From dfd97b2c3c372cf6619eddd35bcfcbc28634797d Mon Sep 17 00:00:00 2001
From: Roger Far <roger@versluis.ca>
Date: Fri, 5 Jan 2024 11:57:30 -0700
Subject: [PATCH] Add BASE_PATH environment variable for the base path setting.

---
 .../Middleware/BaseHrefMiddleware.cs              | 15 +++++++--------
 server/RdtClient.Web/Program.cs                   |  6 ++++--
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/server/RdtClient.Service/Middleware/BaseHrefMiddleware.cs b/server/RdtClient.Service/Middleware/BaseHrefMiddleware.cs
index 6477c49..54b5bba 100644
--- a/server/RdtClient.Service/Middleware/BaseHrefMiddleware.cs
+++ b/server/RdtClient.Service/Middleware/BaseHrefMiddleware.cs
@@ -1,19 +1,20 @@
 using System.Text.RegularExpressions;
 using Microsoft.AspNetCore.Http;
-using RdtClient.Data.Models.Internal;
 
 namespace RdtClient.Service.Middleware;
 
 public class BaseHrefMiddleware
 {
     private readonly RequestDelegate _next;
+    private readonly String _basePath;
 
-    public BaseHrefMiddleware(RequestDelegate next)
+    public BaseHrefMiddleware(RequestDelegate next, String basePath)
     {
         _next = next;
+        _basePath = $"/{basePath.TrimStart('/').TrimEnd('/')}/";
     }
 
-    public async Task InvokeAsync(HttpContext context, AppSettings appSettings)
+    public async Task InvokeAsync(HttpContext context)
     {
         var originalBody = context.Response.Body;
 
@@ -32,12 +33,10 @@ public class BaseHrefMiddleware
             // ReSharper disable once ConditionalAccessQualifierIsNonNullableAccordingToAPIContract
             if (context.Response.ContentType?.Contains("text/html") == true)
             {
-                var basePath = $"/{appSettings.BasePath!.TrimStart('/').TrimEnd('/')}/";
+                responseBody = Regex.Replace(responseBody, @"<base href=""/""", @$"<base href=""{_basePath}""");
                 
-                responseBody = Regex.Replace(responseBody, @"<base href=""/""", @$"<base href=""{basePath}""");
-                
-                responseBody = Regex.Replace(responseBody, "(<script.*?src=\")(.*?)(\".*?</script>)", $"$1{basePath}$2$3");
-                responseBody = Regex.Replace(responseBody, "(<link.*?href=\")(.*?)(\".*?>)", $"$1{basePath}$2$3");
+                responseBody = Regex.Replace(responseBody, "(<script.*?src=\")(.*?)(\".*?</script>)", $"$1{_basePath}$2$3");
+                responseBody = Regex.Replace(responseBody, "(<link.*?href=\")(.*?)(\".*?>)", $"$1{_basePath}$2$3");
 
                 context.Response.Headers.Remove("Content-Length");
                 await context.Response.WriteAsync(responseBody);
diff --git a/server/RdtClient.Web/Program.cs b/server/RdtClient.Web/Program.cs
index 585a52b..cc69adb 100644
--- a/server/RdtClient.Web/Program.cs
+++ b/server/RdtClient.Web/Program.cs
@@ -164,9 +164,11 @@ try
         }
     });
 
-    if (!String.IsNullOrWhiteSpace(appSettings.BasePath))
+    var basePath = !String.IsNullOrWhiteSpace(appSettings.BasePath) ? appSettings.BasePath : !String.IsNullOrWhiteSpace(Environment.GetEnvironmentVariable("BASE_PATH")) ? Environment.GetEnvironmentVariable("BASE_PATH") : null;
+
+    if (basePath != null)
     {
-        app.UseMiddleware<BaseHrefMiddleware>();
+        app.UseMiddleware<BaseHrefMiddleware>(basePath);
     }
 
     app.UseMiddleware<RequestLoggingMiddleware>();