29 lines
		
	
	
		
			859 B
		
	
	
	
		
			Markdown
		
	
	
	
		
		
			
		
	
	
			29 lines
		
	
	
		
			859 B
		
	
	
	
		
			Markdown
		
	
	
	
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								# minipass-sized
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								A Minipass stream that raises an error if you get a different number of
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								bytes than expected.
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								## USAGE
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								Use just like any old [minipass](http://npm.im/minipass) stream, but
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								provide a `size` option to the constructor.
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								The `size` option must be a positive integer, smaller than
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								`Number.MAX_SAFE_INTEGER`.
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								```js
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								const MinipassSized = require('minipass-sized')
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								// figure out how much data you expect to get
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								const expectedSize = +headers['content-length']
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								const stream = new MinipassSized({ size: expectedSize })
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								stream.on('error', er => {
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								  // if it's the wrong size, then this will raise an error with
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								  // { found: <number>, expect: <number>, code: 'EBADSIZE' }
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								})
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								response.pipe(stream)
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								```
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								Caveats: this does not work with `objectMode` streams, and will throw a
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								`TypeError` from the constructor if the size argument is missing or
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								invalid.
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