@signalk/streams/dist/liner.js

Utilities for handling streams of Signal K data

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
const stream_1 = require("stream");
class Liner extends stream_1.Transform {
    lineSeparator;
    lastLineData = null;
    constructor(options = {}) {
        super({ objectMode: true });
        this.lineSeparator = options.lineSeparator ?? '\n';
    }
    _transform(chunk, encoding, done) {
        let data = chunk.toString();
        if (this.lastLineData) {
            data = this.lastLineData + data;
        }
        const lines = data.split(this.lineSeparator);
        this.lastLineData = lines.splice(lines.length - 1, 1)[0] ?? null;
        if (this.lastLineData && this.lastLineData.length > 2048) {
            console.error('Are you sure you are using the correct line terminator? Not going to handle lines longer than 2048 chars.');
            this.lastLineData = '';
        }
        for (const line of lines) {
            this.push(line);
        }
        done();
    }
    _flush(done) {
        if (this.lastLineData) {
            this.push(this.lastLineData);
        }
        this.lastLineData = null;
        done();
    }
}
exports.default = Liner;