from server-side parts of your application.

In this article, you will use Blazor Web Assembly to build the client side of the blog app.

What is Strapi?

Strapi is the leading open-source headless CMS based on Node.js to develop and manage content using Restful APIs and GraphQL.

With Strapi, we can scaffold our API faster and consume the content via APIs using any HTTP RESTful client or GraphQL-enabled front-end.

Back-end Setup

Step 1: Scaffold a Strapi project

Open up your terminal and create an empty project directory to store your project. This folder will serve as the root folder. The front-end and back-end code will be stored in subdirectories. I will name my project directory purplerhino.

$ mkdir purplerhino

Change the directory to the project directory purplerhino.

$ cd purplerhino

Enable source control for your project by initializing a git repository.

/purplerhino $ git init

Create a Strapi app.

/purplerhino $ npx create-strapi-app backend --quickstart

The command above will scaffold a new Strapi project in a directory named backend. The quickstart flag sets up your Strapi app with an SQLite database.

After successful installation, the Strapi app starts automatically. Open the Strapi Admin Registration interface from your web browser at localhost:1337/admin. Create the admin user for your Strapi application and click Let's Start.

Step 2: Build the Posts collection

Next, we will create a content-type that will store the details of each post.

We will create the content-type named posts containing the following fields: title, content, author, and image.

• Click Content-Type Builder on the left side of the page.
• Select + Create New Collection Type still at the left side of the page and fill in Post as the display name.
• Click on Continue to create a new Post collection.

We need to fill the Post collection with lots of post data. You can achieve this in two ways: using the Admin UI and using Strapi-generated API.

We will use the Admin UI to create a post.

• Click on Continue, which will present you with another modal to select fields for your Collection Type.

• Select Text and fill in title in the Text field.
• Click on + Add another field, select Rich Text, and name it content.
• Click on + Add another field and select Media field and name it image.
• Select + Add another field once again and select Text field and name it author.
• After adding all the required fields, click on ✓ Save to save the collection and wait for your Strapi server to restart.

• Click on Content Manager on the left of your dashboard. Under COLLECTION TYPES, select Post.
• Next, click on + Create new entry and add a few posts to your Posts collection. Click on Save and ✓ Publish for each post you add.

Step 3: Make Strapi API public

After successfully creating the Posts collection, it's time to allow public access to the collection because access will be denied if we try to access it with our public HTTP client.

• Click on Settings on the sidebar.
• In the USERS & PERMISSIONS PLUGIN section, click on Roles.
• On the Roles page, click on Public.

• Scroll down to the Permissions section:
• Select Post and check the Select all checkbox. This makes all the endpoints accessible to the public at localhost:1337/api/post
• Click on ✓ Save

Step 4: Install and enable the Transformer plugin

We will need to transform the JSON from the API request to work with our Blazor front-end. To do that, we will use Transformer by @ComfortablyCoding.

• Stop your Strapi server by pressing Ctrl + C on your keyboard.
• Install Transformer in the root folder of your Strapi app.

/purplerhino/backend $ npm install strapi-plugin-transformer

• Create a plugins.js file in the config folder to configure your plugin.

/purplerhino/backend $ touch config/plugins.js

• Add this configuration to ./config/plugins.js.

1module.exports = ({ env }) => ({
2 'transformer': {
3    enabled: true,
4    config: {
5      prefix: '/api/',
6      responseTransforms: {
7        removeAttributesKey: true,
8        removeDataKey: true,
9      }
10    }
11  },
12});

This configuration will provide an API response that will work with the setup of your Blazor front-end app.

• Rebuild your Strapi app and start your server for the changes to take effect.

1/purplerhino/backend $ yarn build
2/purplerhino/backend $ yarn develop

Front-end Setup

Step 5: Setting up the Blazor project

Let's set up our Blazor front-end app using the .NET command-line interface (CLI) to execute commands.

Open up your terminal and run the following commands:

1/purplerhino $ dotnet new blazorwasm -o frontend
2/purplerhino $ cd frontend
3/purplerhino/frontend $ dotnet run

Open localhost:5024 in your browser to see the Blazor frontend app.

Step 6: Integrate Strapi API with Blazor App

Your Blazor project is now set; the next step is to create the blog front-end.

To access the posts, you will have to use the Strapi API URL, which is localhost:1337/api.

In the frontend/wwwroot folder, create a file called appsettings.json to store the Strapi API URL.

/purplerhino/frontend $ touch wwwroot/appsettings.json

Add the following code to appsettings.json:

1{
2    "AppSettings": {
3    "STRAPI_API_URL": "http://localhost:1337" 
4    }
5}

Create a folder called Models and create a file called AppSettings.cs inside it.

1/purplerhino/frontend $ mkdir Models
2/purplerhino/frontend $ touch Models/AppSettings.cs

Add the following code to Models/AppSettings.cs:

1// ./Models/AppSettings.cs
2
3namespace frontend.Models
4{
5    public class AppSettings
6    {
7        public string STRAPI_API_URL { get; set; }
8    }
9}

Now open the Program.cs file and the code below. This is required to read the data from the appsettings.json file from anywhere in the application.

1// ./Program.cs
2
3using Microsoft.AspNetCore.Components.WebAssembly.Hosting;
4using Microsoft.Extensions.Configuration;
5using Microsoft.Extensions.DependencyInjection;
6using frontend.Models;
7using System;
8using System.Net.Http;
9using System.Threading.Tasks;
10
11namespace frontend
12{
13    public class Program
14    {
15        public static async Task Main(string[] args)
16        {
17            var builder = WebAssemblyHostBuilder.CreateDefault(args);
18            builder.RootComponents.Add<App>("#app");
19
20            builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });
21
22            await builder.Build().RunAsync();
23        }
24
25        public static void ConfigureServices(IServiceCollection services)
26        {
27            // Example of loading a configuration as configuration isn't available yet at this stage.
28            services.AddSingleton(provider =>
29            {
30                var config = provider.GetService<IConfiguration>();
31                return config.GetSection("App").Get<AppSettings>();
32            });
33        }
34    }
35}

You have just set up the integration of the Strapi API with the Blazor app. The next step is to create a component for your blog application.

Step 7: Display all blog posts on the home page

We use Tailwind CSS to style our awesome blog. So open the index.html file in the wwwroot folder and add this HTML snippet within the <head></head> section.

<link href="https://unpkg.com/tailwindcss@^2/dist/tailwind.min.css" rel="stylesheet">

Now open the Pages/Index.razor file and replace the existing code with the code below to show all the posts fetched from Strapi into your client app:

1@* ./Pages/Index.razor *@
2
3@page "/"
4@inject HttpClient Http
5@using Microsoft.Extensions.Configuration;
6@using Models
7@inject IConfiguration Configuration
8
9@if (allPosts == null)
10{
11    <p><em>Loading...</em></p>
12}
13else
14{
15    <section class="text-gray-600 body-font">
16    <div class="container px-5 py-4 mx-auto">
17        <div class="text-center mb-20">
18            <h1 class="sm:text-3xl text-2xl font-medium title-font text-gray-900 mb-4">Strapi Blazor Blog App</h1>
19            <p class="text-base leading-relaxed xl:w-2/4 lg:w-3/4 mx-auto text-gray-500s">British History - From the Anglo-Saxon era to present day Britain.</p>
20            <div class="flex mt-6 justify-center">
21                <div class="w-16 h-1 rounded-full bg-indigo-500 inline-flex"></div>
22            </div>
23        </div>
24        <div class="flex flex-wrap -m-3">
25            @foreach (var post in allPosts.data)
26                {
27                    <div class="xl:w-1/4 md:w-1/2 p-4">
28                        <div class="bg-gray-100 p-6 rounded-lg">
29                            <img class="h-40 rounded w-full object-cover object-center mb-6" src="@post.Image.Url"
30                        alt="content">
31                            <h2 class="text-lg text-gray-900 font-medium title-font mb-4">@post.Title</h2>
32                            <NavLink href="@($"post/{post.Id.ToString()}")">
33                                <a class="text-indigo-500 inline-flex items-center">
34                                    Read More
35                                    <svg fill="none" stroke="currentColor" stroke-linecap="round" stroke-linejoin="round"
36                                stroke-width="2" class="w-4 h-4 ml-2" viewBox="0 0 24 24">
37                                        <path d="M5 12h14M12 5l7 7-7 7"></path>
38                                    </svg>
39                                </a>
40                            </NavLink>
41                        </div>
42                    </div>
43                }
44            </div>
45        </div>
46    </section>
47}
48
49
50@code {
51    private PostList allPosts = null;
52    public string strapi_api_url;
53
54    protected override async Task OnInitializedAsync()
55    {
56        strapi_api_url = Configuration["AppSettings:STRAPI_API_URL"];
57        var url = "{STRAPI_API_URL}/api/posts?populate=*";
58        allPosts = await Http.GetFromJsonAsync<PostList>(url.Replace("{STRAPI_API_URL}", strapi_api_url));
59        if (allPosts.data != null)
60        {
61            foreach (var post in allPosts.data)
62            {
63                post.Image.Url = strapi_api_url + post.Image.Url;
64            }
65        }
66    }
67
68    public class Post
69    {
70        public int Id { get; set; }
71        public string Title { get; set; }
72        public string Content { get; set; }
73        public string Author { get; set; }
74        public Image Image { get; set; }
75    }
76
77    public class Image
78    {
79        public string Url { get; set; }
80    }
81
82    public class PostList
83    {
84        public List<Post> data { get; set; }
85    }
86
87}

Here's a brief explanation of what the code does:

• The top section from @pageto @inject is a list of all libraries Index.razor needs to use to fetch data from the Strapi API.
• The next section @if (allPosts == null) down to </section>} is the HTML required to render the posts from the Strapi API. The @foreach will loop through all the posts and retrieve the image, title, and id of each post and display each post on its card.
• The @code section is C# code. Post, Image, and PostList are classes that we will use to map the JSON data from the API response. allPosts is an instance of PostList. The JSON data from the url will be parsed into allPosts using the Http.GetFromJsonAsync() function. The @foreach loop will retrieve the URLs of each post's image.

Update the Shared/NavMenu.razor file to remove the extra menu from the sidebar. Replace the existing code with the following code:

1@* ./Shared/NavMenu.razor *@
2
3<header class="text-gray-600 body-font">
4    <div class="container mx-auto flex flex-wrap p-5 flex-col md:flex-row items-center">
5        <a class="flex order-first lg:order-none lg:w-1/5 title-font font-medium items-center text-gray-900 lg:items-center lg:justify-center mb-4 md:mb-0">
6            <img src="/blazor_strapi_logo.png" alt="logo" style="height:60px" />
7            <span class="ml-3 text-3xl">StrapiBlazorBlog</span>
8        </a>
9    </div>
10</header>

Update Shared/MainLayout.razor file as below:

1@* ./Shared/MainLayout.razor *@
2
3@inherits LayoutComponentBase
4
5<div>
6<NavMenu />
7
8<div>
9    @Body
10</div>
11</div>

Now run the application and navigate to localhost:5024 in your browser.

Wow 👌 We successfully displayed all our posts on the home page.

Step 8: Display a single blog post

We have managed to display all the posts on one page, but each post doesn't have its page, and the Read more button on the home page doesn't work too. Let's fix this.

Create a file called PostDetails.razor in the Pages folder.

/purplerhino/frontend $ touch Pages/PostDetails.razor

Add the following code to PostDetails.razor:

1@* ./Pages/PostDetails.razor *@
2
3@page "/post/{Id}"
4@inject HttpClient Http
5@inject NavigationManager NavigationManager
6@using System.Text.Json.Serialization
7@using Microsoft.Extensions.Configuration;
8@using Models
9@inject IConfiguration Configuration
10
11@if (postDetails == null)
12{
13    <p><em>Loading...</em></p>
14}
15else
16{
17    <section class="text-gray-700 body-font">
18        <div class="container mx-auto flex px-5 pb-24 items-center justify-center flex-col">
19            <h1 class="title-font sm:text-4xl text-3xl mb-4 font-medium text-gray-900">@postDetails.Data.Title</h1>
20            <img class=" mb-10 object-cover object-center rounded" alt="hero" src="@postDetails.Data.Image.Url" style="height:400px;width:900px">
21            <div class=" w-full">
22                <div class="mb-8 leading-relaxed">@((MarkupString)postDetails.Data.Content)</div>
23            </div>
24            <div class="p-2 w-full">
25                <button class="flex mx-auto text-white bg-indigo-500 border-0 py-2 px-8 focus:outline-none hover:bg-indigo-600 rounded text-lg" @onclick="NavigateToIndexComponent">Back</button>
26            </div>
27        </div>
28    </section>
29}
30
31@code {
32    [Parameter] public string Id { get; set; }
33
34    private PostSingle postDetails = null;
35
36    public string strapi_api_url;
37
38    protected override async Task OnInitializedAsync()
39    {
40
41        strapi_api_url = Configuration["AppSettings:STRAPI_API_URL"];
42        var url = "{STRAPI_API_URL}/api/posts/{Id}?populate=*";
43        url = url.Replace("{STRAPI_API_URL}", strapi_api_url);
44        url = url.Replace("{Id}", Id);
45        postDetails = await Http.GetFromJsonAsync<PostSingle>(url);
46
47        if (postDetails.Data != null)
48        {
49            postDetails.Data.Image.Url = strapi_api_url + postDetails.Data.Image.Url;
50        }
51    }
52
53    private void NavigateToIndexComponent()
54    {
55        NavigationManager.NavigateTo("");
56    }
57
58    public class PostSingle
59    {
60        public Data Data { get; set; }
61    }
62     public class Data
63    {
64        public int Id { get; set; }
65        public string Title { get; set; }
66        public string Content { get; set; }
67        public string Author { get; set; }
68        public Image Image { get; set; }
69    }
70
71    public class Image
72    {
73        public string Url { get; set; }
74    }
75
76}

Here's a brief explanation of what the code does.

• @page "/post/{Id}" refers to the URL of the page to be rendered based on the Id of the post
• @if (postDetaills == null) to </section> is the markup for rendering the page and uses the post's title, image and content retrieved from the Strapi API.
• @code section contains the classes to populate the data from the Strapi API just like in Index.razor, except that the API request is for a single post, not all the posts.

Now rerun the app and click on the Read More button for any post. You will see the full blog post on its own page.

Here’s a short video demo of how the blog will look like:

Step 9: Deploy the blog app

The Strapi backend API and our Blazor frontend app working, and the next step is to deploy your application. Among the options available, you can deploy Strapi API on Heroku. To deploy a Blazor WebAssembly app on Netlify, check out "How to Deploy a Blazor App on Netlify".

Conclusion

This article demonstrated how to build a simple blog application using Blazor as the front-end and Strapi as the back-end. Strapi has lots of integration with other frameworks. Check out the Strapi blog for more interesting tutorials showcasing Strapi's capabilities.

You can download the source code implementation from Github. Let me know if you have any comments, queries, or suggestions. The Strapi Team is always available to assist you.