jsforce
Version:
Salesforce API Library for JavaScript
105 lines (104 loc) • 3.2 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.concatStreamsAsDuplex = exports.readAll = exports.createLazyStream = void 0;
const stream_1 = require("stream");
const logger_1 = require("./logger");
const logger = (0, logger_1.getLogger)('stream');
function createLazyStream() {
const ins = new stream_1.PassThrough();
const outs = new stream_1.PassThrough();
const stream = concatStreamsAsDuplex(ins, outs);
let piped = false;
const setStream = (str) => {
if (piped) {
throw new Error('stream is already piped to actual stream');
}
piped = true;
ins.pipe(str).pipe(outs);
};
return { stream, setStream };
}
exports.createLazyStream = createLazyStream;
class MemoryWriteStream extends stream_1.Writable {
_chunks;
_totalBytes;
constructor() {
super();
this._chunks = [];
this._totalBytes = 0;
}
_write(chunk, encoding, callback) {
this._chunks.push(chunk);
this._totalBytes += chunk.length;
callback();
}
_writev(data, callback) {
for (const { chunk } of data) {
this._chunks.push(chunk);
this._totalBytes += chunk.length;
}
callback();
}
toString(encoding = 'utf-8') {
return Buffer.concat(this._chunks).toString(encoding);
}
}
async function readAll(rs, encoding = 'utf-8') {
logger.debug('readAll: starting to read stream');
const start = Date.now();
return new Promise((resolve, reject) => {
const ws = new MemoryWriteStream();
rs.on('error', (err) => {
logger.error(`readAll: stream error: ${(err).message}`);
reject(err);
})
.pipe(ws)
.on('finish', () => {
logger.debug(`readAll: stream finished in ${Date.now() - start}ms`);
resolve(ws.toString(encoding));
});
});
}
exports.readAll = readAll;
class DuplexifiedStream extends stream_1.Duplex {
_writable;
_readable;
constructor(ws, rs, opts = {}) {
super({
writableObjectMode: opts.writableObjectMode ?? ws.writableObjectMode,
readableObjectMode: opts.readableObjectMode ?? rs.readableObjectMode,
});
this._writable = ws;
this._readable = rs;
ws.once('finish', () => {
this.end();
});
this.once('finish', () => {
ws.end();
});
rs.on('readable', () => {
this._readStream();
});
rs.once('end', () => {
this.push(null);
});
ws.on('error', (err) => this.emit('error', err));
rs.on('error', (err) => this.emit('error', err));
}
_write(chunk, encoding, callback) {
this._writable.write(chunk, encoding, callback);
}
_read(n) {
this._readStream(n);
}
_readStream(n) {
let data;
while ((data = this._readable.read(n)) !== null) {
this.push(data);
}
}
}
function concatStreamsAsDuplex(ws, rs, opts) {
return new DuplexifiedStream(ws, rs, opts);
}
exports.concatStreamsAsDuplex = concatStreamsAsDuplex;