refactor: align Xray config JSON fields

Author: whalechoi

app/src/main/kotlin/engine/xray/CustomXrayConfigRewriter.kt

@@ -53,10 +53,10 @@ private fun JsonObject.overwriteAsteriskInboundDns(
         ),
     )
 
-    return updatedWithout(setOf("fakedns")) {
+    return updatedWithout(setOf("fakedns", "fakeDns")) {
         put("inbounds", request.inbounds.toJsonObjectArray())
         put("dns", buildXrayDnsConfig(dnsPlan))
-        putIfNotNull("fakedns", dnsPlan.fakeDns)
+        putIfNotNull("fakeDns", dnsPlan.fakeDns)
         put("outbounds", outboundsRewrite.outbounds)
         put("routing", routing)
     }

app/src/main/kotlin/engine/xray/GeneratedXrayConfig.kt

@@ -7,7 +7,6 @@ import kotlinx.serialization.json.JsonArray
 import kotlinx.serialization.json.JsonElement
 import kotlinx.serialization.json.JsonObject
 import kotlinx.serialization.json.buildJsonObject
-import kotlinx.serialization.json.put
 
 internal data class GeneratedXrayConfig(
     val log: JsonObject,
@@ -26,7 +25,7 @@ internal data class GeneratedXrayConfig(
             put("inbounds", inbounds)
             put("outbounds", outbounds)
             routing?.let { put("routing", it) }
-            fakeDns?.let { put("fakedns", it) }
+            fakeDns?.let { put("fakeDns", it) }
             observatory?.let { put("observatory", it) }
             burstObservatory?.let { put("burstObservatory", it) }
         }

app/src/main/kotlin/engine/xray/XrayOutboundJson.kt

@@ -53,7 +53,7 @@ internal fun buildXrayObservatory(selectors: List<String>): JsonObject? {
     if (selectors.isEmpty()) return null
     return buildJsonObject {
         put("subjectSelector", selectors.distinct().toJsonStringArray())
-        put("probeUrl", XrayObservatoryProbeUrl)
+        put("probeURL", XrayObservatoryProbeUrl)
         put("probeInterval", "3m")
         put("enableConcurrency", true)
     }

app/src/main/kotlin/features/proxy/server/model/XrayOutbound.kt

@@ -9,8 +9,10 @@ import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.JsonElement
 import kotlinx.serialization.json.JsonObject
 import kotlinx.serialization.json.JsonObjectBuilder
+import kotlinx.serialization.json.JsonPrimitive
 import kotlinx.serialization.json.add
 import kotlinx.serialization.json.buildJsonObject
+import kotlinx.serialization.json.contentOrNull
 import kotlinx.serialization.json.put
 import kotlinx.serialization.json.putJsonArray
 import kotlinx.serialization.json.putJsonObject
@@ -143,12 +145,10 @@ private fun JsonObjectBuilder.putRawSettings(params: V2RayParameters) {
 
 private fun JsonObjectBuilder.putWsSettings(params: V2RayParameters) {
     putJsonObject("wsSettings") {
+        val transportHeaders = params.httpTransportHeaders("WebSocket headers")
         putIfNotBlank("path", params.path)
-        putIfNotBlank("host", params.host)
-        val headers = params.headers.toXrayJsonObjectOrNull("WebSocket headers")
-        if (headers != null) {
-            put("headers", headers)
-        }
+        putIfNotBlank("host", transportHeaders.host)
+        transportHeaders.headers?.let { put("headers", it) }
     }
 }
 
@@ -164,12 +164,10 @@ private fun JsonObjectBuilder.putGrpcSettings(params: V2RayParameters) {
 
 private fun JsonObjectBuilder.putHttpUpgradeSettings(params: V2RayParameters) {
     putJsonObject("httpupgradeSettings") {
+        val transportHeaders = params.httpTransportHeaders("HTTPUpgrade headers")
         putIfNotBlank("path", params.path)
-        putIfNotBlank("host", params.host)
-        val headers = params.headers.toXrayJsonObjectOrNull("HTTPUpgrade headers")
-        if (headers != null) {
-            put("headers", headers)
-        }
+        putIfNotBlank("host", transportHeaders.host)
+        transportHeaders.headers?.let { put("headers", it) }
     }
 }
 
@@ -203,3 +201,37 @@ private fun String?.toXrayJsonObjectOrNull(fieldName: String): JsonObject? {
     return element as? JsonObject
         ?: proxyValidationError(ProxyServerValidationError.JsonObjectRequired, fieldName)
 }
+
+private data class XrayHttpTransportHeaders(
+    val host: String?,
+    val headers: JsonObject?,
+)
+
+private fun V2RayParameters.httpTransportHeaders(fieldName: String): XrayHttpTransportHeaders {
+    val explicitHost = host?.trim()?.takeIf(String::isNotEmpty)
+    val parsedHeaders = headers.toXrayJsonObjectOrNull(fieldName)
+        ?: return XrayHttpTransportHeaders(host = explicitHost, headers = null)
+    var hostHeader: String? = null
+    val filteredHeaders = buildJsonObject {
+        parsedHeaders.forEach { (name, value) ->
+            if (name.equals("Host", ignoreCase = true)) {
+                if (hostHeader.isNullOrBlank()) {
+                    hostHeader = value.headerStringOrNull()
+                }
+            } else {
+                put(name, value)
+            }
+        }
+    }
+    return XrayHttpTransportHeaders(
+        host = explicitHost ?: hostHeader,
+        headers = filteredHeaders.takeIf { it.isNotEmpty() },
+    )
+}
+
+private fun JsonElement.headerStringOrNull(): String? {
+    return (this as? JsonPrimitive)
+        ?.contentOrNull
+        ?.trim()
+        ?.takeIf(String::isNotEmpty)
+}