0760d17d82
Given the chunks coming from imagemagick are getting stored memory and then tucked into a cache, this function could as easily return a buffer via callback. Streaming is just making it more complex. (And trickier to test!)
37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
var gm = require('gm');
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var LruCache = require('./lru-cache.js');
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var imageMagick = gm.subClass({ imageMagick: true });
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// The following is an arbitrary limit (~1.5MB, 1.5kB/image).
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var imgCache = new LruCache(1000);
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module.exports = function (svg, format, callback) {
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var cacheIndex = format + svg;
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if (imgCache.has(cacheIndex)) {
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// We own a cache for this svg conversion.
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var result = imgCache.get(cacheIndex);
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callback(result);
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return;
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}
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var buf = Buffer.from('<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' + svg);
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var stream = imageMagick(buf, 'image.' + format)
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.density(90)
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.background(format === 'jpg' ? '#FFFFFF' : 'none')
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.flatten()
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.stream(format, function (err, stdout, stderr) {
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if (err) { console.error(err); return; }
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var chunks = [];
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stdout.on('data', function(chunk) { chunks.push(chunk); });
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stdout.on('finish', function() {
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var result = Buffer.concat(chunks);
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imgCache.set(cacheIndex, result);
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callback(result);
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});
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});
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};
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// To simplify testing.
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module.exports._imgCache = imgCache;
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