UNPKG

@boost/log

Version:

Lightweight level based logging system.

217 lines (173 loc) 4.66 kB
import fs from 'node:fs'; import zlib from 'node:zlib'; import { Path, type PortablePath } from '@boost/common'; import { type Blueprint, portablePathSchema, type Schemas } from '@boost/common/optimal'; import { MAX_LOG_SIZE } from '../constants'; import { Transport } from '../Transport'; import type { TransportOptions } from '../types'; export interface FileTransportOptions extends TransportOptions { /** Apply gzip compression to the write stream. */ gzip?: boolean; /** * Maximum file size before rotating file. * Will create a backup and truncate the current file. Defaults to 10mb. */ maxSize?: number; /** Absolute file system path for the intended log file. */ path: PortablePath; } export class FileTransport< Options extends FileTransportOptions = FileTransportOptions, > extends Transport<Options> { readonly path: Path; stream?: NodeJS.WritableStream; protected buffer: string = ''; protected draining: boolean = false; protected lastSize: number = 0; protected rotating: boolean = false; constructor(options: Options) { super(options); this.path = Path.resolve(this.options.path); this.checkFolderRequirements(); } override blueprint(schemas: Schemas): Blueprint<FileTransportOptions> { const { bool, number } = schemas; return { ...super.blueprint(schemas), gzip: bool(), maxSize: number(MAX_LOG_SIZE).positive(), path: portablePathSchema.required(), }; } /** * Close the file stream and trigger the callback when finished. */ close(commit?: () => void) { const onClose = () => { commit?.(); this.stream = undefined; }; if (this.stream) { this.stream.once('finish', onClose).end(); } else { onClose(); } } /** * Open the file stream for writing. */ open(): NodeJS.WritableStream { if (this.stream) { return this.stream; } this.stream = this.createStream(); if (this.path.exists()) { this.lastSize = fs.statSync(this.path.path()).size; } if (this.buffer) { const message = this.buffer; this.buffer = ''; this.write(message); } return this.stream; } /** * Write a message to the file stream, and rotate files once written if necessary. */ write(message: string) { if (this.rotating) { this.buffer += message; return; } const stream = this.open(); const written = stream.write(message, 'utf8', () => { this.lastSize += Buffer.byteLength(message); this.checkIfNeedsRotation(); }); // istanbul ignore next if (!written) { this.draining = true; stream.once('drain', () => { this.draining = false; }); } } /** * Check that the parent folder exists and has the correct permissions. */ protected checkFolderRequirements() { fs.mkdirSync(this.path.parent().path(), { recursive: true }); } /** * Check if we should change and rotate files because of max size. */ protected checkIfNeedsRotation() { // @ts-expect-error Valid is defined if (this.options && this.lastSize > this.options.maxSize) { this.closeStreamAndRotateFile(); } } /** * Open and create a file stream for the defined path. * Apply file size and gzip checks. */ protected createStream() { const stream = fs.createWriteStream(this.path.path(), { encoding: 'utf8', flags: 'a', }); // Apply gzip compression to the stream if (this.options.gzip) { const gzip = zlib.createGzip(); gzip.pipe(stream); return gzip; } return stream; } /** * Return the file name with extension, of the newly rotated file. */ protected getRotatedFileName(): string { return this.path.name(); } /** * Count the number of files within path directory that matches the given file name. */ protected getNextIncrementCount(name: string): number { const files = fs.readdirSync(this.path.parent().path()); const pattern = new RegExp(`^${name}.\\d+$`, 'u'); let count = 0; files.forEach((file) => { if (file.match(pattern)) { count += 1; } }); return count; } /** * Close the open stream and attempt to rotate the file. */ protected closeStreamAndRotateFile() { // istanbul ignore next if (this.draining || this.rotating) { return; } this.rotating = true; this.close(() => { this.rotateFile(); this.rotating = false; }); } /** * Rotate the current file into a new file with an incremented name. */ protected rotateFile() { let fileName = this.getRotatedFileName(); if (this.options.gzip) { fileName += '.gz'; } fileName += `.${this.getNextIncrementCount(fileName)}`; fs.renameSync(this.path.path(), this.path.parent().append(fileName).path()); this.lastSize = 0; } }