KTOR-6850 Fix the query parameters object for each engine but Netty t… (

#4015)

* KTOR-6850 Fix the query parameters object for each engine but Netty to return an empty string for the query parameter without value

(cherry picked from commit 7c76fa7)

ktor-server/ktor-server-cio/jvmAndNix/src/io/ktor/server/cio/CIOApplicationRequest.kt

@@ -25,7 +25,7 @@ internal class CIOApplicationRequest(
 
     override val headers: Headers = CIOHeaders(request.headers)
 
-    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters) }
+    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters).toQueryParameters() }
 
     override val rawQueryParameters: Parameters by lazy {
         val uri = request.uri.toString()
@@ -47,6 +47,26 @@ internal class CIOApplicationRequest(
     }
 }
 
+/**
+ * Converts parameters to query parameters by fixing the [Parameters.get] method
+ * to make it return an empty string for the query parameter without value
+ */
+private fun Parameters.toQueryParameters(): Parameters {
+    val parameters = this
+    return object : Parameters {
+        override fun get(name: String): String? {
+            val values = getAll(name) ?: return null
+            return if (values.isEmpty()) "" else values.first()
+        }
+        override val caseInsensitiveName: Boolean
+            get() = parameters.caseInsensitiveName
+        override fun getAll(name: String): List<String>? = parameters.getAll(name)
+        override fun names(): Set<String> = parameters.names()
+        override fun entries(): Set<Map.Entry<String, List<String>>> = parameters.entries()
+        override fun isEmpty(): Boolean = parameters.isEmpty()
+    }
+}
+
 internal class CIOConnectionPoint(
     private val remoteNetworkAddress: NetworkAddress?,
     private val localNetworkAddress: NetworkAddress?,

ktor-server/ktor-server-servlet-jakarta/jvm/src/io/ktor/server/servlet/jakarta/ServletApplicationRequest.kt

@@ -17,7 +17,7 @@ public abstract class ServletApplicationRequest(
 
     override val local: RequestConnectionPoint = ServletConnectionPoint(servletRequest)
 
-    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters) }
+    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters).toQueryParameters() }
 
     override val rawQueryParameters: Parameters by lazy(LazyThreadSafetyMode.NONE) {
         val uri = servletRequest.queryString ?: return@lazy Parameters.Empty
@@ -29,3 +29,23 @@ public abstract class ServletApplicationRequest(
     @Suppress("LeakingThis") // this is safe because we don't access any content in the request
     override val cookies: RequestCookies = ServletApplicationRequestCookies(servletRequest, this)
 }
+
+/**
+ * Converts parameters to query parameters by fixing the [Parameters.get] method
+ * to make it return an empty string for the query parameter without value
+ */
+private fun Parameters.toQueryParameters(): Parameters {
+    val parameters = this
+    return object : Parameters {
+        override fun get(name: String): String? {
+            val values = getAll(name) ?: return null
+            return if (values.isEmpty()) "" else values.first()
+        }
+        override val caseInsensitiveName: Boolean
+            get() = parameters.caseInsensitiveName
+        override fun getAll(name: String): List<String>? = parameters.getAll(name)
+        override fun names(): Set<String> = parameters.names()
+        override fun entries(): Set<Map.Entry<String, List<String>>> = parameters.entries()
+        override fun isEmpty(): Boolean = parameters.isEmpty()
+    }
+}

ktor-server/ktor-server-servlet/jvm/src/io/ktor/server/servlet/ServletApplicationRequest.kt

@@ -17,7 +17,7 @@ public abstract class ServletApplicationRequest(
 
     override val local: RequestConnectionPoint = ServletConnectionPoint(servletRequest)
 
-    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters) }
+    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters).toQueryParameters() }
 
     override val rawQueryParameters: Parameters by lazy(LazyThreadSafetyMode.NONE) {
         val uri = servletRequest.queryString ?: return@lazy Parameters.Empty
@@ -29,3 +29,23 @@ public abstract class ServletApplicationRequest(
     @Suppress("LeakingThis") // this is safe because we don't access any content in the request
     override val cookies: RequestCookies = ServletApplicationRequestCookies(servletRequest, this)
 }
+
+/**
+ * Converts parameters to query parameters by fixing the [Parameters.get] method
+ * to make it return an empty string for the query parameter without value
+ */
+private fun Parameters.toQueryParameters(): Parameters {
+    val parameters = this
+    return object : Parameters {
+        override fun get(name: String): String? {
+            val values = getAll(name) ?: return null
+            return if (values.isEmpty()) "" else values.first()
+        }
+        override val caseInsensitiveName: Boolean
+            get() = parameters.caseInsensitiveName
+        override fun getAll(name: String): List<String>? = parameters.getAll(name)
+        override fun names(): Set<String> = parameters.names()
+        override fun entries(): Set<Map.Entry<String, List<String>>> = parameters.entries()
+        override fun isEmpty(): Boolean = parameters.isEmpty()
+    }
+}

ktor-server/ktor-server-test-host/jvmAndNix/src/io/ktor/server/testing/TestApplicationRequest.kt

@@ -90,7 +90,7 @@ public class TestApplicationRequest constructor(
      */
     var bodyChannel: ByteReadChannel = if (closeRequest) ByteReadChannel.Empty else ByteChannel()
 
-    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters) }
+    override val queryParameters: Parameters by lazy { encodeParameters(rawQueryParameters).toQueryParameters() }
 
     override val rawQueryParameters: Parameters by lazy {
         parseQueryString(queryString(), decode = false)
@@ -121,6 +121,26 @@ public class TestApplicationRequest constructor(
     override fun receiveChannel(): ByteReadChannel = bodyChannel
 }
 
+/**
+ * Converts parameters to query parameters by fixing the [Parameters.get] method
+ * to make it return an empty string for the query parameter without value
+ */
+private fun Parameters.toQueryParameters(): Parameters {
+    val parameters = this
+    return object : Parameters {
+        override fun get(name: String): String? {
+            val values = getAll(name) ?: return null
+            return if (values.isEmpty()) "" else values.first()
+        }
+        override val caseInsensitiveName: Boolean
+            get() = parameters.caseInsensitiveName
+        override fun getAll(name: String): List<String>? = parameters.getAll(name)
+        override fun names(): Set<String> = parameters.names()
+        override fun entries(): Set<Map.Entry<String, List<String>>> = parameters.entries()
+        override fun isEmpty(): Boolean = parameters.isEmpty()
+    }
+}
+
 /**
  * Sets an HTTP request body text content.
  */

ktor-server/ktor-server-test-suites/jvm/src/io/ktor/server/testing/suites/ContentTestSuite.kt

@@ -766,6 +766,19 @@ abstract class ContentTestSuite<TEngine : ApplicationEngine, TConfiguration : Ap
         }
     }
 
+    @Test
+    fun testAccessingQueryParameterWithoutValue() {
+        createAndStartServer {
+            get("/") {
+                call.respondText(call.request.queryParameters["auto"].toString())
+            }
+        }
+
+        withUrl("/?auto") {
+            assertEquals("", bodyAsText())
+        }
+    }
+
     companion object {
         const val classesDir: String = "build/classes/"
     }