Clean up property access syntax

controls-core/src/commonMain/kotlin/space/kscience/controls/api/Device.kt

@@ -39,7 +39,7 @@ public interface Device : AutoCloseable, ContextAware, CoroutineScope {
     public val actionDescriptors: Collection<ActionDescriptor>
 
     /**
-     * Read physical state of property and update/push notifications if needed.
+     * Read the physical state of property and update/push notifications if needed.
      */
     public suspend fun readProperty(propertyName: String): Meta
 
@@ -71,7 +71,7 @@ public interface Device : AutoCloseable, ContextAware, CoroutineScope {
      * Send an action request and suspend caller while request is being processed.
      * Could return null if request does not return a meaningful answer.
      */
-    public suspend fun execute(action: String, argument: Meta? = null): Meta?
+    public suspend fun execute(actionName: String, argument: Meta? = null): Meta?
 
     /**
      * Initialize the device. This function suspends until the device is finished initialization

controls-core/src/commonMain/kotlin/space/kscience/controls/spec/DeviceBase.kt

@@ -13,10 +13,29 @@ import space.kscience.dataforge.meta.Meta
 import kotlin.coroutines.CoroutineContext
 
 
+@OptIn(InternalDeviceAPI::class)
+private suspend fun <D : Device, T> WritableDevicePropertySpec<D, T>.writeMeta(device: D, item: Meta) {
+    write(device, converter.metaToObject(item) ?: error("Meta $item could not be read with $converter"))
+}
+
+@OptIn(InternalDeviceAPI::class)
+private suspend fun <D : Device, T> DevicePropertySpec<D, T>.readMeta(device: D): Meta? =
+    read(device)?.let(converter::objectToMeta)
+
+
+private suspend fun <D : Device, I, O> DeviceActionSpec<D, I, O>.executeWithMeta(
+    device: D,
+    item: Meta?,
+): Meta? {
+    val arg = item?.let { inputConverter.metaToObject(item) }
+    val res = execute(device, arg)
+    return res?.let { outputConverter.objectToMeta(res) }
+}
+
+
 /**
  * A base abstractions for [Device], introducing specifications for properties
  */
-@OptIn(InternalDeviceAPI::class)
 public abstract class DeviceBase<D : Device>(
     override val context: Context = Global,
     override val meta: Meta = Meta.EMPTY,
@@ -83,10 +102,17 @@ public abstract class DeviceBase<D : Device>(
      * The logical state is updated after read
      */
     override suspend fun readProperty(propertyName: String): Meta {
-        val newValue = properties[propertyName]?.readMeta(self)
+        val spec = properties[propertyName] ?: error("Property with name $propertyName not found")
-            ?: error("A property with name $propertyName is not registered in $this")
+        val meta = spec.readMeta(self) ?: error("Failed to read property $propertyName")
-        updateLogical(propertyName, newValue)
+        updateLogical(propertyName, meta)
-        return newValue
+        return meta
+    }
+
+    public suspend fun readPropertyOrNull(propertyName: String): Meta? {
+        val spec = properties[propertyName] ?: return null
+        val meta = spec.readMeta(self) ?: return null
+        updateLogical(propertyName, meta)
+        return meta
     }
 
     override fun getProperty(propertyName: String): Meta? = logicalState[propertyName]
@@ -98,40 +124,27 @@ public abstract class DeviceBase<D : Device>(
     }
 
     override suspend fun writeProperty(propertyName: String, value: Meta): Unit {
-        //If there is a physical property with a given name, invalidate logical property and write physical one
+        when (val property = properties[propertyName]) {
-        (properties[propertyName] as? WritableDevicePropertySpec<D, out Any?>)?.let {
+            null -> {
-            invalidate(propertyName)
+                //If there is a physical property with a given name, invalidate logical property and write physical one
-            it.writeMeta(self, value)
+                updateLogical(propertyName, value)
-        } ?: run {
+            }
-            updateLogical(propertyName, value)
+
+            is WritableDevicePropertySpec -> {
+                invalidate(propertyName)
+                property.writeMeta(self, value)
+            }
+
+            else -> {
+                error("Property $property is not writeable")
+            }
         }
     }
 
-    override suspend fun execute(action: String, argument: Meta?): Meta? =
+    override suspend fun execute(actionName: String, argument: Meta?): Meta? {
-        actions[action]?.executeWithMeta(self, argument)
+        val spec = actions[actionName] ?: error("Action with name $actionName not found")
+        return spec.executeWithMeta(self, argument)
+    }
 
 }
 
-/**
- * A device generated from specification
- * @param D recursive self-type for properties and actions
- */
-public open class DeviceBySpec<D : Device>(
-    public val spec: DeviceSpec<in D>,
-    context: Context = Global,
-    meta: Meta = Meta.EMPTY,
-) : DeviceBase<D>(context, meta) {
-    override val properties: Map<String, DevicePropertySpec<D, *>> get() = spec.properties
-    override val actions: Map<String, DeviceActionSpec<D, *, *>> get() = spec.actions
-
-    override suspend fun open(): Unit = with(spec) {
-        super.open()
-        self.onOpen()
-    }
-
-    override fun close(): Unit = with(spec) {
-        self.onClose()
-        super.close()
-    }
-}
-

controls-core/src/commonMain/kotlin/space/kscience/controls/spec/DeviceBySpec.kt

@@ -0,0 +1,29 @@
+package space.kscience.controls.spec
+
+import space.kscience.controls.api.Device
+import space.kscience.dataforge.context.Context
+import space.kscience.dataforge.context.Global
+import space.kscience.dataforge.meta.Meta
+
+/**
+ * A device generated from specification
+ * @param D recursive self-type for properties and actions
+ */
+public open class DeviceBySpec<D : Device>(
+    public val spec: DeviceSpec<in D>,
+    context: Context = Global,
+    meta: Meta = Meta.EMPTY,
+) : DeviceBase<D>(context, meta) {
+    override val properties: Map<String, DevicePropertySpec<D, *>> get() = spec.properties
+    override val actions: Map<String, DeviceActionSpec<D, *, *>> get() = spec.actions
+
+    override suspend fun open(): Unit = with(spec) {
+        super.open()
+        self.onOpen()
+    }
+
+    override fun close(): Unit = with(spec) {
+        self.onClose()
+        super.close()
+    }
+}

controls-core/src/commonMain/kotlin/space/kscience/controls/spec/DevicePropertySpec.kt

@@ -10,7 +10,6 @@ import space.kscience.controls.api.ActionDescriptor
 import space.kscience.controls.api.Device
 import space.kscience.controls.api.PropertyChangedMessage
 import space.kscience.controls.api.PropertyDescriptor
-import space.kscience.dataforge.meta.Meta
 import space.kscience.dataforge.meta.transformations.MetaConverter
 
 
@@ -36,17 +35,14 @@ public interface DevicePropertySpec<in D : Device, T> {
      */
     @InternalDeviceAPI
     public suspend fun read(device: D): T?
+
 }
 
 /**
- * Property name, should be unique in device
+ * Property name should be unique in a device
  */
 public val DevicePropertySpec<*, *>.name: String get() = descriptor.name
 
-@OptIn(InternalDeviceAPI::class)
-public suspend fun <D : Device, T> DevicePropertySpec<D, T>.readMeta(device: D): Meta? =
-    read(device)?.let(converter::objectToMeta)
-
 
 public interface WritableDevicePropertySpec<in D : Device, T> : DevicePropertySpec<D, T> {
     /**
@@ -54,11 +50,7 @@ public interface WritableDevicePropertySpec<in D : Device, T> : DevicePropertySp
      */
     @InternalDeviceAPI
     public suspend fun write(device: D, value: T)
-}
 
-@OptIn(InternalDeviceAPI::class)
-public suspend fun <D : Device, T> WritableDevicePropertySpec<D, T>.writeMeta(device: D, item: Meta) {
-    write(device, converter.metaToObject(item) ?: error("Meta $item could not be read with $converter"))
 }
 
 public interface DeviceActionSpec<in D : Device, I, O> {
@@ -82,29 +74,16 @@ public interface DeviceActionSpec<in D : Device, I, O> {
  */
 public val DeviceActionSpec<*, *, *>.name: String get() = descriptor.name
 
-public suspend fun <D : Device, I, O> DeviceActionSpec<D, I, O>.executeWithMeta(
+public suspend fun <T, D : Device> D.read(propertySpec: DevicePropertySpec<D, T>): T =
-    device: D,
+    propertySpec.converter.metaToObject(readProperty(propertySpec.name)) ?: error("Can't convert result from meta")
-    item: Meta?,
-): Meta? {
-    val arg = item?.let { inputConverter.metaToObject(item) }
-    val res = execute(device, arg)
-    return res?.let { outputConverter.objectToMeta(res) }
-}
 
 /**
  * Read typed value and update/push event if needed.
  * Return null if property read is not successful or property is undefined.
  */
-@OptIn(InternalDeviceAPI::class)
+public suspend fun <T, D : DeviceBase<D>> D.readOrNull(propertySpec: DevicePropertySpec<D, T>): T? =
-public suspend fun <T, D : Device> D.readOrNull(propertySpec: DevicePropertySpec<D, T>): T? {
+    readPropertyOrNull(propertySpec.name)?.let(propertySpec.converter::metaToObject)
-    val res = propertySpec.read(this) ?: return null
-    @Suppress("UNCHECKED_CAST")
-    (this as? DeviceBase<D>)?.updateLogical(propertySpec, res)
-    return res
-}
 
-public suspend fun <T, D : Device> D.read(propertySpec: DevicePropertySpec<D, T>): T =
-    readOrNull(propertySpec) ?: error("Failed to read property ${propertySpec.name} state")
 
 public operator fun <T, D : Device> D.get(propertySpec: DevicePropertySpec<D, T>): T? =
     getProperty(propertySpec.name)?.let(propertySpec.converter::metaToObject)
@@ -112,34 +91,17 @@ public operator fun <T, D : Device> D.get(propertySpec: DevicePropertySpec<D, T>
 /**
  * Write typed property state and invalidate logical state
  */
-@OptIn(InternalDeviceAPI::class)
 public suspend fun <T, D : Device> D.write(propertySpec: WritableDevicePropertySpec<D, T>, value: T) {
-    invalidate(propertySpec.name)
+    writeProperty(propertySpec.name, propertySpec.converter.objectToMeta(value))
-    propertySpec.write(this, value)
-    //perform asynchronous read and update after write
-    launch {
-        read(propertySpec)
-    }
 }
 
 /**
  * Fire and forget variant of property writing. Actual write is performed asynchronously on a [Device] scope
  */
-public operator fun <T, D : Device> D.set(propertySpec: WritableDevicePropertySpec<D, T>, value: T): Unit {
+public operator fun <T, D : Device> D.set(propertySpec: WritableDevicePropertySpec<D, T>, value: T): Job = launch {
-    launch {
+    write(propertySpec, value)
-        write(propertySpec, value)
-    }
 }
 
-/**
- * Reset the logical state of a property
- */
-public suspend fun <D : Device> D.invalidate(propertySpec: DevicePropertySpec<D, *>) {
-    invalidate(propertySpec.name)
-}
-
-public suspend fun <I, O, D : Device> D.execute(actionSpec: DeviceActionSpec<D, I, O>, input: I? = null): O? =
-    actionSpec.execute(this, input)
 
 /**
  * A type safe property change listener
@@ -152,4 +114,14 @@ public fun <D : Device, T> Device.onPropertyChange(
     .filter { it.property == spec.name }
     .onEach { change ->
         change.callback(spec.converter.metaToObject(change.value))
-    }.launchIn(this)
+    }.launchIn(this)
+
+/**
+ * Reset the logical state of a property
+ */
+public suspend fun <D : Device> D.invalidate(propertySpec: DevicePropertySpec<D, *>) {
+    invalidate(propertySpec.name)
+}
+
+public suspend fun <I, O, D : Device> D.execute(actionSpec: DeviceActionSpec<D, I, O>, input: I? = null): O? =
+    actionSpec.execute(this, input)

controls-core/src/commonMain/kotlin/space/kscience/controls/spec/deviceExtensions.kt

@@ -9,7 +9,7 @@ import kotlin.time.Duration
 
 /**
  * Perform a recurring asynchronous read action and return a flow of results.
- * The flow is lazy so action is not performed unless flow is consumed.
+ * The flow is lazy, so action is not performed unless flow is consumed.
  * The flow uses called context. In order to call it on device context, use `flowOn(coroutineContext)`.
  *
  * The flow is canceled when the device scope is canceled

controls-opcua/src/test/kotlin/space/kscience/controls/opcua/client/OpcUaClientTest.kt

@@ -28,8 +28,6 @@ class OpcUaClientTest {
                 return DemoOpcUaDevice(config)
             }
 
-            inline fun <R> use(block: (DemoOpcUaDevice) -> R): R = build().use(block)
-
             val randomDouble by doubleProperty(read = DemoOpcUaDevice::readRandomDouble)
 
         }
@@ -40,7 +38,7 @@ class OpcUaClientTest {
     @OptIn(ExperimentalCoroutinesApi::class)
     @Test
     fun testReadDouble() = runTest {
-        DemoOpcUaDevice.use{
+        DemoOpcUaDevice.build().use{
             println(it.read(DemoOpcUaDevice.randomDouble))
         }
     }