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@logtape/file

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File sink and rotating file sink for LogTape

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const require_rolldown_runtime = require('./_virtual/rolldown_runtime.cjs'); const require_snapshot = require('./snapshot.cjs'); const __logtape_logtape = require_rolldown_runtime.__toESM(require("@logtape/logtape")); const node_fs = require_rolldown_runtime.__toESM(require("node:fs")); const node_events = require_rolldown_runtime.__toESM(require("node:events")); //#region src/streamfilesink.ts /** * Create a high-performance stream-based file sink that writes log records to a file. * * This sink writes formatted records directly to a Node.js `WriteStream`. It * leverages Node.js stream buffering for efficient asynchronous writes without * blocking the main thread. * * ## Performance Characteristics * * - **High Performance**: Optimized for high-volume logging scenarios * - **Non-blocking**: Uses asynchronous I/O that doesn't block the main thread * - **Memory Efficient**: Uses the file stream buffer directly * - **Stream-based**: Leverages Node.js native stream optimizations * * ## When to Use * * Use this sink when you need: * - High-performance file logging for production applications * - Non-blocking I/O behavior for real-time applications * - Stream-buffered writes for high-volume scenarios * - Simple file output without complex buffering configuration * * For more control over buffering behavior, consider using {@link getFileSink} * instead, which provides options for buffer size, flush intervals, and * non-blocking modes. * * ## Example * * ```typescript * import { configure } from "@logtape/logtape"; * import { getStreamFileSink } from "@logtape/file"; * * await configure({ * sinks: { * file: getStreamFileSink("app.log", { * highWaterMark: 32768 // 32KB buffer for high-volume logging * }) * }, * loggers: [ * { category: ["myapp"], sinks: ["file"] } * ] * }); * ``` * * @param path The path to the file to write logs to. The file will be created * if it doesn't exist, or appended to if it does exist. * @param options Configuration options for the stream-based sink. * @returns A sink that writes formatted log records to the specified file. * The returned sink implements `AsyncDisposable` for proper resource cleanup * that waits for all data to be flushed to disk. * * @since 1.0.0 */ function getStreamFileSink(path, options = {}) { const highWaterMark = options.highWaterMark ?? 16384; const formatter = options.formatter ?? __logtape_logtape.defaultTextFormatter; const writeStream = (0, node_fs.createWriteStream)(path, { flags: "a", highWaterMark }); let disposed = false; let streamError; const handleStreamError = (error) => { streamError = error; }; writeStream.on("error", handleStreamError); const sink = (record) => { if (disposed) return; writeStream.write(formatter(record)); }; sink[Symbol.asyncDispose] = async () => { if (disposed) return; disposed = true; try { if (streamError != null) throw streamError; if (writeStream.writableNeedDrain && !writeStream.writableEnded) await (0, node_events.once)(writeStream, "drain"); if (streamError != null) throw streamError; if (writeStream.closed || writeStream.destroyed) return; const closePromise = (0, node_events.once)(writeStream, "close"); writeStream.end(); await closePromise; if (streamError != null) throw streamError; } finally { writeStream.off("error", handleStreamError); } }; return require_snapshot.markSinkAsImmediate(sink); } //#endregion exports.getStreamFileSink = getStreamFileSink;