pdf.js/src/display/node_stream.js
Jonas Jenwald d4d933538b Re-factor setPDFNetworkStreamFactory, in src/display/api.js, to also accept an asynchronous function
As part of trying to reduce the usage of SystemJS in the development viewer, this patch is a necessary step that will allow removal of some `require` statements.

Currently this uses `SystemJS.import` in non-PRODUCTION mode, but it should be possible to replace those with standard *dynamic* `import` calls in the future.
2020-05-20 13:18:18 +02:00

464 lines
12 KiB
JavaScript

/* Copyright 2012 Mozilla Foundation
*
* Licensed 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.
*/
/* globals __non_webpack_require__ */
import {
AbortException,
assert,
createPromiseCapability,
MissingPDFException,
} from "../shared/util.js";
import {
extractFilenameFromHeader,
validateRangeRequestCapabilities,
} from "./network_utils.js";
if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
throw new Error(
'Module "./node_stream.js" shall not be used with MOZCENTRAL builds.'
);
}
const fs = __non_webpack_require__("fs");
const http = __non_webpack_require__("http");
const https = __non_webpack_require__("https");
const url = __non_webpack_require__("url");
const fileUriRegex = /^file:\/\/\/[a-zA-Z]:\//;
function parseUrl(sourceUrl) {
const parsedUrl = url.parse(sourceUrl);
if (parsedUrl.protocol === "file:" || parsedUrl.host) {
return parsedUrl;
}
// Prepending 'file:///' to Windows absolute path.
if (/^[a-z]:[/\\]/i.test(sourceUrl)) {
return url.parse(`file:///${sourceUrl}`);
}
// Changes protocol to 'file:' if url refers to filesystem.
if (!parsedUrl.host) {
parsedUrl.protocol = "file:";
}
return parsedUrl;
}
class PDFNodeStream {
constructor(source) {
this.source = source;
this.url = parseUrl(source.url);
this.isHttp =
this.url.protocol === "http:" || this.url.protocol === "https:";
// Check if url refers to filesystem.
this.isFsUrl = this.url.protocol === "file:";
this.httpHeaders = (this.isHttp && source.httpHeaders) || {};
this._fullRequestReader = null;
this._rangeRequestReaders = [];
}
get _progressiveDataLength() {
return this._fullRequestReader ? this._fullRequestReader._loaded : 0;
}
getFullReader() {
assert(
!this._fullRequestReader,
"PDFNodeStream.getFullReader can only be called once."
);
this._fullRequestReader = this.isFsUrl
? new PDFNodeStreamFsFullReader(this)
: new PDFNodeStreamFullReader(this);
return this._fullRequestReader;
}
getRangeReader(start, end) {
if (end <= this._progressiveDataLength) {
return null;
}
const rangeReader = this.isFsUrl
? new PDFNodeStreamFsRangeReader(this, start, end)
: new PDFNodeStreamRangeReader(this, start, end);
this._rangeRequestReaders.push(rangeReader);
return rangeReader;
}
cancelAllRequests(reason) {
if (this._fullRequestReader) {
this._fullRequestReader.cancel(reason);
}
const readers = this._rangeRequestReaders.slice(0);
readers.forEach(function (reader) {
reader.cancel(reason);
});
}
}
class BaseFullReader {
constructor(stream) {
this._url = stream.url;
this._done = false;
this._storedError = null;
this.onProgress = null;
const source = stream.source;
this._contentLength = source.length; // optional
this._loaded = 0;
this._filename = null;
this._disableRange = source.disableRange || false;
this._rangeChunkSize = source.rangeChunkSize;
if (!this._rangeChunkSize && !this._disableRange) {
this._disableRange = true;
}
this._isStreamingSupported = !source.disableStream;
this._isRangeSupported = !source.disableRange;
this._readableStream = null;
this._readCapability = createPromiseCapability();
this._headersCapability = createPromiseCapability();
}
get headersReady() {
return this._headersCapability.promise;
}
get filename() {
return this._filename;
}
get contentLength() {
return this._contentLength;
}
get isRangeSupported() {
return this._isRangeSupported;
}
get isStreamingSupported() {
return this._isStreamingSupported;
}
async read() {
await this._readCapability.promise;
if (this._done) {
return { value: undefined, done: true };
}
if (this._storedError) {
throw this._storedError;
}
const chunk = this._readableStream.read();
if (chunk === null) {
this._readCapability = createPromiseCapability();
return this.read();
}
this._loaded += chunk.length;
if (this.onProgress) {
this.onProgress({
loaded: this._loaded,
total: this._contentLength,
});
}
// Ensure that `read()` method returns ArrayBuffer.
const buffer = new Uint8Array(chunk).buffer;
return { value: buffer, done: false };
}
cancel(reason) {
// Call `this._error()` method when cancel is called
// before _readableStream is set.
if (!this._readableStream) {
this._error(reason);
return;
}
this._readableStream.destroy(reason);
}
_error(reason) {
this._storedError = reason;
this._readCapability.resolve();
}
_setReadableStream(readableStream) {
this._readableStream = readableStream;
readableStream.on("readable", () => {
this._readCapability.resolve();
});
readableStream.on("end", () => {
// Destroy readable to minimize resource usage.
readableStream.destroy();
this._done = true;
this._readCapability.resolve();
});
readableStream.on("error", reason => {
this._error(reason);
});
// We need to stop reading when range is supported and streaming is
// disabled.
if (!this._isStreamingSupported && this._isRangeSupported) {
this._error(new AbortException("streaming is disabled"));
}
// Destroy ReadableStream if already in errored state.
if (this._storedError) {
this._readableStream.destroy(this._storedError);
}
}
}
class BaseRangeReader {
constructor(stream) {
this._url = stream.url;
this._done = false;
this._storedError = null;
this.onProgress = null;
this._loaded = 0;
this._readableStream = null;
this._readCapability = createPromiseCapability();
const source = stream.source;
this._isStreamingSupported = !source.disableStream;
}
get isStreamingSupported() {
return this._isStreamingSupported;
}
async read() {
await this._readCapability.promise;
if (this._done) {
return { value: undefined, done: true };
}
if (this._storedError) {
throw this._storedError;
}
const chunk = this._readableStream.read();
if (chunk === null) {
this._readCapability = createPromiseCapability();
return this.read();
}
this._loaded += chunk.length;
if (this.onProgress) {
this.onProgress({ loaded: this._loaded });
}
// Ensure that `read()` method returns ArrayBuffer.
const buffer = new Uint8Array(chunk).buffer;
return { value: buffer, done: false };
}
cancel(reason) {
// Call `this._error()` method when cancel is called
// before _readableStream is set.
if (!this._readableStream) {
this._error(reason);
return;
}
this._readableStream.destroy(reason);
}
_error(reason) {
this._storedError = reason;
this._readCapability.resolve();
}
_setReadableStream(readableStream) {
this._readableStream = readableStream;
readableStream.on("readable", () => {
this._readCapability.resolve();
});
readableStream.on("end", () => {
// Destroy readableStream to minimize resource usage.
readableStream.destroy();
this._done = true;
this._readCapability.resolve();
});
readableStream.on("error", reason => {
this._error(reason);
});
// Destroy readableStream if already in errored state.
if (this._storedError) {
this._readableStream.destroy(this._storedError);
}
}
}
function createRequestOptions(parsedUrl, headers) {
return {
protocol: parsedUrl.protocol,
auth: parsedUrl.auth,
host: parsedUrl.hostname,
port: parsedUrl.port,
path: parsedUrl.path,
method: "GET",
headers,
};
}
class PDFNodeStreamFullReader extends BaseFullReader {
constructor(stream) {
super(stream);
const handleResponse = response => {
if (response.statusCode === 404) {
const error = new MissingPDFException(`Missing PDF "${this._url}".`);
this._storedError = error;
this._headersCapability.reject(error);
return;
}
this._headersCapability.resolve();
this._setReadableStream(response);
const getResponseHeader = name => {
// Make sure that headers name are in lower case, as mentioned
// here: https://nodejs.org/api/http.html#http_message_headers.
return this._readableStream.headers[name.toLowerCase()];
};
const {
allowRangeRequests,
suggestedLength,
} = validateRangeRequestCapabilities({
getResponseHeader,
isHttp: stream.isHttp,
rangeChunkSize: this._rangeChunkSize,
disableRange: this._disableRange,
});
this._isRangeSupported = allowRangeRequests;
// Setting right content length.
this._contentLength = suggestedLength || this._contentLength;
this._filename = extractFilenameFromHeader(getResponseHeader);
};
this._request = null;
if (this._url.protocol === "http:") {
this._request = http.request(
createRequestOptions(this._url, stream.httpHeaders),
handleResponse
);
} else {
this._request = https.request(
createRequestOptions(this._url, stream.httpHeaders),
handleResponse
);
}
this._request.on("error", reason => {
this._storedError = reason;
this._headersCapability.reject(reason);
});
// Note: `request.end(data)` is used to write `data` to request body
// and notify end of request. But one should always call `request.end()`
// even if there is no data to write -- (to notify the end of request).
this._request.end();
}
}
class PDFNodeStreamRangeReader extends BaseRangeReader {
constructor(stream, start, end) {
super(stream);
this._httpHeaders = {};
for (const property in stream.httpHeaders) {
const value = stream.httpHeaders[property];
if (typeof value === "undefined") {
continue;
}
this._httpHeaders[property] = value;
}
this._httpHeaders.Range = `bytes=${start}-${end - 1}`;
const handleResponse = response => {
if (response.statusCode === 404) {
const error = new MissingPDFException(`Missing PDF "${this._url}".`);
this._storedError = error;
return;
}
this._setReadableStream(response);
};
this._request = null;
if (this._url.protocol === "http:") {
this._request = http.request(
createRequestOptions(this._url, this._httpHeaders),
handleResponse
);
} else {
this._request = https.request(
createRequestOptions(this._url, this._httpHeaders),
handleResponse
);
}
this._request.on("error", reason => {
this._storedError = reason;
});
this._request.end();
}
}
class PDFNodeStreamFsFullReader extends BaseFullReader {
constructor(stream) {
super(stream);
let path = decodeURIComponent(this._url.path);
// Remove the extra slash to get right path from url like `file:///C:/`
if (fileUriRegex.test(this._url.href)) {
path = path.replace(/^\//, "");
}
fs.lstat(path, (error, stat) => {
if (error) {
if (error.code === "ENOENT") {
error = new MissingPDFException(`Missing PDF "${path}".`);
}
this._storedError = error;
this._headersCapability.reject(error);
return;
}
// Setting right content length.
this._contentLength = stat.size;
this._setReadableStream(fs.createReadStream(path));
this._headersCapability.resolve();
});
}
}
class PDFNodeStreamFsRangeReader extends BaseRangeReader {
constructor(stream, start, end) {
super(stream);
let path = decodeURIComponent(this._url.path);
// Remove the extra slash to get right path from url like `file:///C:/`
if (fileUriRegex.test(this._url.href)) {
path = path.replace(/^\//, "");
}
this._setReadableStream(fs.createReadStream(path, { start, end: end - 1 }));
}
}
export { PDFNodeStream };