How to send automatic emails in aspnet core? - asp.net-core

Question

I would like to send automatic email notifications to users after 30 days of inactivity.
For now i can send them manually (one by one), but this is time consuming.
How can i do it automatically, in the background?
Aspnet Core 6.0 C# + Bootstrap 5 + SQL Server

Answer 1

In my humble opinion, you need a trigger to help query inactive users and sent email to them at times. And I used to use Azure function time trigger to do it. And here's my test for your scenario.
Firstly, I have to expose API which is used to query the inactive users, and another one is used to send email.
public string sendEmail(string emailAddress) {
return "send to "+ emailAddress + " successfully";
}
public string queryInactive() {
return "user1#xx.com";
}
Then creating an Azure function time trigger to set it triggered every 9 am. Then write code to let the function call these 2 apis.
#r "Newtonsoft.Json"
using System;
using System.Net;
using System.Text;
using System.IO;
using System.IO.Compression;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Primitives;
using Newtonsoft.Json;
public static void Run(TimerInfo myTimer, ILogger log)
{
log.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}");
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://xxxx/home/queryInactive");
request.Method = "GET";
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
Stream myResponseStream = response.GetResponseStream();
StreamReader reader = new StreamReader(myResponseStream, Encoding.UTF8);
String userAddress = reader.ReadToEnd();
log.LogInformation(userAddress);
HttpWebRequest request2 = (HttpWebRequest)WebRequest.Create("https://xxxx/home/sendEmail?emailAddress="+userAddress);
request.Method = "GET";
HttpWebResponse response2 = (HttpWebResponse)request2.GetResponse();
Stream myResponseStream2 = response2.GetResponseStream();
StreamReader reader2 = new StreamReader(myResponseStream2, Encoding.UTF8);
String responseString = reader2.ReadToEnd();
log.LogInformation(responseString);
}
And this is my test result.