allow http favicon + non png in config

closes #167

build.gradle.kts

@@ -72,6 +72,7 @@ dependencies {
 
     implementation("com.google.guava:guava:30.1.1-jre")
     implementation("com.velocitypowered:velocity-native:3.0.0")
+    implementation("net.coobird:thumbnailator:0.4.14")
     implementation("org.powernukkit.fastutil:fastutil-lite:8.1.1")
     implementation("org.yaml:snakeyaml:1.29")
 

src/main/kotlin/com/viaversion/aas/config/VIAaaSConfig.kt

@@ -2,8 +2,11 @@ package com.viaversion.aas.config
 
 import com.viaversion.aas.secureRandom
 import com.viaversion.viaversion.util.Config
+import net.coobird.thumbnailator.Thumbnails
+import java.io.ByteArrayOutputStream
 import java.io.File
 import java.net.URI
+import java.net.URL
 import java.util.*
 
 object VIAaaSConfig : Config(File("config/viaaas.yml")) {
@@ -11,6 +14,26 @@ object VIAaaSConfig : Config(File("config/viaaas.yml")) {
         reloadConfig()
     }
 
+    override fun reloadConfig() {
+        super.reloadConfig()
+        reloadIcon()
+    }
+
+    fun reloadIcon() {
+        val rawUrl = this.getString("favicon-url", "")!!
+        faviconUrl = when {
+            rawUrl.isEmpty() -> null
+            rawUrl.startsWith("data:image/png;base64,") -> rawUrl.filter { !it.isWhitespace() }
+            else -> "data:image/png;base64," + Base64.getEncoder().encodeToString(
+                ByteArrayOutputStream().also {
+                    Thumbnails.of(URL(rawUrl))
+                        .size(64, 64)
+                        .outputFormat("png").toOutputStream(it)
+                }.toByteArray()
+            )
+        }
+    }
+
     override fun getUnsupportedOptions() = emptyList<String>()
     override fun getDefaultConfigURL() = VIAaaSConfig::class.java.classLoader.getResource("viaaas.yml")!!
     override fun handleConfig(map: MutableMap<String, Any>) {
@@ -63,8 +86,7 @@ object VIAaaSConfig : Config(File("config/viaaas.yml")) {
             if (it.isNullOrBlank()) throw IllegalStateException("invalid jwt-secret") else it
         }
     val rateLimitLoginMc: Double get() = this.getDouble("rate-limit-login-mc", 0.2)
-    val faviconUrl: String?
-        get() = this.getString("favicon-url", "")!!.filter { !it.isWhitespace() }.ifEmpty { null }
+    var faviconUrl: String? = null
     val maxPlayers: Int? get() = this.getInt("max-players", 20).let { if (it == -1) null else it }
     val backendProxy: URI?
         get() = this.getString("backend-proxy", "").let { if (it.isNullOrEmpty()) null else URI.create(it) }

src/main/resources/viaaas.yml

@@ -75,8 +75,8 @@ listening-ws-limit: 10
 #####
 # Misc
 #####
-# Favicon URL to use in disconnection messages. Should use "data:image/png;base64," and be a 64x64 PNG
-favicon-url: ''
+# Favicon URL to use in disconnection messages.
+favicon-url: https://cdn.discordapp.com/attachments/316218802155028482/850014925622476820/unknown.png
 # Requires online mode for front-end connections. May be useful for stopping bots.
 force-online-mode: false
 # Max players to allow connection. Use -1 to not limit