Function tailLog

src/ops/lifecycle.js:654–689

(lines)

}

function tailLog(lines) {
    if (!fs.existsSync(LOG_FILE)) return { error: 'No log file' };
    try {
        const n = parseInt(lines, 10) || 20;
        const fd = fs.openSync(LOG_FILE, 'r');
        var content = '';
        try {
            const stat = fs.fstatSync(fd);
            if (stat.size > 0) {
                const chunkSize = 64 * 1024;
                let position = stat.size;
                let collected = '';
                let lineCount = 0;
                while (position > 0 && lineCount <= n) {
                    const readSize = Math.min(chunkSize, position);
                    position -= readSize;
                    const buf = Buffer.alloc(readSize);
                    fs.readSync(fd, buf, 0, readSize, position);
                    collected = buf.toString('utf8') + collected;
                    lineCount = collected.split('\n').length - 1;
                }
                const rows = collected.split('\n');
                if (rows.length > 0 && rows[rows.length - 1] === '') rows.pop();
                content = rows.slice(-n).join('\n');
            }
        } finally {
            fs.closeSync(fd);
        }
        return {
            file: path.relative(WORKSPACE_ROOT, LOG_FILE),
            content: content
        };
    } catch (e) {
        return { error: e.message };
    }
}

function checkHealth() {
    var pids = getOwnedLoopPids(getRunningPids());