pubnub
Version:
Publish & Subscribe Real-time Messaging with PubNub
183 lines (182 loc) • 7.18 kB
JavaScript
;
/**
* PubNub package utilities module.
*
* @internal
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.messageFingerprint = exports.adjustedTimetokenBy = exports.referenceSubscribeTimetoken = exports.subscriptionTimetokenFromReference = exports.queryStringFromObject = exports.findUniqueCommonElements = exports.removeSingleOccurrence = exports.encodeNames = exports.encodeString = void 0;
/**
* Percent-encode input string.
*
* **Note:** Encode content in accordance of the `PubNub` service requirements.
*
* @param input - Source string or number for encoding.
*
* @returns Percent-encoded string.
*
* @internal
*/
const encodeString = (input) => {
return encodeURIComponent(input).replace(/[!~*'()]/g, (x) => `%${x.charCodeAt(0).toString(16).toUpperCase()}`);
};
exports.encodeString = encodeString;
/**
* Percent-encode list of names (channels).
*
* @param names - List of names which should be encoded.
*
* @param [defaultString] - String which should be used in case if {@link names} is empty.
*
* @returns String which contains encoded names joined by non-encoded `,`.
*
* @internal
*/
const encodeNames = (names, defaultString) => {
const encodedNames = names.map((name) => (0, exports.encodeString)(name));
return encodedNames.length ? encodedNames.join(',') : (defaultString !== null && defaultString !== void 0 ? defaultString : '');
};
exports.encodeNames = encodeNames;
/**
* @internal
*/
const removeSingleOccurrence = (source, elementsToRemove) => {
const removed = Object.fromEntries(elementsToRemove.map((prop) => [prop, false]));
return source.filter((e) => {
if (elementsToRemove.includes(e) && !removed[e]) {
removed[e] = true;
return false;
}
return true;
});
};
exports.removeSingleOccurrence = removeSingleOccurrence;
/**
* @internal
*/
const findUniqueCommonElements = (a, b) => {
return [...a].filter((value) => b.includes(value) && a.indexOf(value) === a.lastIndexOf(value) && b.indexOf(value) === b.lastIndexOf(value));
};
exports.findUniqueCommonElements = findUniqueCommonElements;
/**
* Transform query key / value pairs to the string.
*
* @param query - Key / value pairs of the request query parameters.
*
* @returns Stringified query key / value pairs.
*
* @internal
*/
const queryStringFromObject = (query) => {
return Object.keys(query)
.map((key) => {
const queryValue = query[key];
if (!Array.isArray(queryValue))
return `${key}=${(0, exports.encodeString)(queryValue)}`;
return queryValue.map((value) => `${key}=${(0, exports.encodeString)(value)}`).join('&');
})
.join('&');
};
exports.queryStringFromObject = queryStringFromObject;
/**
* Adjust `timetoken` to represent current time in PubNub's high-precision time format.
*
* @param timetoken - Timetoken recently used for subscribe long-poll request.
* @param [referenceTimetoken] - Previously computed reference timetoken.
*
* @returns Adjusted timetoken if recent timetoken available.
*/
const subscriptionTimetokenFromReference = (timetoken, referenceTimetoken) => {
if (referenceTimetoken === '0' || timetoken === '0')
return undefined;
const timetokenDiff = (0, exports.adjustedTimetokenBy)(`${Date.now()}0000`, referenceTimetoken, false);
return (0, exports.adjustedTimetokenBy)(timetoken, timetokenDiff, true);
};
exports.subscriptionTimetokenFromReference = subscriptionTimetokenFromReference;
/**
* Create reference timetoken based on subscribe timetoken and the user's local time.
*
* Subscription-based reference timetoken allows later computing approximate timetoken at any point in time.
*
* @param [serviceTimetoken] - Timetoken received from the PubNub subscribe service.
* @param [catchUpTimetoken] - Previously stored or user-provided catch-up timetoken.
* @param [referenceTimetoken] - Previously computed reference timetoken. **Important:** This value should be used
* in the case of restore because the actual time when service and catch-up timetokens are received is really
* different from the current local time.
*
* @returns Reference timetoken.
*/
const referenceSubscribeTimetoken = (serviceTimetoken, catchUpTimetoken, referenceTimetoken) => {
if (!serviceTimetoken || serviceTimetoken.length === 0)
return undefined;
if (catchUpTimetoken && catchUpTimetoken.length > 0 && catchUpTimetoken !== '0') {
// Compensate reference timetoken because catch-up timetoken has been used.
const timetokensDiff = (0, exports.adjustedTimetokenBy)(serviceTimetoken, catchUpTimetoken, false);
return (0, exports.adjustedTimetokenBy)(referenceTimetoken !== null && referenceTimetoken !== void 0 ? referenceTimetoken : `${Date.now()}0000`, timetokensDiff.replace('-', ''), Number(timetokensDiff) < 0);
}
else if (referenceTimetoken && referenceTimetoken.length > 0 && referenceTimetoken !== '0')
return referenceTimetoken;
else
return `${Date.now()}0000`;
};
exports.referenceSubscribeTimetoken = referenceSubscribeTimetoken;
/**
* High-precision time token adjustment.
*
* @param timetoken - Source timetoken which should be adjusted.
* @param value - Value in nanoseconds which should be used for source timetoken adjustment.
* @param increment - Whether source timetoken should be incremented or decremented.
*
* @returns Adjusted high-precision PubNub timetoken.
*/
const adjustedTimetokenBy = (timetoken, value, increment) => {
// Normalize value to the PubNub's high-precision time format.
if (value.startsWith('-')) {
value = value.replace('-', '');
increment = false;
}
value = value.padStart(17, '0');
const secA = timetoken.slice(0, 10);
const tickA = timetoken.slice(10, 17);
const secB = value.slice(0, 10);
const tickB = value.slice(10, 17);
let seconds = Number(secA);
let ticks = Number(tickA);
seconds += Number(secB) * (increment ? 1 : -1);
ticks += Number(tickB) * (increment ? 1 : -1);
if (ticks >= 10000000) {
seconds += Math.floor(ticks / 10000000);
ticks %= 10000000;
}
else if (ticks < 0) {
if (seconds > 0) {
seconds -= 1;
ticks += 10000000;
}
else if (seconds < 0)
ticks *= -1;
}
else if (seconds < 0 && ticks > 0) {
seconds += 1;
ticks = 10000000 - ticks;
}
return seconds !== 0 ? `${seconds}${`${ticks}`.padStart(7, '0')}` : `${ticks}`;
};
exports.adjustedTimetokenBy = adjustedTimetokenBy;
/**
* Compute received update (message, event) fingerprint.
*
* @param input - Data payload from subscribe API response.
*
* @returns Received update fingerprint.
*/
const messageFingerprint = (input) => {
const msg = typeof input !== 'string' ? JSON.stringify(input) : input;
const mfp = new Uint32Array(1);
let walk = 0;
let len = msg.length;
while (len-- > 0)
mfp[0] = (mfp[0] << 5) - mfp[0] + msg.charCodeAt(walk++);
return mfp[0].toString(16).padStart(8, '0');
};
exports.messageFingerprint = messageFingerprint;