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_webext-storageCall.js - Fail proof chrome.storage accessor.
// rev2 - https://gist.github.com/Noitidart/bcb964207ac370d3301720f3d5c9eb2b
var _storagecall_pendingset = {};
var _storagecall_callid = 1;
function storageCall(aArea, aAction, aKeys, aOptions) {
// because storage can fail, i created this, which goes until it doesnt fail
// aAction - string;enum[set,get,clear,remove]
// aKeys -
// if aAction "clear" then ignore
// if aAction "remove" then string/string[]
// if aAction "get" then null/string/string[]
// if aAction "set" then object
// aOptions - object
// maxtries - int;default:0 - set to 0 if you want it to try infinitely
// timebetween - int;default:50 - milliseconds
aOptions = aOptions ? aOptions : {};
const maxtries = aOptions.maxtries || 0;
const timebetween = aOptions.timebetween || 50;
const callid = _storagecall_callid++; // the id of this call to `storageCall` // only used for when `aAction` is "set"
if (aAction == 'set') {
// see if still trying to set any of these keys
for (var setkey in aKeys) {
_storagecall_pendingset[setkey] = callid;
}
}
return new Promise(function(resolve, reject) {
// start asnc-proc49399
var trycnt = 0;
var call = function() {
switch (aAction) {
case 'clear':
chrome.storage[aArea][aAction](check);
break;
case 'set':
// special processing
// start - block-link3191
// make sure that each this `callid` is still responsible for setting in `aKeys`
for (var setkey in aKeys) {
if (_storagecall_pendingset[setkey] !== callid) {
delete aKeys[setkey];
}
}
// end - block-link3191
if (!Object.keys(aKeys).length) resolve(); // no longer responsible, as another call to set - with the keys that this callid was responsible for - has been made, so lets say it succeeded // i `resolve` and not `reject` because, say i was still responsible for one of the keys, when that completes it will `resolve`
else chrome.storage[aArea][aAction](aKeys, check);
break;
default:
chrome.storage[aArea][aAction](aKeys, check);
}
};
var check = function(arg1) {
if (chrome.runtime.lastError) {
if (!maxtries || trycnt++ < maxtries) setTimeout(call, timebetween);
else reject(chrome.runtime.lastError); // `maxtries` reached
} else {
switch (aAction) {
case 'clear':
case 'remove':
// callback `check` triggred with no arguments
resolve();
case 'set':
// callback `check` triggred with no arguments - BUT special processing
// race condition I THINK - because i think setting storage internals is async - so what if another call came in and did the set while this one was in between `call` and `check`, so meaningi t was processing - and then this finished processing AFTER a new call to `storageCall('', 'set'` happend
// copy - block-link3191
// make sure that each this `callid` is still responsible for setting in `aKeys`
for (var setkey in aKeys) {
if (_storagecall_pendingset[setkey] !== callid) {
delete aKeys[setkey];
}
}
// end copy - block-link3191
// remove keys from `_storagecall_pendingset`
for (var setkey in aKeys) {
// assuming _storagecall_pendingset[setkey] === callid
delete _storagecall_pendingset[setkey];
}
// SPECIAL - udpate core.store
if (typeof(core) == 'object' && core.store) {
for (var setkey in aKeys) {
core.store[setkey] = aKeys[setkey];
}
}
resolve(aKeys);
break;
case 'get':
// callback `check` triggred with 1 argument
var storeds = arg1;
resolve(storeds);
break;
}
resolve(storeds);
}
};
call();
// end asnc-proc49399
});
}
@Noitidart
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