How to create a Polkadot chain spec for development purposes?

Question

I want to setup my own custom Relay chain for development purposes.

Is there a way to generate a local chain spec for Polkadot (Rococo) something like this:

./target/release/polkadot build-spec --disable-default-bootnode --chain local > localCustomSpec.json
Error:
   0: Invalid input: Error opening spec file `local`: No such file or directory (os error 2)

If I do this:

./target/release/polkadot build-spec --disable-default-bootnode --chain rococo-local > rococoLocalCustomSpec.json

It gives me all the dev keys i.e. Alice, Bob, etc configured in the chain spec.

I want it with no keys so I can add my own custom keys.

Answer 1

You can remove those keys in customSpec.json but it will still show in polkadot-js explorer.

You need to remove it in the chain_spec.rs you can find it here:

• https://github.com/paritytech/polkadot/blob/a6cfdb16e9a69259ee824fa0aa60c36e4c63f3fa/node/service/src/chain_spec.rs#L1897-L1917