Networking or low-level protocol error: Failed to load system certs: No valid certificate found

[buraktabn]

I'm using subxt to send transactions via RPC. It builds and passes the test. However, when I try to call this method from Flutter, I get an exception.

Since, the test passes (not throwing an error for certificate), I assume the issue is related to the flutter bridge. What could be the reason for this exception?

#[tokio::main(flavor = "current_thread")]
pub async fn create_xt() -> anyhow::Result<Vec<u8>> {
    let client = ClientBuilder::new()
        .set_url("wss://ecample.com:9922")
        .build::<DefaultConfig>()
        .await?;

    let profile_api = TransactionApi::<
        _,
        SubstrateExtrinsicParams<DefaultConfig>,
    >::new(&client);

    let be_pro = profile_api.become_pro(Profession::CommercialAppraiser, None)?;
    let signer = subxt::PairSigner::new(AccountKeyring::Alice.pair());


    Ok(be_pro.create_signed(&signer, Default::default()).await?.0)
}

#[cfg(test)]
mod tests {
    use crate::client::create_xt;

    #[test]
    fn it_works() {
        tokio_test::block_on(async {
            let xt = create_xt().await;

            assert!(xt.is_ok());
        })
    }
}

I/flutter (12850): FfiException(RESULT_ERROR, Rpc error: Networking or low-level protocol error: Failed to load system certs: No valid certificate found
I/flutter (12850): 
I/flutter (12850): Caused by:
I/flutter (12850):     0: Networking or low-level protocol error: Failed to load system certs: No valid certificate found
I/flutter (12850):     1: Failed to load system certs: No valid certificate found, null)
I/flutter (12850): #0      FlutterRustBridgeBase._transformRust2DartMessage (package:flutter_rust_bridge/src/basic.dart:89:9)
I/flutter (12850): #1      FlutterRustBridgeBase.executeNormal.<anonymous closure> (package:flutter_rust_bridge/src/basic.dart:45:9)
I/flutter (12850): #2      _rootRunUnary (dart:async/zone.dart:1434:47)
I/flutter (12850): #3      _CustomZone.runUnary (dart:async/zone.dart:1335:19)
I/flutter (12850): <asynchronous suspension>
I/flutter (12850): #4      Realm3Client.createXt (package:realm3_client/src/api.dart:23:17)
I/flutter (12850): <asynchronous suspension>
I/flutter (12850): FfiException(RESULT_ERROR, Rpc error: Networking or low-level protocol error: Failed to load system certs: No valid certificate found

[fzyzcjy]

No, I suspect it is not related to bridge, but related to your running environment. For example, a ios simulator is different from flutter's widget test env.

[buraktabn]

I don't think it's related to bridge now. It works fine on localhost. I think it's looking for a certificate somewhere in the system but it can't access what dart can access.

[justinmoon]

Did you ever find out what was causing this? I'm seeing this trying to connect to secure websocket connection (wss://...). It only happens on android ...

[buraktabn]

Solved here paritytech/subxt#563 (comment)

[justinmoon]

Thanks