DataChannel: decoding / encoding

tests/testdatachannel.nim

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+import ../webrtc/datachannel
+import chronos/unittest2/asynctests
+import binary_serialization
+
+suite "DataChannel encoding":
+  test "DataChannelOpenMessage":
+    let msg = @[
+        0x03'u8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+        0x03, 0x00, 0x03, 0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72]
+    check msg == Binary.encode(Binary.decode(msg, DataChannelMessage))
+    check Binary.decode(msg, DataChannelMessage).openMessage ==
+        DataChannelOpenMessage(
+          channelType: Reliable,
+          priority: 0,
+          reliabilityParameter: 0,
+          labelLength: 3,
+          protocolLength: 3,
+          label: @[102, 111, 111],
+          protocol: @[98, 97, 114]
+        )
+
+  test "DataChannelAck":
+    let msg = @[0x02'u8]
+    check msg == Binary.encode(Binary.decode(msg, DataChannelMessage))
+    check Binary.decode(msg, DataChannelMessage).messageType == Ack

webrtc/datachannel.nim

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+# Nim-WebRTC
+# Copyright (c) 2023 Status Research & Development GmbH
+# Licensed under either of
+#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
+#  * MIT license ([LICENSE-MIT](LICENSE-MIT))
+# at your option.
+# This file may not be copied, modified, or distributed except according to
+# those terms.
+
+import chronos,
+       chronicles,
+       binary_serialization
+
+export binary_serialization
+
+logScope:
+  topics = "webrtc datachannel"
+
+type
+  DataChannelMessageType* {.size: 1.} = enum
+    Reserved = 0x00
+    Ack = 0x02
+    Open = 0x03
+
+  DataChannelMessage* = object
+    case messageType*: DataChannelMessageType
+    of Open: openMessage*: DataChannelOpenMessage
+    else: discard
+
+  DataChannelType {.size: 1.} = enum
+    Reliable = 0x00
+    PartialReliableRexmit = 0x01
+    PartialReliableTimed = 0x02
+    ReliableUnordered = 0x80
+    PartialReliableRexmitUnordered = 0x81
+    PartialReliableTimedUnorderd = 0x82
+
+
+  DataChannelOpenMessage* = object
+    channelType*: DataChannelType
+    priority*: uint16
+    reliabilityParameter*: uint32
+    labelLength* {.bin_value: it.label.len.}: uint16
+    protocolLength* {.bin_value: it.protocol.len.}: uint16
+    label* {.bin_len: it.labelLength.}: seq[byte]
+    protocol* {.bin_len: it.protocolLength.}: seq[byte]