Merge pull request #26143 from abpframework/maliming/blazor-logo-pathbase

Resolve `IBrandingProvider` urls in the Blazor themes

docs/en/framework/ui/blazor/branding.md

@@ -41,4 +41,12 @@ The result will be like shown below:
 * `LogoUrl`: A URL to show the application logo.
 * `LogoReverseUrl`: A URL to show the application logo on a reverse color theme (dark, for example).
 
+ABP's built-in Blazor themes resolve these URLs for the current application. `logo.png`, `/logo.png` and `~/logo.png` all mean the same application relative URL and include the base path of the application, so they keep working when it is deployed to a non-root path, like an IIS virtual directory. A URL that already contains the path gets it twice. External URLs are used as they are. `LogoReverseUrl` is used by the themes that have a dark style, like LeptonX, and falls back to `LogoUrl`.
+
+> **Note**: The `<base href>` of the host page has to match the path the application is served from, like `<base href="/myapp/" />`.
+
+A logo that the project defines in its own CSS is not resolved. The LeptonX Lite startup templates set the logo that way, so remove that declaration to deploy them to a non-root path.
+
+To resolve a branding URL in a custom theme or component, use `NavigationManager.ResolveBrandingUrl(...)` with `@using Volo.Abp.AspNetCore.Components.Web.Theming.Branding`, or `ResolveBrandingCssUrl(...)` when it is rendered into `url('...')` in CSS.
+
 > **Tip**: `IBrandingProvider` is used in every page refresh. For a multi-tenant application, you can return a tenant specific application name to customize it per tenant.

docs/en/framework/ui/mvc-razor-pages/branding.md

@@ -43,9 +43,11 @@ The result will be like shown below:
 * `LogoUrl`: A URL to show the application logo.
 * `LogoReverseUrl`: A URL to show the application logo on a reverse color theme (dark, for example).
 
-ABP's built-in MVC themes resolve the branding URLs for the current request. `/logo.png`, `logo.png` and `~/logo.png` are treated as application relative URLs and include the `PathBase` of the request, so they keep working when the application is deployed to a non-root path, like an IIS virtual directory. Absolute HTTP(S) URLs, like `https://cdn.example.com/logo.png`, and protocol relative URLs, like `//cdn.example.com/logo.png`, are returned unchanged. `null` and white space values are treated as not set.
+ABP's built-in MVC themes resolve these URLs for the current request. `logo.png`, `/logo.png` and `~/logo.png` all mean the same application relative URL and include the `PathBase` of the request, so they keep working when the application is deployed to a non-root path, like an IIS virtual directory. A URL that already contains the path gets it twice. External URLs are used as they are. `LogoReverseUrl` is used by the themes that have a dark style, like LeptonX, and falls back to `LogoUrl`.
 
-If you render a branding URL in a custom MVC theme or view, resolve it with `Url.ResolveBrandingUrl(...)`.
+A logo that the project defines in its own CSS is not resolved. The LeptonX Lite startup templates set the logo that way, so remove that declaration to deploy them to a non-root path.
+
+To resolve a branding URL in a custom theme or view, use `Url.ResolveBrandingUrl(...)` with `@using Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared.Branding`, or `Url.ResolveBrandingCssUrl(...)` when it is rendered into `url('...')` in CSS.
 
 > **Tip**: `IBrandingProvider` is used in every page refresh. For a multi-tenant application, you can return a tenant specific application name to customize it per tenant.
 
@@ -80,7 +82,7 @@ Both properties return `null` by default and follow the same URL rules as `LogoU
 
 The active theme decides whether and where to use the compact logo. The LeptonX MVC theme enables its compact branding when `LogoIconUrl` is not empty: it uses the compact logo instead of the full logo in its branding areas and shows `AppName` next to it where there is room for both. Dark and dim styles use `LogoIconReverseUrl` and fall back to `LogoIconUrl` when it is not set. Themes that don't support `IBrandingLogoProvider` ignore these properties.
 
-> This URL resolution and the compact logo apply to the ASP.NET Core MVC / Razor Pages themes. The Blazor themes handle branding on their own.
+> The compact logo applies to the ASP.NET Core MVC / Razor Pages themes. The Blazor themes resolve the branding URLs by the same rules, see [Blazor UI: Branding](../blazor/branding.md).
 
 ## Overriding the Branding Area
 

framework/src/Volo.Abp.AspNetCore.Components.Web.Theming/Branding/NavigationManagerBrandingExtensions.cs

@@ -0,0 +1,52 @@
+using System;
+using Microsoft.AspNetCore.Components;
+using Volo.Abp.Ui.Branding;
+
+namespace Volo.Abp.AspNetCore.Components.Web.Theming.Branding;
+
+public static class NavigationManagerBrandingExtensions
+{
+    /// <summary>
+    /// Resolves a branding url of <see cref="IBrandingProvider"/>: "logo.svg", "/logo.svg" and
+    /// "~/logo.svg" all keep working under a non-root base path.
+    /// </summary>
+    public static string? ResolveBrandingUrl(this NavigationManager navigationManager, string? url)
+    {
+        Check.NotNull(navigationManager, nameof(navigationManager));
+
+        if (url.IsNullOrWhiteSpace())
+        {
+            return null;
+        }
+
+        var brandingUrl = url!.Trim();
+
+        if (BrandingUrlHelper.IsExternalUrl(brandingUrl))
+        {
+            return brandingUrl;
+        }
+
+        var applicationRelativeUrl = BrandingUrlHelper.RemoveApplicationRelativePrefix(brandingUrl);
+        var baseUri = new Uri(navigationManager.BaseUri);
+
+        // "/http://host/logo.svg" would silently lose its host when only the path is taken.
+        if (BrandingUrlHelper.IsExternalUrl(applicationRelativeUrl) ||
+            !Uri.TryCreate(baseUri, applicationRelativeUrl, out var absoluteUrl) ||
+            absoluteUrl.GetLeftPart(UriPartial.Authority) != baseUri.GetLeftPart(UriPartial.Authority))
+        {
+            return brandingUrl;
+        }
+
+        return absoluteUrl.PathAndQuery + absoluteUrl.Fragment;
+    }
+
+    /// <summary>
+    /// Same as <see cref="ResolveBrandingUrl"/>, escaped for url('...') in css.
+    /// </summary>
+    public static string? ResolveBrandingCssUrl(this NavigationManager navigationManager, string? url)
+    {
+        var resolvedUrl = navigationManager.ResolveBrandingUrl(url);
+
+        return resolvedUrl == null ? null : BrandingUrlHelper.EscapeCssValue(resolvedUrl);
+    }
+}

framework/src/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared/Branding/UrlHelperBrandingExtensions.cs

@@ -1,16 +1,14 @@
 using System;
 using Microsoft.AspNetCore.Mvc;
+using Volo.Abp.Ui.Branding;
 
 namespace Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared.Branding;
 
 public static class UrlHelperBrandingExtensions
 {
     /// <summary>
-    /// Resolves a branding url of <see cref="Volo.Abp.Ui.Branding.IBrandingProvider"/> for the current request.
+    /// Resolves a branding url of <see cref="IBrandingProvider"/>: "logo.svg", "/logo.svg" and
-    /// "logo.svg", "/logo.svg" and "~/logo.svg" all mean the same application relative url and keep working
+    /// "~/logo.svg" all keep working under a non-root <see cref="Microsoft.AspNetCore.Http.HttpRequest.PathBase"/>.
-    /// under a non-root <see cref="Microsoft.AspNetCore.Http.HttpRequest.PathBase"/>.
-    /// External urls ("http://", "https://" and "//host/") are returned as they are.
-    /// Returns null when <paramref name="url"/> is null or white space.
     /// </summary>
     public static string? ResolveBrandingUrl(this IUrlHelper urlHelper, string? url)
     {
@@ -19,22 +17,31 @@ public static class UrlHelperBrandingExtensions
             return null;
         }
 
-        if (IsExternalUrl(url!))
+        var brandingUrl = url!.Trim();
+
+        if (BrandingUrlHelper.IsExternalUrl(brandingUrl))
         {
-            return url;
+            return brandingUrl;
         }
 
-        var applicationRelativeUrl = url!.StartsWith("~/", StringComparison.Ordinal)
+        var relativeUrl = BrandingUrlHelper.RemoveApplicationRelativePrefix(brandingUrl);
-            ? url
+
-            : "~/" + url.TrimStart('/');
+        // "/http://host/logo.svg" would become a local path that does not exist.
+        if (BrandingUrlHelper.IsExternalUrl(relativeUrl))
+        {
+            return brandingUrl;
+        }
 
-        return urlHelper.Content(applicationRelativeUrl);
+        return urlHelper.Content("~/" + relativeUrl);
     }
 
-    private static bool IsExternalUrl(string url)
+    /// <summary>
+    /// Same as <see cref="ResolveBrandingUrl"/>, escaped for url('...') in css.
+    /// </summary>
+    public static string? ResolveBrandingCssUrl(this IUrlHelper urlHelper, string? url)
     {
-        return url.StartsWith("http://", StringComparison.OrdinalIgnoreCase)
+        var resolvedUrl = urlHelper.ResolveBrandingUrl(url);
-               || url.StartsWith("https://", StringComparison.OrdinalIgnoreCase)
+
-               || url.StartsWith("//", StringComparison.Ordinal);
+        return resolvedUrl == null ? null : BrandingUrlHelper.EscapeCssValue(resolvedUrl);
     }
 }

framework/src/Volo.Abp.UI/Volo/Abp/Ui/Branding/BrandingUrlHelper.cs

@@ -0,0 +1,69 @@
+using System;
+
+namespace Volo.Abp.Ui.Branding;
+
+public static class BrandingUrlHelper
+{
+    // "//host/" and any url with a scheme are used as they are, the others are application relative.
+    public static bool IsExternalUrl(string? url)
+    {
+        if (url.IsNullOrWhiteSpace())
+        {
+            return false;
+        }
+
+        var brandingUrl = url!.Trim();
+
+        return brandingUrl.StartsWith("//", StringComparison.Ordinal) || HasScheme(brandingUrl);
+    }
+
+    public static string RemoveApplicationRelativePrefix(string url)
+    {
+        return url.StartsWith("~/", StringComparison.Ordinal)
+            ? url.Substring(2)
+            : url.TrimStart('/');
+    }
+
+    // Rendered into url('...') inside a style element and must not be able to end either of them.
+    public static string EscapeCssValue(string url)
+    {
+        return url
+            .Replace("\\", "\\\\")
+            .Replace("'", "\\'")
+            .Replace("<", "%3C")
+            .Replace("\r", string.Empty)
+            .Replace("\n", string.Empty)
+            .Replace("\f", string.Empty);
+    }
+
+    // A broken value like "http://[" also has a scheme, so it is matched here instead of by Uri.TryCreate.
+    private static bool HasScheme(string url)
+    {
+        var schemeLength = url.IndexOf(':');
+        if (schemeLength < 1 || !IsLetter(url[0]))
+        {
+            return false;
+        }
+
+        for (var i = 1; i < schemeLength; i++)
+        {
+            var character = url[i];
+            if (!IsLetter(character) && !IsDigit(character) && character != '+' && character != '-' && character != '.')
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private static bool IsLetter(char character)
+    {
+        return (character >= 'a' && character <= 'z') || (character >= 'A' && character <= 'Z');
+    }
+
+    private static bool IsDigit(char character)
+    {
+        return character >= '0' && character <= '9';
+    }
+}

framework/test/Volo.Abp.AspNetCore.Components.Web.Theming.Tests/Volo/Abp/AspNetCore/Components/Web/Theming/Branding/NavigationManagerBrandingExtensions_Tests.cs

@@ -0,0 +1,143 @@
+using Microsoft.AspNetCore.Components;
+using Shouldly;
+using Xunit;
+
+namespace Volo.Abp.AspNetCore.Components.Web.Theming.Branding;
+
+public class NavigationManagerBrandingExtensions_Tests
+{
+    [Theory]
+    [InlineData("logo.svg")]
+    [InlineData("/logo.svg")]
+    [InlineData("~/logo.svg")]
+    public void Should_Treat_All_Local_Formats_As_Application_Relative(string url)
+    {
+        CreateNavigationManager("https://localhost/").ResolveBrandingUrl(url)
+            .ShouldBe("/logo.svg");
+
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl(url)
+            .ShouldBe("/myapp/logo.svg");
+    }
+
+    // Keep in sync with the same test of the mvc themes.
+    [Theory]
+    [InlineData("logo.svg", "/myapp/logo.svg")]
+    [InlineData("/logo.svg", "/myapp/logo.svg")]
+    [InlineData("~/logo.svg", "/myapp/logo.svg")]
+    [InlineData("images/logo.svg?v=42", "/myapp/images/logo.svg?v=42")]
+    [InlineData("images/logo.svg#brand", "/myapp/images/logo.svg#brand")]
+    [InlineData("https://cdn.example.com/logo.svg", "https://cdn.example.com/logo.svg")]
+    [InlineData("//cdn.example.com/logo.svg", "//cdn.example.com/logo.svg")]
+    [InlineData("data:image/svg+xml;base64,PHN2Zy8+", "data:image/svg+xml;base64,PHN2Zy8+")]
+    [InlineData("http://[", "http://[")]
+    [InlineData("https://", "https://")]
+    [InlineData("http://a b", "http://a b")]
+    [InlineData("  ~/logo.svg  ", "/myapp/logo.svg")]
+    [InlineData(" https://cdn.example.com/logo.svg ", "https://cdn.example.com/logo.svg")]
+    [InlineData("/http://cdn.example.com/logo.svg", "/http://cdn.example.com/logo.svg")]
+    [InlineData("~/http://cdn.example.com/logo.svg", "~/http://cdn.example.com/logo.svg")]
+    public void Should_Resolve_The_Same_As_The_Mvc_Themes(string url, string expected)
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl(url)
+            .ShouldBe(expected);
+    }
+
+    [Theory]
+    [InlineData("images/../logo.svg", "/myapp/logo.svg")]
+    [InlineData("images/../../logo.svg", "/logo.svg")]
+    public void Should_Resolve_A_Dot_Segment(string url, string expected)
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl(url).ShouldBe(expected);
+    }
+
+    [Fact]
+    public void Should_Not_Resolve_A_Url_That_Points_To_Another_Host()
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl("/http://cdn.example.com/logo.svg")
+            .ShouldBe("/http://cdn.example.com/logo.svg");
+    }
+
+    [Fact]
+    public void Should_Escape_A_Form_Feed_In_Css()
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingCssUrl("data:image/svg+xml,\u000C<svg/>")
+            .ShouldBe("data:image/svg+xml,%3Csvg/>");
+    }
+
+    [Fact]
+    public void Should_Keep_Query_And_Fragment()
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl("~/images/logo.svg?v=42")
+            .ShouldBe("/myapp/images/logo.svg?v=42");
+
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl("images/logo.svg#brand")
+            .ShouldBe("/myapp/images/logo.svg#brand");
+    }
+
+    [Theory]
+    [InlineData("http://cdn.example.com/logo.svg")]
+    [InlineData("https://cdn.example.com/logo.svg")]
+    [InlineData("//cdn.example.com/logo.svg")]
+    [InlineData("data:image/svg+xml;base64,PHN2Zy8+")]
+    [InlineData("http://[")]
+    [InlineData("https://")]
+    [InlineData("http://a b")]
+    public void Should_Return_External_Urls_As_They_Are(string url)
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl(url)
+            .ShouldBe(url);
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    public void Should_Return_Null_When_Url_Is_Empty(string? url)
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingUrl(url)
+            .ShouldBeNull();
+    }
+
+    [Fact]
+    public void Should_Escape_Css_Breaking_Characters()
+    {
+        CreateNavigationManager("https://localhost/myapp/")
+            .ResolveBrandingCssUrl("data:image/svg+xml,<svg/>')</style><script>alert(1)</script>")
+            .ShouldBe("data:image/svg+xml,%3Csvg/>\\')%3C/style>%3Cscript>alert(1)%3C/script>");
+    }
+
+    [Fact]
+    public void Should_Escape_Backslashes_And_Drop_Line_Breaks()
+    {
+        CreateNavigationManager("https://localhost/myapp/")
+            .ResolveBrandingCssUrl("data:image/svg+xml,a\\b\r\nc")
+            .ShouldBe("data:image/svg+xml,a\\\\bc");
+    }
+
+    [Fact]
+    public void Should_Resolve_And_Escape_Application_Relative_Urls()
+    {
+        CreateNavigationManager("https://localhost/myapp/")
+            .ResolveBrandingCssUrl("~/images/logo.svg")
+            .ShouldBe("/myapp/images/logo.svg");
+    }
+
+    [Fact]
+    public void Should_Return_Null_From_Css_Overload_When_Url_Is_Empty()
+    {
+        CreateNavigationManager("https://localhost/myapp/").ResolveBrandingCssUrl("   ").ShouldBeNull();
+    }
+
+    private static NavigationManager CreateNavigationManager(string baseUri)
+    {
+        return new TestNavigationManager(baseUri);
+    }
+
+    private class TestNavigationManager : NavigationManager
+    {
+        public TestNavigationManager(string baseUri)
+        {
+            Initialize(baseUri, baseUri);
+        }
+    }
+}

framework/test/Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared.Tests/Volo/Abp/AspNetCore/Mvc/UI/Theme/Shared/Branding/UrlHelperBrandingExtensions_Tests.cs

@@ -0,0 +1,110 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Abstractions;
+using Microsoft.AspNetCore.Mvc.Routing;
+using Microsoft.AspNetCore.Routing;
+using Shouldly;
+using Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared.Branding;
+using Xunit;
+
+namespace Volo.Abp.AspNetCore.Mvc.UI.Theme.Shared.Branding;
+
+public class UrlHelperBrandingExtensions_Tests
+{
+    private readonly IUrlHelper _urlHelper;
+
+    public UrlHelperBrandingExtensions_Tests()
+    {
+        var httpContext = new DefaultHttpContext {
+            Request = { PathBase = "/myapp" }
+        };
+
+        _urlHelper = new UrlHelper(new ActionContext(httpContext, new RouteData(), new ActionDescriptor()));
+    }
+
+    [Theory]
+    [InlineData("logo.svg")]
+    [InlineData("/logo.svg")]
+    [InlineData("~/logo.svg")]
+    public void Should_Treat_All_Local_Formats_As_Application_Relative(string url)
+    {
+        _urlHelper.ResolveBrandingUrl(url).ShouldBe("/myapp/logo.svg");
+    }
+
+    // Keep in sync with the same test of the blazor themes.
+    [Theory]
+    [InlineData("logo.svg", "/myapp/logo.svg")]
+    [InlineData("/logo.svg", "/myapp/logo.svg")]
+    [InlineData("~/logo.svg", "/myapp/logo.svg")]
+    [InlineData("images/logo.svg?v=42", "/myapp/images/logo.svg?v=42")]
+    [InlineData("images/logo.svg#brand", "/myapp/images/logo.svg#brand")]
+    [InlineData("https://cdn.example.com/logo.svg", "https://cdn.example.com/logo.svg")]
+    [InlineData("//cdn.example.com/logo.svg", "//cdn.example.com/logo.svg")]
+    [InlineData("data:image/svg+xml;base64,PHN2Zy8+", "data:image/svg+xml;base64,PHN2Zy8+")]
+    [InlineData("http://[", "http://[")]
+    [InlineData("https://", "https://")]
+    [InlineData("http://a b", "http://a b")]
+    [InlineData("  ~/logo.svg  ", "/myapp/logo.svg")]
+    [InlineData(" https://cdn.example.com/logo.svg ", "https://cdn.example.com/logo.svg")]
+    [InlineData("/http://cdn.example.com/logo.svg", "/http://cdn.example.com/logo.svg")]
+    [InlineData("~/http://cdn.example.com/logo.svg", "~/http://cdn.example.com/logo.svg")]
+    public void Should_Resolve_The_Same_As_The_Blazor_Themes(string url, string expected)
+    {
+        _urlHelper.ResolveBrandingUrl(url).ShouldBe(expected);
+    }
+
+    [Fact]
+    public void Should_Keep_A_Dot_Segment_Of_An_Application_Relative_Url()
+    {
+        _urlHelper.ResolveBrandingUrl("images/../logo.svg").ShouldBe("/myapp/images/../logo.svg");
+    }
+
+    [Fact]
+    public void Should_Escape_A_Form_Feed_In_Css()
+    {
+        _urlHelper.ResolveBrandingCssUrl("data:image/svg+xml,\u000C<svg/>")
+            .ShouldBe("data:image/svg+xml,%3Csvg/>");
+    }
+
+    [Fact]
+    public void Should_Keep_Query_And_Fragment()
+    {
+        _urlHelper.ResolveBrandingUrl("~/images/logo.svg?v=42").ShouldBe("/myapp/images/logo.svg?v=42");
+        _urlHelper.ResolveBrandingUrl("images/logo.svg#brand").ShouldBe("/myapp/images/logo.svg#brand");
+    }
+
+    [Theory]
+    [InlineData("http://cdn.example.com/logo.svg")]
+    [InlineData("https://cdn.example.com/logo.svg")]
+    [InlineData("//cdn.example.com/logo.svg")]
+    [InlineData("data:image/svg+xml;base64,PHN2Zy8+")]
+    [InlineData("http://[")]
+    [InlineData("https://")]
+    [InlineData("http://a b")]
+    public void Should_Return_External_Urls_As_They_Are(string url)
+    {
+        _urlHelper.ResolveBrandingUrl(url).ShouldBe(url);
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    public void Should_Return_Null_When_Url_Is_Empty(string? url)
+    {
+        _urlHelper.ResolveBrandingUrl(url).ShouldBeNull();
+    }
+
+    [Fact]
+    public void Should_Escape_Css_Breaking_Characters()
+    {
+        _urlHelper.ResolveBrandingCssUrl("data:image/svg+xml,<svg/>')</style>")
+            .ShouldBe("data:image/svg+xml,%3Csvg/>\\')%3C/style>");
+    }
+
+    [Fact]
+    public void Should_Resolve_And_Escape_Application_Relative_Urls()
+    {
+        _urlHelper.ResolveBrandingCssUrl("~/images/logo.svg").ShouldBe("/myapp/images/logo.svg");
+    }
+}

framework/test/Volo.Abp.UI.Navigation.Tests/Volo/Abp/Ui/Branding/BrandingUrlHelper_Tests.cs

@@ -0,0 +1,49 @@
+using Shouldly;
+using Xunit;
+
+namespace Volo.Abp.Ui.Branding;
+
+public class BrandingUrlHelper_Tests
+{
+    [Theory]
+    [InlineData("//cdn.example.com/logo.svg")]
+    [InlineData("https://cdn.example.com/logo.svg")]
+    [InlineData("data:image/svg+xml;base64,PHN2Zy8+")]
+    [InlineData("blob:1234")]
+    [InlineData(" https://cdn.example.com/logo.svg ")]
+    [InlineData("http://[")]
+    public void Should_Detect_External_Urls(string url)
+    {
+        BrandingUrlHelper.IsExternalUrl(url).ShouldBeTrue();
+    }
+
+    [Theory]
+    [InlineData(null)]
+    [InlineData("")]
+    [InlineData("   ")]
+    [InlineData("logo.svg")]
+    [InlineData("/logo.svg")]
+    [InlineData("~/logo.svg")]
+    [InlineData("/images/a:b.svg")]
+    [InlineData("1st:logo.svg")]
+    public void Should_Not_Detect_Other_Urls_As_External(string? url)
+    {
+        BrandingUrlHelper.IsExternalUrl(url).ShouldBeFalse();
+    }
+
+    [Theory]
+    [InlineData("~/images/logo.svg", "images/logo.svg")]
+    [InlineData("/images/logo.svg", "images/logo.svg")]
+    [InlineData("images/logo.svg", "images/logo.svg")]
+    public void Should_Remove_The_Application_Relative_Prefix(string url, string expected)
+    {
+        BrandingUrlHelper.RemoveApplicationRelativePrefix(url).ShouldBe(expected);
+    }
+
+    [Fact]
+    public void Should_Escape_The_Characters_That_End_A_Css_Url_Or_A_Style_Element()
+    {
+        BrandingUrlHelper.EscapeCssValue("logo.svg\\')\r\n\f</style>")
+            .ShouldBe("logo.svg\\\\\\')%3C/style>");
+    }
+}

modules/basic-theme/src/Volo.Abp.AspNetCore.Components.Web.BasicTheme/Themes/Basic/Branding.razor

@@ -1,9 +1,16 @@
+@using Volo.Abp.AspNetCore.Components.Web.Theming.Branding
 @using Volo.Abp.Ui.Branding
 @inject IBrandingProvider BrandingProvider
+@inject NavigationManager NavigationManager
+
+@{
+    var logoUrl = NavigationManager.ResolveBrandingUrl(BrandingProvider.LogoUrl);
+}
+
 <a class="navbar-brand" href="">
-    @if (!BrandingProvider.LogoUrl.IsNullOrWhiteSpace())
+    @if (!logoUrl.IsNullOrWhiteSpace())
     {
-        <img src="@BrandingProvider.LogoUrl.TrimStart('/', '~')" alt="@BrandingProvider.AppName">
+        <img src="@logoUrl" alt="@BrandingProvider.AppName">
     }
     @BrandingProvider.AppName
 </a>