feat: Add helper methods for req-res pattern

This change adds helper methods for simplifying the request-response
pattern commonly used in models.

1 files changed, 52 insertions, 0 deletions

diff --git a/odcsim/odcsim-api/src/main/kotlin/com/atlarge/odcsim/Channels.kt b/odcsim/odcsim-api/src/main/kotlin/com/atlarge/odcsim/Channels.kt
new file mode 100644
index 00000000..b15ce3ae
--- /dev/null
+++ b/odcsim/odcsim-api/src/main/kotlin/com/atlarge/odcsim/Channels.kt
@@ -0,0 +1,52 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 atlarge-research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package com.atlarge.odcsim
+
+suspend fun <T : Any, U : Any> SendRef<T>.ask(block: (SendRef<U>) -> T): U {
+    val ctx = processContext
+    val outlet = ctx.connect(this)
+    val channel = ctx.open<U>()
+    try {
+        outlet.send(block(channel.send))
+    } finally {
+        outlet.close()
+    }
+
+    val inlet = ctx.listen(channel.receive)
+    try {
+        return inlet.receive()
+    } finally {
+        inlet.close()
+    }
+}
+
+suspend fun <T : Any> SendRef<T>.sendOnce(msg: T) {
+    val outlet = processContext.connect(this)
+    try {
+        outlet.send(msg)
+    } finally {
+        outlet.close()
+    }
+}