PI06 i PI06-1. Docker definitions for MSSQL and Postgres. Data seeder/generator for countries and people. Entity Framework example with variants for Postgres and MSSQL

DefensiveProgramming/Logging/DataLoader.cs

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+using Microsoft.Extensions.Logging;
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Text.RegularExpressions;
+
+namespace Logging;
+
+public class DataLoader : IDataLoader
+{
+  private readonly ILogger<DataLoader> logger;
+
+  public DataLoader(ILogger<DataLoader> logger)
+  {
+    this.logger = logger;
+  }
+
+  public List<(string, DateOnly)> LoadData(string filename)
+  {
+    List<(string, DateOnly)> list = new();
+    if (!File.Exists(filename))
+    {
+      string message = $"File {filename} does not exist";
+      logger.LogError(message);
+      throw new FileNotFoundException(message);
+    }
+    else
+    {
+      //use File.ReadAllLines for small files
+      using (var reader = new StreamReader(File.OpenRead(filename)))
+      {
+        string? line;
+        while((line = reader.ReadLine()) != null) {
+          string pattern = "[0-3]?[0-9].[0-3]?[0-9].[0-9]{4}.";
+          var match = Regex.Match(line, pattern);
+          if (match.Success)
+          {
+            string datetext = line.Substring(match.Index, match.Length);
+            if (DateOnly.TryParseExact(datetext, "d.M.yyyy.", CultureInfo.InvariantCulture, DateTimeStyles.None, out DateOnly date))
+            {
+              var item = (line.Remove(match.Index, match.Length).Trim(), date);
+              logger.LogTrace(item.ToString());
+              list.Add(item);
+            }
+            else
+            {
+              logger.LogWarning("Invalid date in line: " + line);
+            }
+          }
+          else
+          {
+            logger.LogWarning("No date found in line: " + line);
+          }
+        }
+      }
+    }
+    return list;
+  }  
+}