API Reference

Core Classes

`KLVParser`

Low-level iterator for raw KLV triplets.

class KLVParser implements Iterator<KLVPair>, Iterable<KLVPair> {
  constructor(source: Uint8Array, options: { keyLength: number });
  next(): IteratorResult<KLVPair>;
  [Symbol.iterator](): Iterator<KLVPair>;
}

Options:

keyLength (default: 16) — number of bytes forming the key

`StreamParser`

High-level parser that dispatches 16-byte Universal Labels to registered set parsers.

class StreamParser implements Iterable<Element> {
  static readonly parsers: Map<string, SetParserCtor>;
  static register(ctor: SetParserCtor & { key: Bytes }): void;
  constructor(source: Uint8Array);
  [Symbol.iterator](): Iterator<Element>;
}

`SetParser`

Base class for nested KLV local sets.

abstract class SetParser extends Element {
  readonly items: Map<string, Element>;
  get(key: Bytes | string): Element | undefined;
  toBytes(): Uint8Array;
  toString(): string;
  static registerParser(setClass, parserCtor): void;
}

`Element`

Abstract base for all KLV elements.

abstract class Element {
  readonly key: Uint8Array;
  value: unknown;
  get name(): string;
  get length(): Uint8Array;  // BER-encoded
  abstract toValueBytes(): Uint8Array;
  toBytes(): Uint8Array;
  toString(): string;
}

`UnknownElement`

Fallback element for unrecognized keys.

class UnknownElement extends Element {
  constructor(key: Uint8Array, value: Uint8Array);
  toValueBytes(): Uint8Array;
}

Element Parser Classes

`BytesElementParser`

Raw bytes. value is a BytesValue with:

value.value: Uint8Array — raw bytes
value.toString() → "0xAA43" style hex string

`StringElementParser`

UTF-8 strings. value is a StringValue with:

value.value: string — decoded string
Accepts Uint8Array (decoded) or string (stored directly)

`DateTimeElementParser`

Microsecond timestamps. value is a DateTimeValue with:

value.value: Date — JavaScript Date (ms precision)
value.toString() → "2009-01-12 22:08:22+00:00"
Lossless re-encoding via BigInt

`MappedElementParser`

Linear-mapped fixed-point floats. value is a MappedValue with:

value.value: number | null — decoded float, null if error sentinel
value.toString() → "159.97436484321355" or "147.0" for whole numbers
Subclasses must declare static _domain, static _range, static _errorVal

Utility Functions

BER

berEncode(value: number): Uint8Array
berDecode(value: Uint8Array): number

Checksum

packetChecksum(data: Uint8Array): Uint8Array  // 2 bytes

Float Conversion

linearMap(srcValue, srcDomain, dstRange): number
bytesToFloat(value, domain, range, errorVal?): number | null
floatToBytes(value, domain, range, errorVal?): Uint8Array

Integer

bytesToInt(value: Uint8Array, signed?: boolean): number
intToBytes(value: number, length?: number, signed?: boolean): Uint8Array

DateTime

bytesToDatetime(value: Uint8Array): Date
datetimeToBytes(value: Date): Uint8Array

String

bytesToStr(value: Uint8Array): string
strToBytes(value: string): Uint8Array

Hex String

bytesToHexstr(value: Uint8Array, start?, sep?): string
hexstrToBytes(value: string): Uint8Array

Error Classes

Class	Extends	When thrown
`KLVError`	`Error`	Base for all library errors
`BERDecodeError`	`KLVError`	Malformed BER length field
`RangeError`	`KLVError`	Value outside linear map domain/range
`TruncatedDataError`	`KLVError`	Buffer ends unexpectedly mid-field
`LengthError`	`KLVError`	Wrong byte count for data type
`ValidationError`	`KLVError`	Schema validation failure

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