test validator write stake account to JSON

[buffalojoec]

Problem

The test validator writes its validator identity and vote account to JSON files on startup, but it doesn't do this for its stake account.

Summary of Changes

Write the stake account to JSON on startup.

[steviez]

Not that it is necessarily a problem, but curious about the motivation for this. A real validator has identity and vote account key pairs, and any stake accounts would be either:

• A stake account owned by operator whose key shouldn't exist on same machine for sake of operational security OR
• A stake account owned by a delegator whose key definitely doesn't on the machine

[buffalojoec]

Not that it is necessarily a problem, but curious about the motivation for this. A real validator has identity and vote account key pairs, and any stake accounts would be either:

• A stake account owned by operator whose key shouldn't exist on same machine for sake of operational security OR
• A stake account owned by a delegator whose key definitely doesn't on the machine

That's fair but in the case of a test validator I think it makes sense to be able to access any and all keypairs that operate the machine - that you as the node operator would otherwise be in control of in some fashion.

Specifically, in Web3 JS land, we are looking for the keypair (or even an emitted pubkey) to test our RPC API
https://github.com/buffalojoec/solana-web3.js/blob/account-fixtures-in-tests/packages/rpc-core/src/rpc-methods/__tests__/get-program-accounts-test.ts#L17
https://github.com/buffalojoec/solana-web3.js/blob/account-fixtures-in-tests/packages/rpc-core/src/rpc-methods/__tests__/get-program-accounts-test.ts#L898

[steviez]

Specifically, in Web3 JS land, we are looking for the keypair (or even an emitted pubkey) to test our RPC API

👍