react-native/Libraries/Image/resolveAssetSource.js

93 lines
2.8 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule resolveAssetSource
* @flow
*
* Resolves an asset into a `source` for `Image`.
*/
'use strict';
const AssetRegistry = require('AssetRegistry');
const AssetSourceResolver = require('AssetSourceResolver');
const NativeModules = require('NativeModules');
import type { ResolvedAssetSource } from 'AssetSourceResolver';
let _customSourceTransformer, _serverURL, _bundleSourceURL;
function getDevServerURL(): ?string {
if (_serverURL === undefined) {
var scriptURL = NativeModules.SourceCode.scriptURL;
var match = scriptURL && scriptURL.match(/^https?:\/\/.*?\//);
if (match) {
// Bundle was loaded from network
_serverURL = match[0];
} else {
// Bundle was loaded from file
_serverURL = null;
}
}
return _serverURL;
}
function getBundleSourceURL(): ?string {
if (_bundleSourceURL === undefined) {
const scriptURL = NativeModules.SourceCode.scriptURL;
if (!scriptURL) {
// scriptURL is falsy, we have nothing to go on here
_bundleSourceURL = null;
return _bundleSourceURL;
}
if (scriptURL.startsWith('assets://')) {
// android: running from within assets, no offline path to use
_bundleSourceURL = null;
return _bundleSourceURL;
}
_bundleSourceURL = scriptURL.substring(0, scriptURL.lastIndexOf('/') + 1);
if (!scriptURL.startsWith('file://')) {
// Add file protocol in case we have an absolute file path and not a URL.
// This shouldn't really be necessary. scriptURL should be a URL.
_bundleSourceURL = 'file://' + _bundleSourceURL;
}
}
return _bundleSourceURL;
}
function setCustomSourceTransformer(
transformer: (resolver: AssetSourceResolver) => ResolvedAssetSource,
): void {
_customSourceTransformer = transformer;
}
/**
* `source` is either a number (opaque type returned by require('./foo.png'))
* or an `ImageSource` like { uri: '<http location || file path>' }
*/
function resolveAssetSource(source: any): ?ResolvedAssetSource {
if (typeof source === 'object') {
return source;
}
var asset = AssetRegistry.getAssetByID(source);
if (!asset) {
return null;
}
const resolver = new AssetSourceResolver(getDevServerURL(), getBundleSourceURL(), asset);
if (_customSourceTransformer) {
return _customSourceTransformer(resolver);
}
return resolver.defaultAsset();
}
module.exports = resolveAssetSource;
module.exports.pickScale = AssetSourceResolver.pickScale;
module.exports.setCustomSourceTransformer = setCustomSourceTransformer;