Crie um website de notícias sobre criptomoedas em C# usando o Microsoft Azure App Service e o MongoDB Atlas

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@* The `page` attribute defines how this page can be opened. *@
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@page "/news"
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@* The `MongoDB` driver will be used to connect to your Atlas cluster. *@
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@using MongoDB.Driver
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@* `BSON` is a file format similar to JSON. MongoDB Atlas documents are BSON documents. *@
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@using MongoDB.Bson
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@* You need to add the `Data` folder as well. This is where the `News` class resides. *@
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@using CryptoNewsApp.Data
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@using Microsoft.AspNetCore.Builder
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@* The page title is what your browser tab will be called.  *@
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<PageTitle>News</PageTitle>
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@* Let's add a header to the page. *@
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<h1>News</h1>
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@* And then some data. *@
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@* This is just a simple table contains news and their date. *@
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@if (_news != null)
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{
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    <table class="table">
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        <thead>
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        <tr>
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            <th>News</th>
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            <th>Date</th>
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        </tr>
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        </thead>
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        <tbody>
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        @* Blazor takes this data from the `_news` field that we will fill later on. *@
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        @foreach (var newsEntry in _news)
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        {
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            <tr>
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                <td>@newsEntry.Title</td>
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                <td>@newsEntry.Date</td>
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            </tr>
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        }
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        </tbody>
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    </table>
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}
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@* This part defines the code that will be run when the page is loaded. It's basically  *@
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@* what would usually be PHP in a non-Blazor environment. *@
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@code {
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    // The `_news` field will hold all our news. We will have a look at the `News`
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    // class in just a moment.
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    private List<News>? _news;
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    // `OnInitializedAsync()` gets called when the website is loaded. Our data
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    // retrieval logic has to be placed here.
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    protected override async Task OnInitializedAsync()
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    {
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        // First, we need to create a `MongoClient` which is what we use to
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        // connect to our cluster.
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        // The only argument we need to pass on is the connection string you
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        // retrieved from Atlas. Make sure to replace the password placeholder with your password.
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        var mongoClient = new MongoClient("YOUR_CONNECTION_STRING");
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        // Using the `mongoCLient` we can now access the database.
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        var cryptoNewsDatabase = mongoClient.GetDatabase("crypto-news-database");
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        // Having a handle to the database we can furthermore get the collection data.
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        // Note that this is a generic function that takes `News` as it's parameter
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        // to define who the documents in this collection look like.
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        var newsCollection = cryptoNewsDatabase.GetCollection<News>("news");
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        // Having access to the collection, we issue a `Find` call to find all documents.
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        // A `Find` takes a filter as an argument. This filter is written as a `BsonDocument`.
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        // Remember, `BSON` is really just a (binary) JSON.
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        // Since we don't want to filter anything and get all the news, we pass along an
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        // empty / new `BsonDocument`. The result is then transformed into a list with `ToListAsync()`.
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        _news = await newsCollection.Find(new BsonDocument()).Limit(10).ToListAsync();
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        // And that's it! It's as easy as that using the driver to access the data
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        // in your MongoDB Atlas cluster.
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    }
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}

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using MongoDB.Bson;
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using MongoDB.Bson.Serialization.Attributes;
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namespace CryptoNewsApp.Data
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{
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    public class News
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    {
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        // The attribute `BsonId` signals the MongoDB driver that this field 
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        // should used to map the `_id` from the Atlas document.
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        // Remember to use the type `ObjectId` here as well.
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        [BsonId] public ObjectId Id { get; set; }
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        // The two other fields in each news are `title` and `date`.
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        // Since the C# coding style differs from the Atlas naming style, we have to map them.
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        // Thankfully there is another handy attribute to achieve this: `BsonElement`.
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        // It takes the document field's name and maps it to the classes field name.
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        [BsonElement("title")] public String Title { get; set; }
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        [BsonElement("date")] public DateTime Date { get; set; }
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    }
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}