Package 10 — Encodings¶

Package 10 defines how component values are serialized on the wire. Four encoding methods are available, selectable via the AnyEncoding union.

AnyEncoding¶

The discriminated union over all encoding methods:

Variant	Use case
`TextEncoding`	CSV-like delimited text
`JSONEncoding`	JSON arrays/objects (new in 3.0)
`XMLEncoding`	XML elements
`BinaryEncoding`	Raw or base64 binary with explicit layout

TextEncoding¶

A CSV-like delimited text encoding. Values are converted to strings and separated by configurable delimiters.

Field	Type	Description
`base`	AbstractEncoding	Inherited id
`collapseWhiteSpaces`	bool	Collapse runs of whitespace to a single space
`decimalSeparator`	string	Character for decimal point (default `"."`)
`tokenSeparator`	string	Field delimiter within a record (required)
`blockSeparator`	string	Record delimiter (required)

Example¶

With tokenSeparator="," and blockSeparator="\n", a DataRecord with three Quantity fields encodes as:

23.5,1013.25,65.0
24.1,1012.80,63.5

JSONEncoding¶

JSON-based encoding, new in SWE Common 3.0. Gives you a choice between object-style (field names as keys) and array-style (positional values) encoding.

Field	Type	Description
`base`	AbstractEncoding	Inherited id
`recordsAsArrays`	bool	Encode DataRecord fields as JSON arrays (default false)
`vectorsAsArrays`	bool	Encode Vector coordinates as JSON arrays (default false)

When recordsAsArrays is false (the default), a DataRecord serializes as:

{"temperature": 23.5, "humidity": 65.0, "timestamp": "2025-06-15T14:30:00Z"}

When true, the same record becomes:

[23.5, 65.0, "2025-06-15T14:30:00Z"]

XMLEncoding¶

XML element-based encoding.

Field	Type	Description
`base`	AbstractEncoding	Inherited id
`namespace`	string	XML namespace URI

BinaryEncoding¶

Raw or base64 binary encoding with explicit member layout. This is the most compact encoding and gives you full control over byte order, data types, and padding.

Field	Type	Description
`base`	AbstractEncoding	Inherited id
`byteOrder`	ByteOrder	`bigEndian` or `littleEndian` (required)
`byteEncoding`	ByteEncoding	`raw` or `base64` (required)
`byteLength`	uint64	Total stream length if known
`members`	list of BinaryMember	Layout of each member (required, min 1)

BinaryMember¶

Each member in the binary layout is either a BinaryComponent (single scalar) or a BinaryBlock (group of values with possible compression/encryption).

BinaryComponent — parameters for a single scalar value:

Field	Type	Description
`base`	AbstractSWE	Inherited id
`encryption`	string	URI — encryption method
`significantBits`	uint32	Number of significant bits
`bitLength`	uint32	Bit length on wire
`byteLength`	uint32	Byte length on wire
`dataType`	string	URI — data type (required)
`ref`	string	Path reference to the component (required)

BinaryBlock — parameters for a block of values:

Field	Type	Description
`base`	AbstractSWE	Inherited id
`compression`	string	URI — compression method
`encryption`	string	URI — encryption method
`paddingBytesBefore`	uint32	Leading padding
`paddingBytesAfter`	uint32	Trailing padding
`byteLength`	uint32	Block size on wire
`ref`	string	Path reference (required)

ByteOrder and ByteEncoding¶

Cap'n ProtoFlatBuffersProtocol Buffers

enum ByteOrder    { bigEndian @0; littleEndian @1; }
enum ByteEncoding { raw @0; base64 @1; }

enum ByteOrder : byte    { BigEndian = 0, LittleEndian }
enum ByteEncoding : byte { Raw = 0, Base64 }

enum ByteOrder {
  BYTE_ORDER_UNSPECIFIED = 0;
  BYTE_ORDER_BIG_ENDIAN = 1;
  BYTE_ORDER_LITTLE_ENDIAN = 2;
}
enum ByteEncoding {
  BYTE_ENCODING_UNSPECIFIED = 0;
  BYTE_ENCODING_RAW = 1;
  BYTE_ENCODING_BASE64 = 2;
}

Choosing an encoding¶

Encoding	Best for
TextEncoding	Human-readable output, CSV interoperability, debugging
JSONEncoding	Web APIs, JavaScript consumers, REST services
XMLEncoding	OGC XML ecosystem interoperability
BinaryEncoding	High-throughput sensor streams, embedded systems, minimal bandwidth