24 lines
797 B
JavaScript
24 lines
797 B
JavaScript
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'use strict'
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const { MAX_MSGID } = require('../constants')
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/**
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* Returns a function that generates message identifiers. According to RFC 4511
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* the identifers should be `(0, MAX_MSGID)`. The returned function handles
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* this and wraps around when the maximum has been reached.
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*
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* @param {integer} [start=0] Starting number in the identifier sequence.
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*
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* @returns {function} This function accepts no parameters and returns an
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* increasing sequence identifier each invocation until it reaches the maximum
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* identifier. At this point the sequence starts over.
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*/
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module.exports = function idGeneratorFactory (start = 0) {
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let currentID = start
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return function nextID () {
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const nextID = currentID + 1
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currentID = (nextID >= MAX_MSGID) ? 1 : nextID
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return currentID
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}
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}
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