7fife-backend/node_modules/mongodb/lib/cmap/wire_protocol/compression.js

81 lines
3.0 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.decompress = exports.compress = exports.uncompressibleCommands = exports.Compressor = void 0;
const util_1 = require("util");
const zlib = require("zlib");
const constants_1 = require("../../constants");
const deps_1 = require("../../deps");
const error_1 = require("../../error");
/** @public */
exports.Compressor = Object.freeze({
none: 0,
snappy: 1,
zlib: 2,
zstd: 3
});
exports.uncompressibleCommands = new Set([
constants_1.LEGACY_HELLO_COMMAND,
'saslStart',
'saslContinue',
'getnonce',
'authenticate',
'createUser',
'updateUser',
'copydbSaslStart',
'copydbgetnonce',
'copydb'
]);
const ZSTD_COMPRESSION_LEVEL = 3;
const zlibInflate = (0, util_1.promisify)(zlib.inflate.bind(zlib));
const zlibDeflate = (0, util_1.promisify)(zlib.deflate.bind(zlib));
// Facilitate compressing a message using an agreed compressor
async function compress(options, dataToBeCompressed) {
const zlibOptions = {};
switch (options.agreedCompressor) {
case 'snappy':
if ('kModuleError' in deps_1.Snappy) {
throw deps_1.Snappy['kModuleError'];
}
return deps_1.Snappy.compress(dataToBeCompressed);
case 'zstd':
if ('kModuleError' in deps_1.ZStandard) {
throw deps_1.ZStandard['kModuleError'];
}
return deps_1.ZStandard.compress(dataToBeCompressed, ZSTD_COMPRESSION_LEVEL);
case 'zlib':
if (options.zlibCompressionLevel) {
zlibOptions.level = options.zlibCompressionLevel;
}
return zlibDeflate(dataToBeCompressed, zlibOptions);
default:
throw new error_1.MongoInvalidArgumentError(`Unknown compressor ${options.agreedCompressor} failed to compress`);
}
}
exports.compress = compress;
// Decompress a message using the given compressor
async function decompress(compressorID, compressedData) {
if (compressorID !== exports.Compressor.snappy &&
compressorID !== exports.Compressor.zstd &&
compressorID !== exports.Compressor.zlib &&
compressorID !== exports.Compressor.none) {
throw new error_1.MongoDecompressionError(`Server sent message compressed using an unsupported compressor. (Received compressor ID ${compressorID})`);
}
switch (compressorID) {
case exports.Compressor.snappy:
if ('kModuleError' in deps_1.Snappy) {
throw deps_1.Snappy['kModuleError'];
}
return deps_1.Snappy.uncompress(compressedData, { asBuffer: true });
case exports.Compressor.zstd:
if ('kModuleError' in deps_1.ZStandard) {
throw deps_1.ZStandard['kModuleError'];
}
return deps_1.ZStandard.decompress(compressedData);
case exports.Compressor.zlib:
return zlibInflate(compressedData);
default:
return compressedData;
}
}
exports.decompress = decompress;
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