+implemented automatic relogin on connection restore and better connection tracking.

README.md

@@ -26,7 +26,6 @@ fun Application.testServerModule() {
     superloginServer(TestApiServer<TestSession>(), { TestSession() }) {
         // This is a sample of your porvate API implementation:
         on(api.loginName) {
-            println("login name called. now we have $currentLoginName : $superloginData")
             currentLoginName
         }
     }

build.gradle.kts

@@ -9,7 +9,7 @@ val logback_version="1.2.10"
 
 
 group = "net.sergeych"
-version = "0.0.1-SNAPSHOT"
+version = "0.0.2-SNAPSHOT"
 
 repositories {
     mavenCentral()
@@ -49,7 +49,7 @@ kotlin {
             dependencies {
                 implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.3")
                 api("net.sergeych:unikrypto:1.2.2-SNAPSHOT")
-                api("net.sergeych:parsec3:0.3.3-SNAPSHOT")
+                api("net.sergeych:parsec3:0.4.0-SNAPSHOT")
                 api("net.sergeych:boss-serialization-mp:0.2.4-SNAPSHOT")
                 api("net.sergeych:unikrypto:1.2.2-SNAPSHOT")
             }
@@ -76,7 +76,7 @@ kotlin {
         val jsMain by getting
         val jsTest by getting
     }
-+    publishing {
+    publishing {
         repositories {
             maven {
                 url = uri("https://maven.universablockchain.com/")

src/commonMain/kotlin/net.sergeych.superlogin/WaitForState.kt

@@ -0,0 +1,39 @@
+package net.sergeych.superlogin
+
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.launch
+
+
+/**
+ * Wait for stateflow value to be accepted by the predicate that should
+ * return true. Does not wait if the predicate returns true for the
+ * current state value.
+ */
+suspend fun <T> StateFlow<T>.waitUntil(predicate: (T) -> Boolean) {
+    // Speed optimization:
+    if( predicate(value)) return
+    // we have to wait here
+    coroutineScope {
+        // first we watch the state change to avoid RCs:
+        val job = launch {
+            collect {
+                if (predicate(value)) cancel()
+            }
+        }
+        // now the value can be changed while we were starting up the
+        // job so another check is necessary before waiting for a job
+        if (!predicate(value)) job.join()
+        // created job should be cancelled anyway
+        if (job.isActive) job.cancel()
+    }
+}
+
+/**
+ * Wait for state flow to be equal to the expected value. Does not wait if it
+ * already so.
+ */
+suspend fun <T> StateFlow<T>.waitFor(state: T) {
+    waitUntil { it == state }
+}

src/commonMain/kotlin/net.sergeych.superlogin/client/SuperloginClient.kt

@@ -1,15 +1,16 @@
 package net.sergeych.superlogin.client
 
-import kotlinx.coroutines.*
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
+import kotlinx.coroutines.coroutineScope
+import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.serialization.Serializable
 import net.sergeych.boss_serialization.BossDecoder
 import net.sergeych.boss_serialization_mp.BossEncoder
-import net.sergeych.mp_logger.LogTag
+import net.sergeych.mp_logger.*
-import net.sergeych.mp_logger.Loggable
-import net.sergeych.mp_logger.exception
-import net.sergeych.mp_logger.warning
 import net.sergeych.mp_tools.globalLaunch
 import net.sergeych.parsec3.*
 import net.sergeych.superlogin.*
@@ -62,7 +63,6 @@ class SuperloginClient<D, S : WithAdapter>(
                     val v = _state.value
                     if (v !is LoginState.LoggedIn<*> || v.loginData != value) {
                         _state.value = LoginState.LoggedIn(value)
-                        if (!adapterReady.isCompleted) adapterReady.complete(Unit)
                     }
                 }
             }
@@ -71,20 +71,34 @@ class SuperloginClient<D, S : WithAdapter>(
     val applicationData: D?
         get() = (state.value as? LoginState.LoggedIn<D>)?.loginData?.data
 
-    private var adapterReady = CompletableDeferred<Unit>()
+    private var adapterReady = MutableStateFlow<Boolean>(false)
 
-    override suspend fun adapter(): Adapter<S> = transport.adapter()
+    /**
-//        do {
+     * The flow that tracks readiness state of the connetion adapter. In other works,
-//            try {
+     * when its value is false, [adapter] deferred is not completed and [call] method
-//                adapterReady.await()
+     * will wait until it is ready.
-//                return transport.adapter()
+     *
-//            } catch (x: Throwable) {
+     * The reason for it is as follows: when connetion drops,
-//                exception { "failed to get adapter" to x }
+     * superlogin client awaits its automatic restore (by parsec3) and then tries to re-login.
-//            }
+     * Until this login restore will finish either successful or not, calling parsec3 commands
-//        } while (true)
+     * may produce unpredictable results, so it is automatically postponed until login state
-//    }
+     * is restored. This is completely transparent to the caller, and this state flow allows
+     * client to be notified on actual connection state.
+     */
+    val connectionReady = adapterReady.asStateFlow()
 
+    override suspend fun adapter(): Adapter<S> {
+        adapterReady.waitFor(true)
+        return transport.adapter()
+    }
+
+    /**
+     * Call client API commands with it (uses [adapter] under the hood)
+     */
     suspend fun <A, R> call(ca: CommandDescriptor<A, R>, args: A): R = adapter().invokeCommand(ca, args)
+    /**
+     * Call client API commands with it (uses [adapter] under the hood)
+     */
     suspend fun <R> call(ca: CommandDescriptor<Unit, R>): R = adapter().invokeCommand(ca)
 
     private suspend fun <A, R> invoke(ca: CommandDescriptor<A, R>, args: A): R =
@@ -98,20 +112,26 @@ class SuperloginClient<D, S : WithAdapter>(
 
     private suspend fun tryRestoreLogin() {
         slData?.loginToken?.let { token ->
-            try {
+            debug { "trying to restore login with a token" }
-                val ar = transport.adapter().invokeCommand(serverApi.slLoginByToken, token)
+            while( true ) {
-                slData = if (ar is AuthenticationResult.Success) {
+                try {
-                    val data: D? = ar.applicationData?.let { BossDecoder.decodeFrom(dataType, it) }
+                    val ar = transport.adapter().invokeCommand(serverApi.slLoginByToken, token)
-                    SuperloginData(ar.loginName, ar.loginToken, data)
+                    slData = if (ar is AuthenticationResult.Success) {
-                } else {
+                        val data: D? = ar.applicationData?.let { BossDecoder.decodeFrom(dataType, it) }
-                    null
+                        debug { "login restored by the token: ${ar.loginName}" }
+                        SuperloginData(ar.loginName, ar.loginToken, data)
+                    } else {
+                        debug { "failed to restore login by the token: $ar" }
+                        null
+                    }
+                    break
+                } catch (t: Throwable) {
+                    exception { "failed to restore login by token, will retry" to t }
+                    delay(1500)
                 }
-            } catch (t: Throwable) {
-                exception { "failed to restore login by token, will retry" to t }
-                delay(1500)
-                tryRestoreLogin()
             }
         } ?: warning { "tryRestoreLogin is ignored as slData is now null" }
+        adapterReady.value = true
     }
 
     init {
@@ -120,6 +140,7 @@ class SuperloginClient<D, S : WithAdapter>(
             transport.connectedFlow.collect { on ->
                 if (on) tryRestoreLogin()
                 else {
+                    adapterReady.value = false
                     _cflow.value = false
                 }
             }
@@ -131,16 +152,24 @@ class SuperloginClient<D, S : WithAdapter>(
         transport.close()
     }
 
+    /**
+     * Force dropping and re-establish underlying parsec3 connection and restore
+     * login state to the current.
+     */
     override fun reconnect() {
+        adapterReady.value = false
         transport.reconnect()
-        if (!adapterReady.isActive) {
-            adapterReady.cancel()
-            adapterReady = CompletableDeferred()
-        }
     }
 
     private var registration: Registration? = null
 
+    /**
+     * Whether the client is supposed to be logged in. Note that it is also true when
+     * there is no ready connection (means also offline), if there is information about staved
+     * loged in state. It can change at aby time as server may drop login state too. Use
+     * [state] flow to track the state changes and [adapterReady] flow to track connection state
+     * that are in fact independent to some degree.
+     */
     val isLoggedIn get() = state.value.isLoggedIn
 
     /**

src/jvmMain/kotlin/net/sergeych/superlogin/server/SuperloginServer.kt

@@ -77,7 +77,6 @@ inline fun <reified D, S : SLServerSession<D>,A: CommandHost<S>> Application.sup
  *
  *         // Sample service-specifiv api (above login api):
  *         on(api.loginName) {
- *             println("login name called. now we have $currentLoginName : $superloginData")
  *             currentLoginName
  *         }
  *     }

src/jvmTest/kotlin/net/sergeych/WsServerKtTest.kt

@@ -5,6 +5,11 @@ import io.ktor.server.engine.*
 import io.ktor.server.netty.*
 import kotlinx.coroutines.runBlocking
 import kotlinx.serialization.Serializable
+import net.sergeych.mp_logger.Log
+import net.sergeych.mp_logger.LogTag
+import net.sergeych.mp_logger.info
+import net.sergeych.mp_tools.encodeToBase64Compact
+import net.sergeych.parsec3.Adapter
 import net.sergeych.parsec3.CommandHost
 import net.sergeych.parsec3.Parsec3WSClient
 import net.sergeych.parsec3.WithAdapter
@@ -19,56 +24,66 @@ import superlogin.assertThrowsAsync
 import kotlin.random.Random
 import kotlin.test.*
 
-data class TestSession(var buzz: String = "BuZZ") : SLServerSession<TestData>() {
+class TestStorage(
-    val byLogin = mutableMapOf<String, RegistrationArgs>()
+    val byLogin: MutableMap<String, RegistrationArgs> = mutableMapOf<String, RegistrationArgs>(),
-    val byLoginId = mutableMapOf<List<Byte>, RegistrationArgs>()
+    val byLoginId: MutableMap<List<Byte>, RegistrationArgs> = mutableMapOf<List<Byte>, RegistrationArgs>(),
-    val byRestoreId = mutableMapOf<List<Byte>, RegistrationArgs>()
+    val byRestoreId: MutableMap<List<Byte>, RegistrationArgs> = mutableMapOf<List<Byte>, RegistrationArgs>(),
-    val byToken = mutableMapOf<List<Byte>, RegistrationArgs>()
+    val byToken: MutableMap<List<Byte>, RegistrationArgs> = mutableMapOf<List<Byte>, RegistrationArgs>(),
-    val tokens = mutableMapOf<String, ByteArray>()
+    val tokens: MutableMap<String, ByteArray> = mutableMapOf<String, ByteArray>(),
+)
+data class TestSession(val s: TestStorage) : SLServerSession<TestData>() {
+
+    var buzz: String = "BuZZ"
 
     override suspend fun register(ra: RegistrationArgs): AuthenticationResult {
         println("ra: ${ra.loginName} : $currentLoginName : $superloginData")
         return when {
-            ra.loginName in byLogin -> {
+            ra.loginName in s.byLogin -> {
                 AuthenticationResult.LoginUnavailable
             }
 
-            ra.loginId.toList() in byLoginId -> AuthenticationResult.LoginIdUnavailable
+            ra.loginId.toList() in s.byLoginId -> AuthenticationResult.LoginIdUnavailable
-            ra.restoreId.toList() in byRestoreId -> AuthenticationResult.RestoreIdUnavailable
+            ra.restoreId.toList() in s.byRestoreId -> AuthenticationResult.RestoreIdUnavailable
             else -> {
-                byLogin[ra.loginName] = ra
+                s.byLogin[ra.loginName] = ra
-                byRestoreId[ra.restoreId.toList()] = ra
+                s.byRestoreId[ra.restoreId.toList()] = ra
-                byLoginId[ra.loginId.toList()] = ra
+                s.byLoginId[ra.loginId.toList()] = ra
                 val token = Random.Default.nextBytes(32)
-                byToken[token.toList()] = ra
+                s.byToken[token.toList()] = ra
-                tokens[ra.loginName] = token
+                s.tokens[ra.loginName] = token
+                println("registered with token ${token.encodeToBase64Compact()}")
+                println("                      ${s.byToken[token.toList()]}")
                 AuthenticationResult.Success(ra.loginName, token, ra.extraData)
             }
         }
     }
 
     override suspend fun loginByToken(token: ByteArray): AuthenticationResult {
-        return byToken[token.toList()]?.let {
+        println("requested login by tokeb ${token.encodeToBase64Compact()}")
+        println("                         ${s.byToken[token.toList()]}")
+        println("                         ${s.byToken.size} / ${s.byLoginId.size}")
+
+        return s.byToken[token.toList()]?.let {
             AuthenticationResult.Success(it.loginName, token, it.extraData)
         }
             ?: AuthenticationResult.LoginUnavailable
     }
 
     override suspend fun requestDerivationParams(loginName: String): PasswordDerivationParams? =
-        byLogin[loginName]?.derivationParams
+        s.byLogin[loginName]?.derivationParams
 
     override suspend fun requestACOByLoginName(loginName: String, loginId: ByteArray): ByteArray? {
-        return byLogin[loginName]?.packedACO
+        return s.byLogin[loginName]?.packedACO
     }
 
     override suspend fun requestACOByRestoreId(restoreId: ByteArray): ByteArray? {
-        return byRestoreId[restoreId.toList()]?.packedACO
+        return s.byRestoreId[restoreId.toList()]?.packedACO
     }
 
     override suspend fun loginByKey(loginName: String, publicKey: PublicKey): AuthenticationResult {
-        val ra = byLogin[loginName]
+        val ra = s.byLogin[loginName]
         return if (ra != null && ra.loginPublicKey.id == publicKey.id)
-            AuthenticationResult.Success(ra.loginName, tokens[loginName]!!, ra.extraData)
+            AuthenticationResult.Success(ra.loginName, s.tokens[loginName]!!, ra.extraData)
         else AuthenticationResult.LoginUnavailable
     }
 
@@ -79,8 +94,8 @@ data class TestSession(var buzz: String = "BuZZ") : SLServerSession<TestData>()
         newLoginKey: PublicKey,
         newLoginId: ByteArray
     ) {
-        val r = byLogin[loginName]?.also {
+        val r = s.byLogin[loginName]?.also {
-           byLoginId.remove(it.loginId.toList())
+           s.byLoginId.remove(it.loginId.toList())
         }?.copy(
             packedACO = packedACO,
             derivationParams = passwordDerivationParams,
@@ -88,10 +103,10 @@ data class TestSession(var buzz: String = "BuZZ") : SLServerSession<TestData>()
             loginId = newLoginId
         )
             ?: throw RuntimeException("login not found")
-        byLogin[loginName] = r
+        s.byLogin[loginName] = r
-        byLoginId[newLoginId.toList()] = r
+        s.byLoginId[newLoginId.toList()] = r
-        byToken[currentLoginToken!!.toList()] = r
+        s.byToken[currentLoginToken!!.toList()] = r
-        byRestoreId[r.restoreId.toList()] = r
+        s.byRestoreId[r.restoreId.toList()] = r
     }
 
 }
@@ -99,6 +114,7 @@ data class TestSession(var buzz: String = "BuZZ") : SLServerSession<TestData>()
 
 class TestApiServer<T : WithAdapter> : CommandHost<T>() {
     val loginName by command<Unit, String?>()
+    val dropConnection by command<Unit,Unit>()
 }
 
 
@@ -113,9 +129,9 @@ internal class WsServerKtTest {
     @Test
     fun testWsServer() {
 
-        embeddedServer(Netty, port = 8080, module = Application::testServerModule).start(wait = false)
+        embeddedServer(Netty, port = 8085, module = Application::testServerModule).start(wait = false)
 
-        val client = Parsec3WSClient("ws://localhost:8080/api/p3")
+        val client = Parsec3WSClient("ws://localhost:8085/api/p3")
 
         runBlocking {
             val api = TestApiServer<WithAdapter>()
@@ -226,6 +242,7 @@ internal class WsServerKtTest {
         embeddedServer(Netty, port = 8082, module = Application::testServerModule).start(wait = false)
         val client = Parsec3WSClient("ws://localhost:8082/api/p3")
         runBlocking {
+            Log.connectConsole(Log.Level.DEBUG)
             val slc = SuperloginClient<TestData, WithAdapter>(client)
             val serverApi = SuperloginServerApi<WithAdapter>()
             assertThrowsAsync<SLInternalException> {
@@ -235,13 +252,42 @@ internal class WsServerKtTest {
 
     }
 
+    @Test
+    fun testDroppedConnection() {
+        embeddedServer(Netty, port = 8089, module = Application::testServerModule).start(wait = false)
+        val client = Parsec3WSClient("ws://localhost:8089/api/p3")
+        runBlocking {
+            Log.connectConsole(Log.Level.DEBUG)
+            val l = LogTag("Test")
+            val api = TestApiServer<WithAdapter>()
+            val slc = SuperloginClient<TestData, WithAdapter>(client)
+            val serverApi = SuperloginServerApi<WithAdapter>()
+
+            var rt = slc.register("foo", "passwd", TestData("bar!"))
+            assertIs<Registration.Result.Success>(rt)
+
+            assertEquals("foo", slc.call(api.loginName))
+
+            l.info { "---- breaking the connection ----------" }
+            assertThrowsAsync<Adapter.CloseError> { slc.call(api.dropConnection) }
+
+            assertTrue { slc.isLoggedIn }
+            assertEquals("foo", slc.call(api.loginName))
+        }
+
+    }
+
+
 }
 
 fun Application.testServerModule() {
-    superloginServer(TestApiServer<TestSession>(), { TestSession() }) {
+    val s = TestStorage()
+    superloginServer(TestApiServer<TestSession>(), { TestSession(s) }) {
         on(api.loginName) {
-            println("login name called. now we have $currentLoginName : $superloginData")
             currentLoginName
         }
+        on(api.dropConnection) {
+            adapter.cancel()
+        }
     }
 }