From 94c94bd223e56242253c0b730205c68a31e545b3 Mon Sep 17 00:00:00 2001
From: Mariia Skripchenko <61115099+marychatte@users.noreply.github.com>
Date: Thu, 5 Dec 2024 16:12:01 +0100
Subject: [PATCH] KTOR-7893 Add favicon to Swagger UI (#4528)

---
 .../api/ktor-server-swagger.api               |  2 +
 .../io/ktor/server/plugins/swagger/Swagger.kt |  7 ++-
 .../server/plugins/swagger/SwaggerConfig.kt   |  7 ++-
 .../server/plugins/swagger/SwaggerTest.kt     | 49 ++++++++++++++++++-
 4 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/ktor-server/ktor-server-plugins/ktor-server-swagger/api/ktor-server-swagger.api b/ktor-server/ktor-server-plugins/ktor-server-swagger/api/ktor-server-swagger.api
index 66b98aec931..984357117c8 100644
--- a/ktor-server/ktor-server-plugins/ktor-server-swagger/api/ktor-server-swagger.api
+++ b/ktor-server/ktor-server-plugins/ktor-server-swagger/api/ktor-server-swagger.api
@@ -1,8 +1,10 @@
 public final class io/ktor/server/plugins/swagger/SwaggerConfig {
 	public fun <init> ()V
 	public final fun customStyle (Ljava/lang/String;)V
+	public final fun getFaviconLocation ()Ljava/lang/String;
 	public final fun getPackageLocation ()Ljava/lang/String;
 	public final fun getVersion ()Ljava/lang/String;
+	public final fun setFaviconLocation (Ljava/lang/String;)V
 	public final fun setPackageLocation (Ljava/lang/String;)V
 	public final fun setVersion (Ljava/lang/String;)V
 }
diff --git a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/Swagger.kt b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/Swagger.kt
index 5da6578617d..fd072c163e4 100644
--- a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/Swagger.kt
+++ b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/Swagger.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2022 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
+ * Copyright 2014-2024 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
 package io.ktor.server.plugins.swagger
@@ -86,6 +86,11 @@ public fun Route.swaggerUI(
                     config.customStyle?.let {
                         link(href = it, rel = "stylesheet")
                     }
+                    link(
+                        href = config.faviconLocation,
+                        rel = "icon",
+                        type = "image/x-icon"
+                    )
                 }
                 body {
                     div { id = "swagger-ui" }
diff --git a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/SwaggerConfig.kt b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/SwaggerConfig.kt
index a69ced719d3..3bb020086a2 100644
--- a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/SwaggerConfig.kt
+++ b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/src/io/ktor/server/plugins/swagger/SwaggerConfig.kt
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014-2022 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
+ * Copyright 2014-2024 JetBrains s.r.o and contributors. Use of this source code is governed by the Apache 2.0 license.
  */
 
 package io.ktor.server.plugins.swagger
@@ -28,4 +28,9 @@ public class SwaggerConfig {
      * Swagger package location
      */
     public var packageLocation: String = "https://unpkg.com/swagger-ui-dist"
+
+    /**
+     * Swagger favicon location
+     */
+    public var faviconLocation: String = "https://unpkg.com/swagger-ui-dist@$version/favicon-32x32.png"
 }
diff --git a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/test/io/ktor/server/plugins/swagger/SwaggerTest.kt b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/test/io/ktor/server/plugins/swagger/SwaggerTest.kt
index 473e20d9ff6..e1be3a61d0e 100644
--- a/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/test/io/ktor/server/plugins/swagger/SwaggerTest.kt
+++ b/ktor-server/ktor-server-plugins/ktor-server-swagger/jvm/test/io/ktor/server/plugins/swagger/SwaggerTest.kt
@@ -8,7 +8,8 @@ import io.ktor.client.request.*
 import io.ktor.client.statement.*
 import io.ktor.http.*
 import io.ktor.server.testing.*
-import kotlin.test.*
+import kotlin.test.Test
+import kotlin.test.assertEquals
 
 class SwaggerTest {
     @Test
@@ -25,6 +26,7 @@ class SwaggerTest {
               <head>
                 <title>Swagger UI</title>
                 <link href="https://unpkg.com/swagger-ui-dist@5.17.12/swagger-ui.css" rel="stylesheet">
+                <link href="https://unpkg.com/swagger-ui-dist@5.17.12/favicon-32x32.png" rel="icon" type="image/x-icon">
               </head>
               <body>
                 <div id="swagger-ui"></div>
@@ -65,6 +67,7 @@ class SwaggerTest {
               <head>
                 <title>Swagger UI</title>
                 <link href="https://unpkg.com/swagger-ui-dist@5.17.12/swagger-ui.css" rel="stylesheet">
+                <link href="https://unpkg.com/swagger-ui-dist@5.17.12/favicon-32x32.png" rel="icon" type="image/x-icon">
               </head>
               <body>
                 <div id="swagger-ui"></div>
@@ -101,4 +104,48 @@ class SwaggerTest {
         assertEquals("text/yaml; charset=UTF-8", response.contentType().toString())
         assertEquals("hello:\n  world".filter { it.isLetterOrDigit() }, body.filter { it.isLetterOrDigit() })
     }
+
+    @Test
+    fun testCustomFavicon() = testApplication {
+        routing {
+            swaggerUI("swagger") {
+                faviconLocation = "https://www.google.com/favicon.ico"
+            }
+        }
+
+        val response = client.get("/swagger") {
+            parameter("docExpansion", "list")
+        }.bodyAsText()
+        assertEquals(
+            """
+            <!DOCTYPE html>
+            <html>
+              <head>
+                <title>Swagger UI</title>
+                <link href="https://unpkg.com/swagger-ui-dist@5.17.12/swagger-ui.css" rel="stylesheet">
+                <link href="https://www.google.com/favicon.ico" rel="icon" type="image/x-icon">
+              </head>
+              <body>
+                <div id="swagger-ui"></div>
+                <script src="https://unpkg.com/swagger-ui-dist@5.17.12/swagger-ui-bundle.js" crossorigin="anonymous"></script>
+                <script src="https://unpkg.com/swagger-ui-dist@5.17.12/swagger-ui-standalone-preset.js" crossorigin="anonymous"></script>
+                <script>window.onload = function() {
+                window.ui = SwaggerUIBundle({
+                    url: '/swagger/documentation.yaml',
+                    dom_id: '#swagger-ui',
+                    presets: [
+                        SwaggerUIBundle.presets.apis,
+                        SwaggerUIStandalonePreset
+                    ],
+                    layout: 'StandaloneLayout',
+                    docExpansion: 'list'
+                });
+            }</script>
+              </body>
+            </html>
+            
+            """.trimIndent(),
+            response
+        )
+    }
 }