1 files changed, 92 insertions, 0 deletions
diff --git a/hv-collector-core/src/main/kotlin/org/onap/dcae/collectors/veshv/impl/wire/WireFrameSink.kt b/hv-collector-core/src/main/kotlin/org/onap/dcae/collectors/veshv/impl/wire/WireFrameSink.kt
new file mode 100644
index 00000000..bc9c8389
--- /dev/null
+++ b/hv-collector-core/src/main/kotlin/org/onap/dcae/collectors/veshv/impl/wire/WireFrameSink.kt
@@ -0,0 +1,92 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.impl.wire
+
+import io.netty.buffer.ByteBuf
+import org.onap.dcae.collectors.veshv.domain.WireFrame
+import org.onap.dcae.collectors.veshv.domain.exceptions.MissingWireFrameBytesException
+import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import reactor.core.publisher.FluxSink
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since May 2018
+ */
+internal class WireFrameSink(
+        private val streamBuffer: ByteBuf,
+        private val sink: FluxSink<WireFrame>,
+        private val requestedFrameCount: Long) {
+
+    fun handleSubscriber() {
+        logger.trace { "Decoder buffer capacity before decoding frame: ${streamBuffer.capacity()}" }
+
+        try {
+            if (requestedFrameCount == Long.MAX_VALUE) {
+                logger.trace { "Push based strategy" }
+                pushAvailableFrames()
+            } else {
+                logger.trace { "Pull based strategy - req $requestedFrameCount" }
+                pushUpToNumberOfFrames()
+            }
+        } catch (ex: Exception) {
+            sink.error(ex)
+        }
+
+        logger.trace { "Decoder buffer capacity after decoding frame: ${streamBuffer.capacity()}" }
+
+    }
+
+    private fun pushAvailableFrames() {
+        var nextFrame = decodeFirstFrameFromBuffer()
+        while (nextFrame != null && !sink.isCancelled) {
+            sink.next(nextFrame)
+            nextFrame = decodeFirstFrameFromBuffer()
+        }
+        sink.complete()
+    }
+
+    private fun pushUpToNumberOfFrames() {
+        var nextFrame = decodeFirstFrameFromBuffer()
+        var remaining = requestedFrameCount
+        loop@ while (nextFrame != null && !sink.isCancelled) {
+            sink.next(nextFrame)
+            if (--remaining > 0) {
+                nextFrame = decodeFirstFrameFromBuffer()
+            } else {
+                break@loop
+            }
+        }
+        if (remaining > 0 && nextFrame == null) {
+            sink.complete()
+        }
+    }
+
+    private fun decodeFirstFrameFromBuffer(): WireFrame? =
+            try {
+                WireFrame.decodeFirst(streamBuffer)
+            } catch (ex: MissingWireFrameBytesException) {
+                logger.debug { "${ex.message} - waiting for more data" }
+                null
+            }
+
+    companion object {
+        private val logger = Logger(WireFrameSink::class)
+    }
+}