39 lines
851 B
JavaScript
39 lines
851 B
JavaScript
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function randomString(n,s){
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//
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// review..
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try{
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n = n || 16
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let b = new Uint8Array(n+1) // +1 for extra random value for initial start position
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crypto.getRandomValues(b)
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s = s || 'ABCDEFGHIJKLMNOPQRSTUWXYZabcdefghijklmnopqrstuvwxyz01234567890' //-_'
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let aa = []
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let ii = 0
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let len = s.length
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// note: this might be biased? or might be bad to add seq random numbers?
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for(let i = 0;i< b.length;i++){ // first value (index 0) to start in a random location.
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let v = b[i]
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ii += v
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if(i > 0){
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let iii = ii%len
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let vv = s[iii]
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if(!vv)
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conole.log('out of range?',iii)
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aa.push(vv)
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}
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}//for
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let r = aa.join('')
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return r
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}
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catch(e){
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//
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console.log('crypto not supported?')
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return Math.random().toString(36).substring(7) // till crypto bug fix?
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}
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}
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export default randomString
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