feat: Check transaction size

[howjmay]

In ProtocolConfig there are two more const will affect us. They are

• max_size_written_objects
• max_serialized_tx_effects_size_bytes

The problem is we can't know how many object we have written (mutated, created, unwrapped) during execution, because we dont know the size of AssetBag.
And the max_serialized_tx_effects_size_bytes regulates the size of Move execution result, which is impossible for us to get too.

[dessaya]

The returned error must be vmexceptions.ErrMaxTransactionSizeExceeded.

[dessaya]

Suggested change

	// checkTransactionSize panics with ErrMaxTransactionSizeExceeded if the estimated transaction size exceeds the limit
	// checkTransactionSize returns ErrMaxTransactionSizeExceeded if the estimated transaction size exceeds the limit

[dessaya]

These numbers are arbitrary?

[howjmay]

no they are values from iota repo

[howjmay]

The constants here come from struct ProtocolConfig in crates/iota-protocol-config/src/lib.rs

[dessaya]

There is a lot of stuff that is added to the PTB when BuildTransactionEssence is called. That is not being included here? In that case the estimation will be always lower than the real size.

Look at the stardast implementation:

wasp/packages/vm/vmimpl/runreq.go

Lines 514 to 521 in 06b7a38

	func (vmctx *vmContext) checkTransactionSize() error {
	essence, _ := vmctx.BuildTransactionEssence(state.L1CommitmentNil, false)
	tx := transaction.MakeAnchorTransaction(essence, &iotago.Ed25519Signature{})
	if tx.Size() > parameters.L1().MaxPayloadSize {
	return vmexceptions.ErrMaxTransactionSizeExceeded
	}
	return nil
	}

[howjmay]

I reformed the way to check the tx size. I build the tx every time the check func is called