@memlab/api
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JavaScript
;
/**
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @format
* @oncall memory_lab
*/
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const core_1 = require("@memlab/core");
const fs_extra_1 = __importDefault(require("fs-extra"));
const core_2 = require("@memlab/core");
const BaseResultReader_1 = __importDefault(require("./BaseResultReader"));
/**
* A utility entity to read all MemLab files generated from
* baseline, target and final heap snapshots.
*
* The most useful feature of this class is when you have
* three separate snapshots (baseline, target, and final)
* that are not taken from MemLab, but you still would
* like to use the `findLeaks` to detect memory leaks:
*
* ```javascript
* const {SnapshotResultReader, findLeaks} = require('@memlab/api');
*
* // baseline, target, and final are file paths of heap snapshot files
* const reader = SnapshotResultReader.fromSnapshots(baseline, target, final);
* const leaks = await findLeaks(reader);
* ```
*/
class SnapshotResultReader extends BaseResultReader_1.default {
/**
* build a result reader
* @param workDir absolute path of the directory where the data
* and generated files of the memlab run were stored
*/
constructor(baselineSnapshot, targetSnapshot, finalSnapshot) {
const fileManager = new core_2.FileManager();
const workDir = fileManager.generateTmpHeapDir();
fs_extra_1.default.ensureDirSync(workDir);
super(workDir);
this.baselineSnapshot = baselineSnapshot;
this.targetSnapshot = targetSnapshot;
this.finalSnapshot = finalSnapshot;
this.checkSnapshotFiles();
this.createMetaFilesOnDisk(fileManager, workDir);
}
createMetaFilesOnDisk(fileManager, workDir) {
fileManager.initDirs(core_1.config, { workDir });
const visitOrder = this.getInteractionSteps();
const snapSeqFile = fileManager.getSnapshotSequenceMetaFile({ workDir });
fs_extra_1.default.writeFileSync(snapSeqFile, JSON.stringify(visitOrder, null, 2), 'UTF-8');
}
checkSnapshotFiles() {
if (!fs_extra_1.default.existsSync(this.baselineSnapshot) ||
!fs_extra_1.default.existsSync(this.targetSnapshot) ||
!fs_extra_1.default.existsSync(this.finalSnapshot)) {
throw core_2.utils.haltOrThrow('invalid file path of baseline, target, or final heap snapshots');
}
}
/**
* Build a result reader from baseline, target, and final heap snapshot files.
* The three snapshot files do not have to be in the same directory.
* @param baselineSnapshot file path of the baseline heap snapshot
* @param targetSnapshot file path of the target heap snapshot
* @param finalSnapshot file path of the final heap snapshot
* @returns the ResultReader instance
*
* * **Examples**:
* ```javascript
* const {SnapshotResultReader, findLeaks} = require('@memlab/api');
*
* // baseline, target, and final are file paths of heap snapshot files
* const reader = SnapshotResultReader.fromSnapshots(baseline, target, final);
* const leaks = await findLeaks(reader);
* ```
*/
static fromSnapshots(baselineSnapshot, targetSnapshot, finalSnapshot) {
return new SnapshotResultReader(baselineSnapshot, targetSnapshot, finalSnapshot);
}
/**
* @internal
*/
static from(workDir = '') {
throw core_2.utils.haltOrThrow('SnapshotResultReader.from is not supported');
return new BaseResultReader_1.default(workDir);
}
/**
* get all snapshot files related to this SnapshotResultReader
* @returns an array of snapshot file's absolute path
*
* * **Examples**:
* ```javascript
* const {SnapshotResultReader} = require('@memlab/api');
*
* // baseline, target, and final are file paths of heap snapshot files
* const reader = SnapshotResultReader.fromSnapshots(baseline, target, final);
* const paths = reader.getSnapshotFiles();
* ```
*/
getSnapshotFiles() {
return [this.baselineSnapshot, this.targetSnapshot, this.finalSnapshot];
}
/**
* @internal
*/
getSnapshotFileDir() {
throw core_2.utils.haltOrThrow('SnapshotResultReader getSnapshotFileDir() method is not supported');
return '';
}
/**
* browser interaction step sequence
* @returns an array of browser interaction step information
*
* * **Examples**:
* ```javascript
* const {SnapshotResultReader} = require('@memlab/api');
*
* // baseline, target, and final are file paths of heap snapshot files
* const reader = SnapshotResultReader.fromSnapshots(baseline, target, final);
* const paths = reader.getInteractionSteps();
* ```
*/
getInteractionSteps() {
return this.fileManager.createVisitOrderWithSnapshots(this.baselineSnapshot, this.targetSnapshot, this.finalSnapshot);
}
/**
* @internal
* general meta data of the browser interaction run
* @returns meta data about the entire browser interaction
*
* * **Examples**:
* ```javascript
* const {SnapshotResultReader} = require('@memlab/api');
*
* // baseline, target, and final are file paths of heap snapshot files
* const reader = SnapshotResultReader.fromSnapshots(baseline, target, final);
* const metaInfo = reader.getRunMetaInfo();
* ```
*/
getRunMetaInfo() {
return new core_2.RunMetaInfoManager().loadRunMetaExternalTemplate();
}
/**
* @internal
*/
cleanup() {
// do nothing
}
}
exports.default = SnapshotResultReader;