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// 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.
import { Duplex, DuplexOptions } from 'stream';
import { AsyncByteStream } from '../../io/stream.js';
import { RecordBatchWriter } from '../../ipc/writer.js';
import { TypeMap } from '../../type.js';
/** @ignore */
export function recordBatchWriterThroughNodeStream<T extends TypeMap = any>(this: typeof RecordBatchWriter, options?: DuplexOptions & { autoDestroy: boolean }) {
return new RecordBatchWriterDuplex(new this<T>(options));
}
/** @ignore */
type CB = (error?: Error | null | undefined) => void;
/** @ignore */
class RecordBatchWriterDuplex<T extends TypeMap = any> extends Duplex {
private _pulling = false;
private _reader: AsyncByteStream | null;
private _writer: RecordBatchWriter | null;
constructor(writer: RecordBatchWriter<T>, options?: DuplexOptions) {
super({ allowHalfOpen: false, ...options, writableObjectMode: true, readableObjectMode: false });
this._writer = writer;
this._reader = new AsyncByteStream(writer);
}
_final(cb?: CB) {
const writer = this._writer;
writer?.close();
cb && cb();
}
_write(x: any, _: string, cb: CB) {
const writer = this._writer;
writer?.write(x);
cb && cb();
return true;
}
_read(size: number) {
const it = this._reader;
if (it && !this._pulling && (this._pulling = true)) {
(async () => this._pulling = await this._pull(size, it))();
}
}
_destroy(err: Error | null, cb: (error: Error | null) => void) {
const writer = this._writer;
if (writer) { err ? writer.abort(err) : writer.close(); }
cb(this._reader = this._writer = null);
}
async _pull(size: number, reader: AsyncByteStream) {
let r: IteratorResult<Uint8Array> | null = null;
while (this.readable && !(r = await reader.next(size || null)).done) {
if (size != null && r.value) {
size -= r.value.byteLength;
}
if (!this.push(r.value) || size <= 0) { break; }
}
if ((r?.done || !this.readable)) {
this.push(null);
await reader.cancel();
}
return !this.readable;
}
}
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