/// <summary>
/// Try to create an <see cref="CoapOption"/> from the option number and data.
/// </summary>
/// <param name="number"></param>
/// <param name="data"></param>
/// <returns><value>null</value> if the option is unsupported.</returns>
/// <exception cref="CoapOptionException">If the option number is unsuppported and is critical (See RFC 7252 Section 5.4.1)</exception>
public CoapOption Create(int number, byte[] data = null)
{
CoapOption option;
// Let the exception get thrown if index is out of range
if (_options.TryGetValue(number, out var type))
{
option = (CoapOption)Activator.CreateInstance(type);
}
else
{
// Critial option must be registered as they're esssential for understanding the message
if (number % 2 == 1)
{
throw new CoapOptionException($"Unsupported critical option ({number})", new ArgumentOutOfRangeException(nameof(number)));
}
// Return a placeholder option to give the application chance at reading them
option = new CoapOption(number, type: OptionType.Opaque);
}
if (data != null)
{
option.FromBytes(data);
}
return(option);
}
public void TestOpaqueOption(byte[] data, int length)
{
var option = new CoapOption(0, type: OptionType.Opaque, maxLength: 256);
option.ValueOpaque = new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 };
Assert.AreEqual(8, option.Length);
Assert.AreEqual(new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 }, option.ValueOpaque);
Assert.AreEqual(new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 }, option.GetBytes());
}
public static string Convert(CoapOption option)
{
if (option is null)
{
return(string.Empty);
}
var name = Consts.CoapOptionTypes.SingleOrDefault(p => p.Item2 == option.GetType()).Item1
?? option.GetType().Name;
return(name);
}
public void TestOpaqueOption()
{
var option = new CoapOption(0, type: OptionType.Opaque);
option.ValueOpaque = new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 };
Assert.AreEqual(8, option.Length);
Assert.AreEqual(new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 }, option.ValueOpaque);
Assert.AreEqual(new byte[] { 0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xF0 }, option.GetBytes());
option.FromBytes(new byte[] { 0xAA, 0x55, 0x11 });
Assert.AreEqual(3, option.Length);
Assert.AreEqual(new byte[] { 0xAA, 0x55, 0x11 }, option.ValueOpaque);
}
public void TestValueOption(uint value, int length, byte[] expected)
{
var optionToBytes = new CoapOption(0, type: OptionType.UInt, maxLength: 4);
optionToBytes.ValueUInt = value;
Assert.AreEqual(length, optionToBytes.Length);
Assert.AreEqual(expected, optionToBytes.GetBytes());
var optionFromBytes = new CoapOption(0, type: OptionType.UInt, maxLength: 4);
optionFromBytes.FromBytes(expected);
Assert.AreEqual(length, optionFromBytes.Length);
Assert.AreEqual(value, optionFromBytes.ValueUInt);
}
public IEnumerable <CoapOption> DeserializeOptions(EndianBinaryReader reader)
{
var options = new List <CoapOption>();
var nextOptionNumber = 0;
while (!reader.EndOfStream())
{
var smallDeltaLength = reader.ReadByte();
if (smallDeltaLength == 0xFF)
{
break;
}
var delta = (smallDeltaLength >> 4) & 0xF;
var length = smallDeltaLength & 0xF;
// Read extended delta
if (delta == 13)
{
var int8Delta = reader.ReadByte();
delta = int8Delta + 13;
}
else if (delta == 14)
{
var int16Delta = reader.ReadUInt16();
delta = int16Delta + 269;
}
// Read extended length
if (length == 13)
{
var int8Length = reader.ReadByte();
length = int8Length + 13;
}
else if (length == 14)
{
var int16Length = reader.ReadUInt16();
length = int16Length + 269;
}
var number = delta + nextOptionNumber;
var value = reader.ReadBytes(length);
options.Add(CoapOption.FromNumberValue(number, value));
nextOptionNumber = number;
}
return(options);
}
public byte[] TestMessageEncodeOptions(CoapOption option)
{
_message.OptionFactory = new Options.OptionFactory();
_message.OptionFactory.Register <TestOpaqueCoapOption>();
_message.Code = CoapMessageCode.Get;
_message.Type = CoapMessageType.Confirmable;
_message.Id = 0;
_message.Options.Add(option);
using (var writer = new MemoryStream())
{
_message.Encode(writer);
return(writer.ToArray());
}
}
public void TestOptionInvalidCastException()
{
var option = new CoapOption(0);
Assert.Throws <InvalidCastException>(() => _ = option.ValueString);
Assert.Throws <InvalidCastException>(() => _ = option.ValueString = "test");
Assert.Throws <InvalidCastException>(() => _ = option.ValueOpaque);
Assert.Throws <InvalidCastException>(() => _ = option.ValueOpaque = Encoding.UTF8.GetBytes("test"));
Assert.Throws <InvalidCastException>(() => _ = option.ValueUInt);
Assert.Throws <InvalidCastException>(() => _ = option.ValueUInt = 1234);
Assert.Throws <InvalidCastException>(() => _ = option.DefaultString);
Assert.Throws <InvalidCastException>(() => _ = option.DefaultOpaque);
Assert.Throws <InvalidCastException>(() => _ = option.DefaultUInt);
option.FromBytes(null); // No-op
option.FromBytes(new byte[] {}); // No-op
Assert.Throws <InvalidCastException>(() => option.FromBytes(new byte[] { 0x12 }));
}
public void NullOptionComapreNull(CoapOption option)
{
Assert.True(option.Equals(option));
}