62 lines
3.0 KiB
JavaScript
62 lines
3.0 KiB
JavaScript
|
"use strict";
|
||
|
Object.defineProperty(exports, "__esModule", { value: true });
|
||
|
exports.encodeIntoCompressedBase64 = exports.decodeFromCompressedBase64 = exports.decompress = void 0;
|
||
|
/*
|
||
|
* This is a TypeScript port of the original Java version, which was written by
|
||
|
* Gil Tene as described in
|
||
|
* https://github.com/HdrHistogram/HdrHistogram
|
||
|
* and released to the public domain, as explained at
|
||
|
* http://creativecommons.org/publicdomain/zero/1.0/
|
||
|
*/
|
||
|
const JsHistogram_1 = require("./JsHistogram");
|
||
|
const ByteBuffer_1 = require("./ByteBuffer");
|
||
|
const wasm_1 = require("./wasm");
|
||
|
// @ts-ignore
|
||
|
const base64 = require("base64-js");
|
||
|
const JsHistogram_encoding_1 = require("./JsHistogram.encoding");
|
||
|
const V2CompressedEncodingCookieBase = 0x1c849304;
|
||
|
const compressedEncodingCookie = V2CompressedEncodingCookieBase | 0x10; // LSBit of wordsize byte indicates TLZE Encoding
|
||
|
function decompress(data) {
|
||
|
const buffer = new ByteBuffer_1.default(data);
|
||
|
const initialTargetPosition = buffer.position;
|
||
|
const cookie = buffer.getInt32();
|
||
|
if ((cookie & ~0xf0) !== V2CompressedEncodingCookieBase) {
|
||
|
throw new Error("Encoding not supported, only V2 is supported");
|
||
|
}
|
||
|
const lengthOfCompressedContents = buffer.getInt32();
|
||
|
const uncompressedBuffer = JsHistogram_encoding_1.inflate(buffer.data.slice(initialTargetPosition + 8, initialTargetPosition + 8 + lengthOfCompressedContents));
|
||
|
return uncompressedBuffer;
|
||
|
}
|
||
|
exports.decompress = decompress;
|
||
|
exports.decodeFromCompressedBase64 = (base64String, bitBucketSize = 32, useWebAssembly = false, minBarForHighestTrackableValue = 0) => {
|
||
|
const data = base64.toByteArray(base64String.trim());
|
||
|
const uncompressedData = decompress(data);
|
||
|
if (useWebAssembly) {
|
||
|
return wasm_1.WasmHistogram.decode(uncompressedData, bitBucketSize, minBarForHighestTrackableValue);
|
||
|
}
|
||
|
return JsHistogram_1.JsHistogram.decode(uncompressedData, bitBucketSize, minBarForHighestTrackableValue);
|
||
|
};
|
||
|
function encodeWasmIntoCompressedBase64(compressionLevel) {
|
||
|
const compressionOptions = compressionLevel
|
||
|
? { level: compressionLevel }
|
||
|
: {};
|
||
|
const self = this;
|
||
|
const targetBuffer = ByteBuffer_1.default.allocate();
|
||
|
targetBuffer.putInt32(compressedEncodingCookie);
|
||
|
const uncompressedData = self.encode();
|
||
|
const compressedData = JsHistogram_encoding_1.deflate(uncompressedData, compressionOptions);
|
||
|
targetBuffer.putInt32(compressedData.byteLength);
|
||
|
targetBuffer.putArray(compressedData);
|
||
|
return base64.fromByteArray(targetBuffer.data);
|
||
|
}
|
||
|
wasm_1.WasmHistogram.prototype.encodeIntoCompressedBase64 = encodeWasmIntoCompressedBase64;
|
||
|
exports.encodeIntoCompressedBase64 = (histogram, compressionLevel) => {
|
||
|
if (histogram instanceof wasm_1.WasmHistogram) {
|
||
|
return histogram.encodeIntoCompressedBase64(compressionLevel);
|
||
|
}
|
||
|
if (histogram instanceof JsHistogram_1.JsHistogram) {
|
||
|
return histogram.encodeIntoCompressedBase64(compressionLevel);
|
||
|
}
|
||
|
throw new Error("Unsupported Histogram implementation");
|
||
|
};
|
||
|
//# sourceMappingURL=encoding.js.map
|