23 lines
650 B
JavaScript
23 lines
650 B
JavaScript
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import assertString from './util/assertString';
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import merge from './util/merge';
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var notBase64 = /[^A-Z0-9+\/=]/i;
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var urlSafeBase64 = /^[A-Z0-9_\-]*$/i;
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var defaultBase64Options = {
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urlSafe: false
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};
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export default function isBase64(str, options) {
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assertString(str);
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options = merge(options, defaultBase64Options);
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var len = str.length;
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if (options.urlSafe) {
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return urlSafeBase64.test(str);
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}
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if (len % 4 !== 0 || notBase64.test(str)) {
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return false;
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}
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var firstPaddingChar = str.indexOf('=');
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return firstPaddingChar === -1 || firstPaddingChar === len - 1 || firstPaddingChar === len - 2 && str[len - 1] === '=';
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}
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