r2-utils-js
Version:
Readium 2 'utils' for NodeJS (TypeScript)
99 lines • 3.58 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.HttpZipReader = void 0;
const tslib_1 = require("tslib");
const debug_ = require("debug");
const request = require("request");
const requestPromise = require("request-promise-native");
const stream_1 = require("stream");
const yauzl = require("yauzl");
const BufferUtils_1 = require("../stream/BufferUtils");
const debug = debug_("r2:utils#zip/zip2RandomAccessReader_Http");
class HttpZipReader extends yauzl.RandomAccessReader {
constructor(url, byteLength) {
super();
this.url = url;
this.byteLength = byteLength;
this.firstBuffer = undefined;
this.firstBufferStart = 0;
this.firstBufferEnd = 0;
}
_readStreamForRange(start, end) {
if (this.firstBuffer && start >= this.firstBufferStart && end <= this.firstBufferEnd) {
const begin = start - this.firstBufferStart;
const stop = end - this.firstBufferStart;
return (0, BufferUtils_1.bufferToStream)(this.firstBuffer.slice(begin, stop));
}
const stream = new stream_1.PassThrough();
const lastByteIndex = end - 1;
const range = `${start}-${lastByteIndex}`;
const failure = (err) => {
debug(err);
};
const success = (res) => tslib_1.__awaiter(this, void 0, void 0, function* () {
if (res.statusCode && (res.statusCode < 200 || res.statusCode >= 300)) {
failure("HTTP CODE " + res.statusCode);
return;
}
if (this.firstBuffer) {
res.pipe(stream);
}
else {
let buffer;
try {
buffer = yield (0, BufferUtils_1.streamToBufferPromise)(res);
}
catch (err) {
debug(err);
stream.end();
return;
}
debug(`streamToBufferPromise: ${buffer.length}`);
this.firstBuffer = buffer;
this.firstBufferStart = start;
this.firstBufferEnd = end;
stream.write(buffer);
stream.end();
}
});
const needsStreamingResponse = true;
if (needsStreamingResponse) {
request.get({
headers: { Range: `bytes=${range}` },
method: "GET",
uri: this.url,
})
.on("response", (res) => tslib_1.__awaiter(this, void 0, void 0, function* () {
try {
yield success(res);
}
catch (successError) {
failure(successError);
return;
}
}))
.on("error", failure);
}
else {
(() => tslib_1.__awaiter(this, void 0, void 0, function* () {
let res;
try {
res = yield requestPromise({
headers: { Range: `bytes=${range}` },
method: "GET",
resolveWithFullResponse: true,
uri: this.url,
});
}
catch (err) {
failure(err);
return;
}
yield success(res);
}))();
}
return stream;
}
}
exports.HttpZipReader = HttpZipReader;
//# sourceMappingURL=zip2RandomAccessReader_Http.js.map