add subdomain rewrite rule (#336)

4 files changed, 37 insertions, 2 deletions

diff --git a/src/StardewModdingAPI.Web/Controllers/ModsController.cs b/src/StardewModdingAPI.Web/Controllers/ModsController.cs
index 876f5248..7f7afbb9 100644
--- a/src/StardewModdingAPI.Web/Controllers/ModsController.cs
+++ b/src/StardewModdingAPI.Web/Controllers/ModsController.cs
@@ -9,7 +9,7 @@ using StardewModdingAPI.Web.Models;
 namespace StardewModdingAPI.Web.Controllers
 {
     /// <summary>Provides an API to perform mod update checks.</summary>
-    [Route("v1.0/mods")]
+    [Route("api/v1.0/mods")]
     [Produces("application/json")]
     public class ModsController : Controller
     {
diff --git a/src/StardewModdingAPI.Web/Framework/RewriteSubdomainRule.cs b/src/StardewModdingAPI.Web/Framework/RewriteSubdomainRule.cs
new file mode 100644
index 00000000..9b89cb65
--- /dev/null
+++ b/src/StardewModdingAPI.Web/Framework/RewriteSubdomainRule.cs
@@ -0,0 +1,30 @@
+using System;
+using Microsoft.AspNetCore.Rewrite;
+
+namespace StardewModdingAPI.Web.Framework
+{
+    /// <summary>Rewrite requests to prepend the subdomain portion (if any) to the path.</summary>
+    /// <remarks>Derived from <a href="https://stackoverflow.com/a/44526747/262123" />.</remarks>
+    public class RewriteSubdomainRule : IRule
+    {
+        /// <summary>Applies the rule. Implementations of ApplyRule should set the value for <see cref="RewriteContext.Result" /> (defaults to RuleResult.ContinueRules).</summary>
+        /// <param name="context">The rewrite context.</param>
+        public void ApplyRule(RewriteContext context)
+        {
+            context.Result = RuleResult.ContinueRules;
+
+            // get host parts
+            string host = context.HttpContext.Request.Host.Host;
+            string[] parts = host.Split('.');
+
+            // validate
+            if (parts.Length < 2)
+                return;
+            if (parts.Length < 3 && !"localhost".Equals(parts[1], StringComparison.InvariantCultureIgnoreCase))
+                return;
+
+            // prepend to path
+            context.HttpContext.Request.Path = $"/{parts[0]}{context.HttpContext.Request.Path}";
+        }
+    }
+}
diff --git a/src/StardewModdingAPI.Web/StardewModdingAPI.Web.csproj b/src/StardewModdingAPI.Web/StardewModdingAPI.Web.csproj
index 7dff3fb6..2af7c3df 100644
--- a/src/StardewModdingAPI.Web/StardewModdingAPI.Web.csproj
+++ b/src/StardewModdingAPI.Web/StardewModdingAPI.Web.csproj
@@ -7,6 +7,7 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore" Version="2.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.0.0" />
+    <PackageReference Include="Microsoft.AspNetCore.Rewrite" Version="2.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.StaticFiles" Version="2.0.0" />
     <PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="2.0.0" />
     <PackageReference Include="Pathoschild.Http.FluentClient" Version="3.1.0" />
diff --git a/src/StardewModdingAPI.Web/Startup.cs b/src/StardewModdingAPI.Web/Startup.cs
index b35d072b..19dffb88 100644
--- a/src/StardewModdingAPI.Web/Startup.cs
+++ b/src/StardewModdingAPI.Web/Startup.cs
@@ -1,9 +1,11 @@
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Rewrite;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
+using StardewModdingAPI.Web.Framework;
 
 namespace StardewModdingAPI.Web
 {
@@ -53,7 +55,9 @@ namespace StardewModdingAPI.Web
         {
             loggerFactory.AddConsole(this.Configuration.GetSection("Logging"));
             loggerFactory.AddDebug();
-            app.UseMvc();
+            app
+                .UseRewriter(new RewriteOptions().Add(new RewriteSubdomainRule())) // convert subdomain.smapi.io => smapi.io/subdomain for routing
+                .UseMvc();
         }
     }
 }