Express_Crud_Example/node_modules/bson/src/binary.ts
2022-01-28 22:33:42 +01:00

287 lines
8.5 KiB
TypeScript

import { Buffer } from 'buffer';
import { ensureBuffer } from './ensure_buffer';
import { uuidHexStringToBuffer } from './uuid_utils';
import { UUID, UUIDExtended } from './uuid';
import type { EJSONOptions } from './extended_json';
import { BSONError, BSONTypeError } from './error';
/** @public */
export type BinarySequence = Uint8Array | Buffer | number[];
/** @public */
export interface BinaryExtendedLegacy {
$type: string;
$binary: string;
}
/** @public */
export interface BinaryExtended {
$binary: {
subType: string;
base64: string;
};
}
/**
* A class representation of the BSON Binary type.
* @public
*/
export class Binary {
_bsontype!: 'Binary';
/**
* Binary default subtype
* @internal
*/
private static readonly BSON_BINARY_SUBTYPE_DEFAULT = 0;
/** Initial buffer default size */
static readonly BUFFER_SIZE = 256;
/** Default BSON type */
static readonly SUBTYPE_DEFAULT = 0;
/** Function BSON type */
static readonly SUBTYPE_FUNCTION = 1;
/** Byte Array BSON type */
static readonly SUBTYPE_BYTE_ARRAY = 2;
/** Deprecated UUID BSON type @deprecated Please use SUBTYPE_UUID */
static readonly SUBTYPE_UUID_OLD = 3;
/** UUID BSON type */
static readonly SUBTYPE_UUID = 4;
/** MD5 BSON type */
static readonly SUBTYPE_MD5 = 5;
/** Encrypted BSON type */
static readonly SUBTYPE_ENCRYPTED = 6;
/** Column BSON type */
static readonly SUBTYPE_COLUMN = 7;
/** User BSON type */
static readonly SUBTYPE_USER_DEFINED = 128;
buffer!: Buffer;
sub_type!: number;
position!: number;
/**
* @param buffer - a buffer object containing the binary data.
* @param subType - the option binary type.
*/
constructor(buffer?: string | BinarySequence, subType?: number) {
if (!(this instanceof Binary)) return new Binary(buffer, subType);
if (
!(buffer == null) &&
!(typeof buffer === 'string') &&
!ArrayBuffer.isView(buffer) &&
!(buffer instanceof ArrayBuffer) &&
!Array.isArray(buffer)
) {
throw new BSONTypeError(
'Binary can only be constructed from string, Buffer, TypedArray, or Array<number>'
);
}
this.sub_type = subType ?? Binary.BSON_BINARY_SUBTYPE_DEFAULT;
if (buffer == null) {
// create an empty binary buffer
this.buffer = Buffer.alloc(Binary.BUFFER_SIZE);
this.position = 0;
} else {
if (typeof buffer === 'string') {
// string
this.buffer = Buffer.from(buffer, 'binary');
} else if (Array.isArray(buffer)) {
// number[]
this.buffer = Buffer.from(buffer);
} else {
// Buffer | TypedArray | ArrayBuffer
this.buffer = ensureBuffer(buffer);
}
this.position = this.buffer.byteLength;
}
}
/**
* Updates this binary with byte_value.
*
* @param byteValue - a single byte we wish to write.
*/
put(byteValue: string | number | Uint8Array | Buffer | number[]): void {
// If it's a string and a has more than one character throw an error
if (typeof byteValue === 'string' && byteValue.length !== 1) {
throw new BSONTypeError('only accepts single character String');
} else if (typeof byteValue !== 'number' && byteValue.length !== 1)
throw new BSONTypeError('only accepts single character Uint8Array or Array');
// Decode the byte value once
let decodedByte: number;
if (typeof byteValue === 'string') {
decodedByte = byteValue.charCodeAt(0);
} else if (typeof byteValue === 'number') {
decodedByte = byteValue;
} else {
decodedByte = byteValue[0];
}
if (decodedByte < 0 || decodedByte > 255) {
throw new BSONTypeError('only accepts number in a valid unsigned byte range 0-255');
}
if (this.buffer.length > this.position) {
this.buffer[this.position++] = decodedByte;
} else {
const buffer = Buffer.alloc(Binary.BUFFER_SIZE + this.buffer.length);
// Combine the two buffers together
this.buffer.copy(buffer, 0, 0, this.buffer.length);
this.buffer = buffer;
this.buffer[this.position++] = decodedByte;
}
}
/**
* Writes a buffer or string to the binary.
*
* @param sequence - a string or buffer to be written to the Binary BSON object.
* @param offset - specify the binary of where to write the content.
*/
write(sequence: string | BinarySequence, offset: number): void {
offset = typeof offset === 'number' ? offset : this.position;
// If the buffer is to small let's extend the buffer
if (this.buffer.length < offset + sequence.length) {
const buffer = Buffer.alloc(this.buffer.length + sequence.length);
this.buffer.copy(buffer, 0, 0, this.buffer.length);
// Assign the new buffer
this.buffer = buffer;
}
if (ArrayBuffer.isView(sequence)) {
this.buffer.set(ensureBuffer(sequence), offset);
this.position =
offset + sequence.byteLength > this.position ? offset + sequence.length : this.position;
} else if (typeof sequence === 'string') {
this.buffer.write(sequence, offset, sequence.length, 'binary');
this.position =
offset + sequence.length > this.position ? offset + sequence.length : this.position;
}
}
/**
* Reads **length** bytes starting at **position**.
*
* @param position - read from the given position in the Binary.
* @param length - the number of bytes to read.
*/
read(position: number, length: number): BinarySequence {
length = length && length > 0 ? length : this.position;
// Let's return the data based on the type we have
return this.buffer.slice(position, position + length);
}
/**
* Returns the value of this binary as a string.
* @param asRaw - Will skip converting to a string
* @remarks
* This is handy when calling this function conditionally for some key value pairs and not others
*/
value(asRaw?: boolean): string | BinarySequence {
asRaw = !!asRaw;
// Optimize to serialize for the situation where the data == size of buffer
if (asRaw && this.buffer.length === this.position) {
return this.buffer;
}
// If it's a node.js buffer object
if (asRaw) {
return this.buffer.slice(0, this.position);
}
return this.buffer.toString('binary', 0, this.position);
}
/** the length of the binary sequence */
length(): number {
return this.position;
}
toJSON(): string {
return this.buffer.toString('base64');
}
toString(format?: string): string {
return this.buffer.toString(format);
}
/** @internal */
toExtendedJSON(options?: EJSONOptions): BinaryExtendedLegacy | BinaryExtended {
options = options || {};
const base64String = this.buffer.toString('base64');
const subType = Number(this.sub_type).toString(16);
if (options.legacy) {
return {
$binary: base64String,
$type: subType.length === 1 ? '0' + subType : subType
};
}
return {
$binary: {
base64: base64String,
subType: subType.length === 1 ? '0' + subType : subType
}
};
}
toUUID(): UUID {
if (this.sub_type === Binary.SUBTYPE_UUID) {
return new UUID(this.buffer.slice(0, this.position));
}
throw new BSONError(
`Binary sub_type "${this.sub_type}" is not supported for converting to UUID. Only "${Binary.SUBTYPE_UUID}" is currently supported.`
);
}
/** @internal */
static fromExtendedJSON(
doc: BinaryExtendedLegacy | BinaryExtended | UUIDExtended,
options?: EJSONOptions
): Binary {
options = options || {};
let data: Buffer | undefined;
let type;
if ('$binary' in doc) {
if (options.legacy && typeof doc.$binary === 'string' && '$type' in doc) {
type = doc.$type ? parseInt(doc.$type, 16) : 0;
data = Buffer.from(doc.$binary, 'base64');
} else {
if (typeof doc.$binary !== 'string') {
type = doc.$binary.subType ? parseInt(doc.$binary.subType, 16) : 0;
data = Buffer.from(doc.$binary.base64, 'base64');
}
}
} else if ('$uuid' in doc) {
type = 4;
data = uuidHexStringToBuffer(doc.$uuid);
}
if (!data) {
throw new BSONTypeError(`Unexpected Binary Extended JSON format ${JSON.stringify(doc)}`);
}
return new Binary(data, type);
}
/** @internal */
[Symbol.for('nodejs.util.inspect.custom')](): string {
return this.inspect();
}
inspect(): string {
const asBuffer = this.value(true);
return `new Binary(Buffer.from("${asBuffer.toString('hex')}", "hex"), ${this.sub_type})`;
}
}
Object.defineProperty(Binary.prototype, '_bsontype', { value: 'Binary' });