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Exercise - Add a message to the queue

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Now that all the requirements are in place, you can write code that creates a new storage queue and adds a message. We would typically place this code in our front-end apps that generate the data.

Add code to send a message

The sample program contains a SendMessageAsync method. In this step, you write code to implement this method.

1. Open the Program.cs file in your code editor.

2. Locate the SendMessageAsync method.

3. Remove the line that throws a NotImplementedException.

4. Add the following code at the start of the SendMessageAsync method to get the details of the new article from the user.

   // Get input from user
   Console.WriteLine("Enter headline: ");
   string headline = Console.ReadLine();
   Console.WriteLine("Enter location: ");
   string location = Console.ReadLine();
   NewsArticle article = new NewsArticle() { Headline = headline, Location = location };
   

5. This code creates a NewsArticle object that we want to store in our queue. To do so, serialize the object to JSON and then use the SendMessageAsync method to send the message to our queue. Add this code into the SendMessageAsyc method after the line that instantiates a NewsArticle object.

   // Build and send the message to the queue
   string message = JsonSerializer.Serialize(article);
   Response<SendReceipt> response = await queueClient.SendMessageAsync(message);
   SendReceipt sendReceipt = response.Value;
   

6. Finally, we're going to print to the console some information about the SendReceipt that was included in the response from sending the message. For our application, these fields are purely informational, but could be used in an actual application to log or track data about the message submitted to the queue.

   Console.WriteLine($"Message sent. Message id={sendReceipt.MessageId}  Expiration time={sendReceipt.ExpirationTime}");
   Console.WriteLine();
   

   The SendMessageAsync method should look as follows when complete.

   static async Task SendMessageAsync(QueueClient queueClient)
   {
       // Get input from user
       Console.WriteLine("Enter headline: ");
       string headline = Console.ReadLine();
       Console.WriteLine("Enter location: ");
       string location = Console.ReadLine();
       NewsArticle article = new NewsArticle() { Headline = headline, Location = location };
   
       // Build and send the message to the queue
       string message = JsonSerializer.Serialize(article);
       Response<SendReceipt> response = await queueClient.SendMessageAsync(message);
       SendReceipt sendReceipt = response.Value;
   
       // Print out the send receipt
       Console.WriteLine($"Message sent. Message id={sendReceipt.MessageId}  Expiration time={sendReceipt.ExpirationTime}");
       Console.WriteLine();
   }
   

Execute the application

Now you're ready to build and run the program to send your first message to the queue.

1. Make sure that you save the file in the code editor, and then use the dotnet build command in the Cloud Shell to build the application.

   dotnet build
   

2. Run the application.

   dotnet run
   

3. When the application runs, choose option 1 to send a message, and then input a headline and location of your choice to send a message to the queue. When the menu appears again, you can use 'X' to exit the program.

   You should see the following output.

   What operation would you like to perform?
     1 - Send message
     2 - Peek at the next message
     3 - Receive message
     X - Exit program
   1
   
   Enter headline:
   World leaders to meet at economic summit
   Enter location:
   Paris, France
   Message sent. Message id=638160c9-f136-49b3-a06c-d2a45739fc4e  Expiration time=10/14/2021 3:49:42 PM +00:00
   
   What operation would you like to perform?
     1 - Send message
     2 - Peek at the next message
     3 - Receive message
     X - Exit program
   X    
   

Check your results

You can check queues in the Azure portal using the Azure CLI, or using Azure PowerShell. For this example, we use the Azure CLI to check the state of our queue.

Run the following command in the Cloud Shell environment.

az storage message peek --queue-name newsqueue --connection-string $MY_STORAGE_CONNECTION_STRING 

This command should output the information for your message, which looks something like this:

[
  {
    "content": "{\"Headline\":\"World leaders to meet at economic summit\",\"Location\":\"Paris, France\"}",
    "dequeueCount": 0,
    "expirationTime": "2021-10-14T15:49:42+00:00",
    "id": "638160c9-f136-49b3-a06c-d2a45739fc4e",
    "insertionTime": "2021-10-07T15:49:42+00:00",
    "popReceipt": null,
    "timeNextVisible": null
  }
]

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