Get rid off parachain-info

[bkchr]

I added this pallet back in the old days to have an easy way to configure the ParaId. However, nowadays we don't support to change the ParaId via the CLI, but the crate stayed and is used by everyone... The only thing the crate is doing is to provide a Get<ParaId> which can also just be created by parameter_types! (at compile time).

We should start removing the crate from all of our runtimes and explain better for what the pallet is/should be used for. Then we should tag it as deprecated and remove it at some point. If someone wants to continue using it, they can just copy it or may switch to the new parameter pallet (which does the same job, but in a generic way).

[philoniare]

@bkchr can you assign this to me?

[xlc]

parachain-info is the only way to fetch parachain id from a runtime. we cannot remove it without a replacement mechanism

[xlc]

The replacement mechanism #3517

We need a proper deprecation process for this including provide migrations to remove the storage and an entry in release note

[philoniare]

@xlc okay got it, I'll wait for #3517 to be merged then

[philoniare]

@xlc looks like #3517 got merged. Would really appreciate some pointers on the migrations that need to be done after removing parachain-info from cumulus pallets. Is there any similar migration performed before? Would I need to add migrations to delete the paraId on all of the runtimes in cumulus/parachains/runtimes like this?

frame_support::storage::unhashed::kill(
        &<ParachainInfo as PalletInfoAccess>::name(),
        &[module.as_bytes(), b"ParachainId"],
    );

[ggwpez]

Pallets can be deleted with RemovePallet, since its just one value that should be fine.

[philoniare]

Pallets can be deleted with RemovePallet, since its just one value that should be fine.

Ah great, thanks for pointing it out 🙏

[philoniare]

unassigning myself as this seems like a trivial refactor for beginners