js/bin/file-to-stream.js

#! /usr/bin/env node

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

// @ts-check

const fs = require('fs');
const path = require('path');
const eos = require('util').promisify(require('stream').finished);
const extension = process.env.ARROW_JS_DEBUG === 'src' ? '.ts' : '';
const { RecordBatchReader, RecordBatchStreamWriter } = require(`../index${extension}`);

(async () => {

    const readable = process.argv.length < 3 ? process.stdin : fs.createReadStream(path.resolve(process.argv[2]));
    const writable = process.argv.length < 4 ? process.stdout : fs.createWriteStream(path.resolve(process.argv[3]));

    const fileToStream = readable
        .pipe(RecordBatchReader.throughNode())
        .pipe(RecordBatchStreamWriter.throughNode())
        .pipe(writable);

    await eos(fileToStream);

})().catch((e) => { console.error(e); process.exit(1); });