frontier template upgrade to polkadotv0.9.38 but using Babe instead of Aura

Question

I've upgraded the frontier-node-template to substrate polkadot-v0.9.38, I've fixed all issues in runtime, migrated my code as well. But since last few days, I'm stuck in converting service.rs file in node folder from aura to Babe. I'm new to Rust and substrate therefore, having problems in trait implementations, get lot's of trait bound errors using BabeLink.

I've referred to the substrate branches' available which implement Babe but those some how are not compatible with my frontier code.

Any help will be appreciated, I will share my service.rs file if required please?

Answer 1

This is not an easy question to answer for multiple reasons. My suggestion is to first go through the other multiple answers on here on how the aura -> babe transition goes. You're correct that this requires you to make changes to the import_queue and the block_import, in the service.rs file, make changes to the rpc.rs file to include BabeDeps and BabeRpcHandler like so :

    io.extend_with(sc_consensus_babe_rpc::BabeApi::to_delegate(BabeRpcHandler::new(
        client.clone(),
        shared_epoch_changes.clone(),
        keystore,
        babe_config,
        select_chain,
        deny_unsafe,
    )));
    io.extend_with(sc_finality_grandpa_rpc::GrandpaApi::to_delegate(GrandpaRpcHandler::new(
        shared_authority_set.clone(),
        shared_voter_state,
        justification_stream,
        subscription_executor,
        finality_provider,
    )));

besides having the necessary pallets in the runtime. Also you need to make the adjustments in the GenesisConfig struct in your chain_spec.rs.

To get a better feel for this, I would suggest migrating a vanilla substrate-node-template to use babe. This would give you enough experience to know what exact changes are needed to be made. Then you may do the same with the frontier template as it's almost exactly like the substrate-node-template except it has frontier integrated into it, and not such a straightforward directory structure as one you'd find on the node-template.

If you're still stuck after doing all this which is unlikely, then I just editing your question to include a repository link where someone might be able to take a look at what you're doing wrong. But I highly recommend trying to troubleshoot it yourself first.