48 lines
1.9 KiB
JavaScript
48 lines
1.9 KiB
JavaScript
|
/*
|
||
|
|
Copyright 2018 Google LLC
|
||
|
|
|
||
|
|
Use of this source code is governed by an MIT-style
|
||
|
|
license that can be found in the LICENSE file or at
|
||
|
|
https://opensource.org/licenses/MIT.
|
||
|
|
*/
|
||
|
|
import { WorkboxError } from 'workbox-core/_private/WorkboxError.js';
|
||
|
|
import { assert } from 'workbox-core/_private/assert.js';
|
||
|
|
import '../_version.js';
|
||
|
|
/**
|
||
|
|
* @param {string} rangeHeader A Range: header value.
|
||
|
|
* @return {Object} An object with `start` and `end` properties, reflecting
|
||
|
|
* the parsed value of the Range: header. If either the `start` or `end` are
|
||
|
|
* omitted, then `null` will be returned.
|
||
|
|
*
|
||
|
|
* @private
|
||
|
|
*/
|
||
|
|
function parseRangeHeader(rangeHeader) {
|
||
|
|
if (process.env.NODE_ENV !== 'production') {
|
||
|
|
assert.isType(rangeHeader, 'string', {
|
||
|
|
moduleName: 'workbox-range-requests',
|
||
|
|
funcName: 'parseRangeHeader',
|
||
|
|
paramName: 'rangeHeader',
|
||
|
|
});
|
||
|
|
}
|
||
|
|
const normalizedRangeHeader = rangeHeader.trim().toLowerCase();
|
||
|
|
if (!normalizedRangeHeader.startsWith('bytes=')) {
|
||
|
|
throw new WorkboxError('unit-must-be-bytes', { normalizedRangeHeader });
|
||
|
|
}
|
||
|
|
// Specifying multiple ranges separate by commas is valid syntax, but this
|
||
|
|
// library only attempts to handle a single, contiguous sequence of bytes.
|
||
|
|
// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Range#Syntax
|
||
|
|
if (normalizedRangeHeader.includes(',')) {
|
||
|
|
throw new WorkboxError('single-range-only', { normalizedRangeHeader });
|
||
|
|
}
|
||
|
|
const rangeParts = /(\d*)-(\d*)/.exec(normalizedRangeHeader);
|
||
|
|
// We need either at least one of the start or end values.
|
||
|
|
if (!rangeParts || !(rangeParts[1] || rangeParts[2])) {
|
||
|
|
throw new WorkboxError('invalid-range-values', { normalizedRangeHeader });
|
||
|
|
}
|
||
|
|
return {
|
||
|
|
start: rangeParts[1] === '' ? undefined : Number(rangeParts[1]),
|
||
|
|
end: rangeParts[2] === '' ? undefined : Number(rangeParts[2]),
|
||
|
|
};
|
||
|
|
}
|
||
|
|
export { parseRangeHeader };
|