Why some method update are rejected from local version?

[passio]

Hello all, I use the svelte-motoko-starter projet.
After 2 days, it became a battle… and the more time I spend, the less I can give up. Now I’m one millimeter away from success

I’m trying to use the Auth.svelte file to make some calls in local.
So, in my main.mo, i have :
From : http://rkp4c-7iaaa-aaaaa-aaaca-cai.localhost:8000/ OR http://127.0.0.1:8000/?canisterId=rkp4c-7iaaa-aaaaa-aaaca-cai

1st working example :

public query func test1() : async Text{
	return "Hello";
};

°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
2nd working example:

°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°
Now, this doesnt work… (but if I add query keyword, as I should, it works)

But… If i deploy the code on Live icp, it works (even without query keyword), and it also works on the npm run dev interface localhost:5000 …

For the update method, without query, it seems to properly write data, but I got the error.
It seems possible to work but i don’t really like to have this in my terminal and I can’t know if it could make other errors later.

Don’t break your head too much for this, but in case you have a quick idea… I will be happy.

[peterparker]

I don’t have the reference from the doc right here and did not search through the forum but basically, to give you a really short answer, query calls cannot modify the state of the canisters, only update calls can.

It has to do with security, persistance etc. worth having a deeper look but just wanted to give you a short feedback.

[passio]

Thank you, yes, that’s why I mentionned the problem only occur with update methods…
It doesn’t explain why it works with localhost:5000 adress on in live on the mainet… … No problem, I’m finally going back to continue my project like this.

[peterparker]

Oh my bad, I misunderstand your question and skipped the error message.

So if I get it right, it does not work because of the error printed above Fail to verify certificate.

I think this happens often locally when the fetchRootKey is not called for local development. Do you do so?

agent.fetchRootKey().catch(err => {
      console.warn("Unable to fetch root key. Check to ensure that your local replica is running");
      console.error(err);
    });

where you create the actor is there?

[peterparker]

if your project is open source, I can quickly clone it and have a look if you want.

[passio]

I don’t use the fetchRootKey, I doesn’t really understand what is it and how to use.
I think I can work a little like this for now. If I spend another hour debugging, I’ll definitely give up everything. I’ll probably come back to this later and send you the project if needed. Thank you very much.

[peterparker]

fechtRootKey is needed for local development. when you want to call your local replica - started with dfx start - agent js will need to validate the certificate which is initialized with fechtRootKey

long story short, to develop locally - and locally only - fechtRootKey needs to be called

[passio]

Thank you ! I missed this part.