TLV Variables

ndn.encoding.tlv_type.BinaryStr

A binary string is any of bytes, bytearray, memoryview.

alias of bytes | bytearray | memoryview

ndn.encoding.tlv_type.FormalName

A FormalName is a list of encoded Components.

alias of List[bytes | bytearray | memoryview]

ndn.encoding.tlv_type.NonStrictName

A NonStrictName is any of below:

  • A URI string.

  • A list or iterator of Components, in the form of either encoded TLV or URI string.

  • An encoded Name of type bytes, bytearray or memoryview.

See also FormalName and NonStrictName

alias of Iterable[bytes | bytearray | memoryview | str] | str | bytes | bytearray | memoryview

ndn.encoding.tlv_type.VarBinaryStr

A variant binary string is a bytearray or a non-readonly memoryview.

alias of bytearray | memoryview

ndn.encoding.tlv_type.is_binary_str(var)

Check whether var is of type BinaryStr.

Parameters:

var – The variable to check.

Returns:

True if var is a BinaryStr.

ndn.encoding.tlv_var.get_tl_num_size(val)

Calculate the length of a TL variable.

Parameters:

val (int) – an integer standing for Type or Length.

Return type:

int

Returns:

The length of var.

ndn.encoding.tlv_var.pack_uint_bytes(val)

Pack an non-negative integer value into bytes

Parameters:

val (int) – the integer.

Return type:

bytes

Returns:

the buffer.

ndn.encoding.tlv_var.parse_and_check_tl(wire, expected_type)

Parse Type and Length, and then check:

  • If the Type equals expected_type;

  • If the Length equals the length of wire.

Parameters:

  • wire (Union[bytes, bytearray, memoryview]) – the TLV encoded wire.

  • expected_type (int) – expected Type.

Return type:

memoryview

Returns:

a pointer to the memory of Value.

ndn.encoding.tlv_var.parse_tl_num(buf, offset=0)

Parse a Type or Length variable from a buffer.

Parameters:

  • buf (Union[bytes, bytearray, memoryview]) – the buffer.

  • offset (int) – the starting offset.

Return type:

(int, int)

Returns:

a pair (value, size parsed).

async ndn.encoding.tlv_var.read_tl_num_from_stream(reader, bio)

Read a Type or Length variable from a StreamReader.

Parameters:

  • reader (StreamReader) – the StreamReader.

  • bio (BytesIO) – the BytesIO to write whatever is read from the stream.

Return type:

int

Returns:

the value read.

ndn.encoding.tlv_var.write_tl_num(val, buf, offset=0)

Write a Type or Length value into a buffer.

Parameters:

  • val (int) – the value.

  • buf (Union[bytearray, memoryview]) – the buffer.

  • offset (int) – the starting offset.

Return type:

int

Returns:

the encoded length.