Merge pull request #3

Add Base62 encoding and refactor project structure

Author: joeyx712

.github/workflows/dotnet.yml

@@ -26,7 +26,7 @@ jobs:
       - name: Test
         run: dotnet test --no-build --verbosity normal
       - name: dotnet publish
-        run: dotnet publish UrlShortener.Api -c Release -o ${{env.DOTNET_ROOT}}/myapp
+        run: dotnet publish Api/src/UrlShortener.Api -c Release -o ${{env.DOTNET_ROOT}}/myapp
       - name: Upload artifact for deployment job
         uses: actions/upload-artifact@v4
         with:

Api/src/UrlShortener.Api.Core/Base62EncodingExtensions.cs

@@ -0,0 +1,24 @@
+namespace UrlShortener.Api.Core;
+
+public static class Base62EncodingExtensions
+{
+    private const string Alphanumeric =
+        "0123456789" +
+        "ABCDEFGHIJKLMNOPQRSTUVWXYZ" +
+        "abcdefghijklmnopqrstuvwxyz";
+    
+    public static string EncodeToBase62(this long number)
+    {
+        if (number == 0) return Alphanumeric[0].ToString();
+        
+        var result = new Stack<char>();
+        while (number > 0)
+        {
+            result.Push(Alphanumeric[(int)(number % 62)]);
+            number /= 62;
+        }
+        
+        return new string(result.ToArray());
+    }
+    
+}

Api/src/UrlShortener.Api.Core/ShortUrlGenerator.cs

@@ -0,0 +1,16 @@
+namespace UrlShortener.Api.Core;
+
+public class ShortUrlGenerator
+{
+    private readonly TokenProvider _tokenProvider;
+
+    public ShortUrlGenerator(TokenProvider tokenProvider)
+    {
+        _tokenProvider = tokenProvider;
+    }
+
+    public string GenerateUniqueUrl()
+    {
+        return _tokenProvider.GetToken().EncodeToBase62();
+    }
+}

Api/src/UrlShortener.Api.Core/TokenProvider.cs

@@ -0,0 +1,28 @@
+namespace UrlShortener.Api.Core;
+
+public class TokenProvider
+{
+    private readonly object _tokenLock = new();
+
+    private long _token = 0;
+    private TokenRange? _tokenRange;
+
+    public void AssignRange(int start, int end)
+    {
+        AssignRange(new TokenRange(start, end));
+    }
+
+    public void AssignRange(TokenRange tokenRange)
+    {
+        _tokenRange = tokenRange;
+        _token = tokenRange.Start;
+    }
+
+    public long GetToken()
+    {
+        lock (_tokenLock)
+        {
+            return _token++;
+        }
+    }
+}

Api/src/UrlShortener.Api.Core/TokenRange.cs

@@ -0,0 +1,3 @@
+namespace UrlShortener.Api.Core;
+
+public record TokenRange(long Start, long End);

Api/src/UrlShortener.Api.Core/UrlShortener.Api.Core.csproj

@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>net9.0</TargetFramework>
+        <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+</Project>