Server: Verify HTTP method

Author: nonperforming

RhythmDoctor.CafeLink/RhythmDoctor.CafeLink.csproj

@@ -4,7 +4,7 @@
     <AssemblyName>io.github.nonperforming.cafelink</AssemblyName>
     <Product>RhythmDoctor.CafeLink</Product>
     <Description>Additional support for rhythm.cafe</Description>
-    <Version>1.0.0</Version>
+    <Version>1.0.1</Version>
     <LangVersion>latest</LangVersion>
     <RestoreAdditionalProjectSources>
       https://api.nuget.org/v3/index.json;

RhythmDoctor.CafeLink/Server/Handlers/ImportHandler.cs

@@ -1,8 +1,11 @@
-namespace RhythmDoctor.CafeLink.Server.Handlers;
+using System.Net.Http;
+
+namespace RhythmDoctor.CafeLink.Server.Handlers;
 
 internal class ImportHandler : IHandler
 {
   public string Endpoint => "import";
+  public HttpMethod AcceptedMethod => HttpMethod.Post;
 
   public IResponse HandleRequest(NameValueCollection parameters)
   {

RhythmDoctor.CafeLink/Server/Handlers/PlayHandler.cs

@@ -1,8 +1,11 @@
-namespace RhythmDoctor.CafeLink.Server.Handlers;
+using System.Net.Http;
+
+namespace RhythmDoctor.CafeLink.Server.Handlers;
 
 internal class PlayHandler : IHandler
 {
   public string Endpoint => "play";
+  public HttpMethod AcceptedMethod => HttpMethod.Post;
 
   public IResponse HandleRequest(NameValueCollection parameters)
   {

RhythmDoctor.CafeLink/Server/Handlers/StatusHandler.cs

@@ -1,10 +1,12 @@
-using System.Text;
+using System.Net.Http;
+using System.Text;
 
 namespace RhythmDoctor.CafeLink.Server.Handlers;
 
 internal class StatusHandler : IHandler
 {
   public string Endpoint => "status";
+  public HttpMethod AcceptedMethod => HttpMethod.Get;
 
   public IResponse HandleRequest(NameValueCollection parameters)
   {

RhythmDoctor.CafeLink/Server/Interfaces/IHandler.cs

@@ -1,8 +1,12 @@
-namespace RhythmDoctor.CafeLink.Server.Interfaces;
+using System.Net.Http;
+
+namespace RhythmDoctor.CafeLink.Server.Interfaces;
 
 internal interface IHandler
 {
   internal string Endpoint { get; }
 
+  HttpMethod AcceptedMethod { get; }
+
   internal IResponse HandleRequest(NameValueCollection parameters);
 }

RhythmDoctor.CafeLink/Server/Interfaces/IResponse.cs

@@ -1,4 +1,6 @@
-namespace RhythmDoctor.CafeLink.Server.Interfaces;
+using System.Net.Http;
+
+namespace RhythmDoctor.CafeLink.Server.Interfaces;
 
 public interface IResponse
 {

RhythmDoctor.CafeLink/Server/Responses/ErrorResponse.cs

@@ -1,4 +1,5 @@
-using System.Text;
+using System.Net.Http;
+using System.Text;
 
 namespace RhythmDoctor.CafeLink.Server.Responses;
 

RhythmDoctor.CafeLink/Server/Server.cs

@@ -1,4 +1,5 @@
-using System.Text;
+using System.Net.Http;
+using System.Text;
 
 namespace RhythmDoctor.CafeLink.Server;
 
@@ -98,9 +99,17 @@ private async Task HandleRequest()
     }
 
     Plugin.Logger.LogInfo($"[{nameof(Server)}] Handling '{endpoint}' request...");
-    response = _handlers.TryGetValue(endpoint, out IHandler handler)
-      ? handler.HandleRequest(httpContext.Request.QueryString)
-      : new ErrorResponse(HttpStatusCode.NotFound, "Unknown endpoint.");
+    if (_handlers.TryGetValue(endpoint, out IHandler handler))
+    {
+      response =
+        handler.AcceptedMethod.Method != httpRequest.HttpMethod
+          ? new ErrorResponse(HttpStatusCode.MethodNotAllowed, $"Expected {handler.AcceptedMethod.Method} method.")
+          : handler.HandleRequest(httpContext.Request.QueryString);
+    }
+    else
+    {
+      response = new ErrorResponse(HttpStatusCode.NotFound, "Unknown endpoint.");
+    }
 
     SendResponseWithDataAndGetReadyForNextRequest:
     IReadOnlyCollection<byte> data = response.Data;