How to check playerprefs has actually written data?

I'm using playerprefs to save game state. If a user has decided to toggle on 'block 3rd party cookies and site data' in Chrome this will stop playerprefs actually saving anything in a webGL build. Specifically this is happening on itch.io because they save games on google storage rather than their servers.

I tried to add a check to see if playerprefs were *actually* writing like this:

Code (CSharp):

1.         PlayerPrefs.SetString (key, serialized);
2.         int randomInt = UnityEngine.Random.Range(1, int.MaxValue);
3.         PlayerPrefs.SetInt("SanityCheck",randomInt);
4.         PlayerPrefs.Save();
5.  
6.         //check that prefs are actually getting written
7.         int sanityCheck = PlayerPrefs.GetInt("SanityCheck",0);
8.         if(sanityCheck != randomInt){
9.               //show user error
10.         }

But ... this claims to always be working - I'm assuming because playerprefs is getting cached in memory. How can I check that the write really happened?

 

Hey there, I understand the issue, the question is what to do about it

Reading between the lines ... are you suggesting that I write a js function to add to my custom webGL template, to call from unity, that would run window.indexedDB.open() and report back to Unity any issue?

 

Hrm, I think this still might not work ... looking at the game page (https://scarybee.itch.io/slurpy-derpy?secret=AFUU9vxWIJ02rl9jFBK8ZinzfyY) it looks like the index.html is stored on itch.io (so would be 1st party) but the game data is on google storage (3rd party). So running anything from the index.html will give false positives.

I guess I can try running the js from the game code instead of writing it into the index.html file ... will give that a go.

 

Thanks for taking a look ... so it should work then. Will check and confirm.

 

I've tested this and ... it doesn't work (false positives), this is the URL https://scarybee.itch.io/slurpy-derpy?secret=AFUU9vxWIJ02rl9jFBK8ZinzfyY with the function check in it. I also tried running the js as an externalEval (which gives the IndexDB2 messages in console log) but as expected(?) this gives the same false result.

So, currently still stuck for a way to check if playerprefs are working or not.

 

Yuck, ok, I got this to work.

In a Start() function I'm calling this JS method, baked into my custom index.html

Code (JavaScript):

1.  
2.       var testDB;
3.       function checkIndexedDBAvailable () {
4.           try {
5.               var request = window.indexedDB.open("plsworkpls");
6.             request.onerror = function(event) {
7.                 console.log("failed to open IndexedDB onerror: "+event.target.errorCode);  
8.                 SendMessage('DataController', 'FailedToOpenIndexedDB', ''+event.target.errorCode);
9.             };
10.             request.onsuccess = function(event) {
11.                 console.log("IndexedDB available");
12.                 testDB = event.target.result;
13.             };
14.         }
15.         catch(err) {
16.             console.log("failed to open IndexedDB: "+err.message);
17.             SendMessage('DataController', 'FailedToOpenIndexedDB', ''+err.message);
18.         }
19.       }

Using this the onerror handler gets used if I'm blocking 3rd party cookies/data.

Things to note:

* The open() on indexDB requires a name
* The open is async so won't error immediately (in chrome at least)
* In chrome there is no error code so this will send an empty string back to Unity.
* This is way more work that it should have been

 

We also faced this issue now on Safari (our game runs in Facebook and can't access the indexedDB).
Is there any suggested workaround we could apply? for saving simple types (e.g: key / values)

 

We have actually implemented a workaround using localStorage. Could you perhaps tell me (since i am not a web dev), what are the pros/cons of using that (for storing key/values) ? (apart from what you specified)

Also, if PlayerPrefs are essentially simple-typed key-value pairs, why are you using IndexedDB for it and not localStorage for example?

 

@alexsuvorov We're seeing a similar problem in Chrome, in a facebook app, where PlayerPrefs at first works fine, and then after a while (haven't found the cause yet), we update some value (e.g. coins), and upon closing and relaunching the app, the change is not there anymore.

So for example, if players buy coins, they see the coins have been given. But upon relaunching the app, the coins vanish because the previous value is being read. (We are doing PlayerPrefs.Save() on every change to PlayerPrefs)

We have already tried to make a repro project, but couldn't reproduce. We do not believe we are putting too much data in PlayerPrefs, although we do not know how to check the size of the webgl playerprefs. Didn't see any playerprefs errors in console either. Any hints?

 

@alexsuvorov Hi alex, Yes. It saved fine, then at some point it is as if the playerprefs get corrupted and doesn't save to disk anymore. There was only one webgl tab open in the experiment.

We have now implemented a work around, where we use localStorage to save data instead. So far we didn't meet with the same problem after two days QA testing it.

 

@alexsuvorov The issue occurs randomly. But don't have exact steps how to reproduce. I used to be testing the app, and then all of a sudden, when I reboot the app I see old values rather than the latest ones. Then I go to clear the data related with the webgl app, and I see more than 1 indexedDB listed in chrome.

Before we switched to using LocalStorage, I was on 5.3.4p1.