Canister does not consume cycles (local)

Developers
21

is it really internal, though? This looks like a normal candid wrapper, exposing it as an external method:

22

I rather see a problem here, in that only the governance canister may call the method:

I would change that line in prod to also allow the controller to call the method. That is secure in prod, I think, and it would allow developers to call it if they deploy a CMC canister themselves. For this particular case I would just comment out the check and rebuild the CMC canister, if that is OK, @rabbithole . Great handle, by the way, especially when asking questions that take us down rabbit holes! :smiley:

Alternatively you could deploy the CMC canister specifying yourself as the governance canister. Avoids recompiling. But seems somehow wrong. Let’s just whitelist controllers and be done with it.

2 Likes
23

I am sorry, I am out of time for now. Please try to get this to work and if it still doesn’t work, please ping back and I/we can have another look when we get the chance. I’m disappointed to have got only part of the way through the puzzle.

1 Like
24

It would be great to get a custom cmc.wasm to work in a local environment, after all, internet identity also has a build for developers.

I’m trying to build cmc.wasm, I can come back with the result later, thank you very much!

1 Like
25

One more question - how can I find out the subnet id that is deployed on my computer? The get_subnet_types_to_subnets method returns an empty array.

26

The subnet ID is the same as the root key, for local dfx. In Rust I wrote the conversion as:

/// Gets the subnet ID
#[context("Failed to determine subnet ID.")]
async fn get_subnet_id(agent: &Agent) -> anyhow::Result<Principal> {
    let root_key = agent
        .status()
        .await
        .with_context(|| "Could not get agent status")?
        .root_key
        .with_context(|| "Agent should have fetched the root key.")?;
    Ok(Principal::self_authenticating(root_key))
}
1 Like
27

Since I am not very familiar with the Rust language, I wrote a node script to get subnet_id:

import { Principal } from '@dfinity/principal';
import { getLocalHttpAgent } from './utils/agent.utils.mjs';

async function getSubnetId() {
    const agent = await getLocalHttpAgent();
    const status = await agent.status();
    return Principal.selfAuthenticating(status.root_key).toText();
}

const subnetId = await getSubnetId();
console.log(subnetId);

I received a suspiciously long value:

jz726-l5fnc-4y635-dnhxc-fugxd-snmg6-q455t-h4zlv-2bqrn-qijin-hqe

I hope there is still no error…

1 Like
28

Снимок экрана 2023-09-14 в 19.47.19
Снимок экрана 2023-09-14 в 19.47.192012×420 48.8 KB

It seems that I’m getting the subnet_id incorrectly :thinking:

29

I am not too familiar with the JS API but hopefully we can find the problem. :slight_smile: Just by the name, though, I guess that the JS is taking the raw bytes. Principal::self_authenticating(X) is sha224(x) (28 bytes) followed by the byte “2” to yield 29 bytes in total: https://github.com/dfinity/candid/blob/a1eb218c4777d7a1be263f061d499dfc428136a2/rust/candid/src/types/principal.rs#L122

2 Likes
30

Nice! I found a similar method in @dfinity/principal lib, now I get a short subnet_id:

Principal.selfAuthenticating(status.root_key).toText()

I was able to apply the settings for CMC! The canister is now created! Many thanks to everyone who tried to help and special thanks @bitdivine, later I will add all the code examples to the repository and edit this message.

Update: I pushed the changes to the project repository with a small readme for developers. I hope this will be useful to someone.

5 Likes