mirror of
https://github.com/scratchfoundation/scratch-parser.git
synced 2025-08-28 22:18:45 -04:00
7f8672dfbc
Refactor unpack and main exported function to return optional zip, if originally provided, in addition to the validated project. BREAKING CHANGE: Change to main api to return originally provided zip (or null if string was provided) along with validated project, in a 2-element array.
49 lines
1.5 KiB
JavaScript
49 lines
1.5 KiB
JavaScript
var zip = require('./zip');
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/**
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* If input a buffer, transforms buffer into a UTF-8 string.
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* If input is encoded in ZIP format, the input will be extracted and decoded.
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* If input is a string, passes that string along to the given callback.
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*
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* @param {Buffer | string} Input
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*
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* @return {String}
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*/
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module.exports = function (input, callback) {
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if (typeof input === 'string') {
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// Pass string to callback
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return callback(null, [input, null]);
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}
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// Validate input type
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var typeError = 'Input must be a Buffer or a string.';
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if (!Buffer.isBuffer(input)) {
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try {
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input = new Buffer(input);
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} catch (e) {
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return callback(typeError);
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}
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}
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// Determine format
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// We don't use the file suffix as this is unreliable and mine-type
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// information is unavailable from Scratch's project CDN. Instead, we look
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// at the first few bytes from the provided buffer (byte signature).
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// https://en.wikipedia.org/wiki/List_of_file_signatures
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var signature = input.slice(0, 3).join(' ');
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var isLegacy = false;
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var isZip = false;
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if (signature.indexOf('83 99 114') === 0) isLegacy = true;
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if (signature.indexOf('80 75') === 0) isZip = true;
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// If not legacy or zip, convert buffer to UTF-8 string and return
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if (!isZip && !isLegacy) {
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return callback(null, [input.toString('utf-8'), null]);
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}
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// Return error if legacy encoding detected
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if (isLegacy) return callback('Parser only supports Scratch 2.X');
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zip(input, callback);
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};
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