This patch is co-authored with: cagdas.bozman@ocamlpro.com
With this patch the economic protocol is now compiled as as
"functor-pack", parameterized over the environment. This will ease the
protocol reusability outside of the tezos source tree (e.g. for a
michelson Web IDE) and will allow proper unit testing of the economic
protocol.
This functorization allows to break the dependency of the
'tezos-protocol-compiler' on various '.mli' of the node, and hence
we don't need anymore the unusual compilation schema:
a.mli -> b.mli -> b.ml -> a.ml
where 'A' is linked after 'B' but 'a.mli' should still be compiled
before 'b.mli'. This will simplify a switch to 'ocp-build' or 'jbuiler'.
Operations now include a block hash in their header. Such an operation
could only be included in a successor of this block.
Furthermore, when validating a block, the economic protocol now
returns---together with the context---an integer `max_operations_ttl`.
Then, when validating a successor, the shell will fail if it contains
an operation whose header's block hash is not one the
`max_operations_ttl` predecessors of the block.
As a bonus, the shell is now able to detect and forbid replayed
operations. Then, we might decide to remove some replay
detection-mechanism that we previously implemented in the economic
protocol.
It now takes a `proto_header` in parameter, and it returns a full
`shell_header`. This prepares the inclusion of the context's hash in the
`shell_header`.
Let's get serious. The full index of operations is not sustainable in
the production code. We now only keep the index of operations not yet
in the chain (i.e. the mempool/prevalidation). Operations from the
chain are now only accesible through a block. For instance, see the
RPC:
/blocks/<hash>/proto/operations
This prepares the context to the inclusion the hash of the context in
the block header. By "looking" into the resulting context of a block,
we are now know able to determine whether:
- no testnet is currently associated to the branch;
- a testnet must be forked after the block;
- a previously forked testnet is running.
The minimal header now (classically) contains the root of a Merkle tree,
wrapping a list of lists of operations. Currently, the validator only
accept a single list of operations, but the 3+pass validator will
requires at least two lists.
It wait for the node to be synchronized with the network. The heuristic
is currently:
- the timestamp of current head is less than 1 minute old ;
- there was a period of 30 seconds without new block discovered.
Intead of providing a `fitness` function, an economic protocol should
now call `Context.set_fitness`.
This simplify the shell's code and avoid complexity on protocol
change. Previously the fitness of a context produced by the old protocol
had to be read by the new protocol. Now, the shell read the context
without requesting the help of the economic protocol.
This refactors `src/node/shell/state.ml` in order to trace the source of
blocks and operations. This prepares the node for the three-pass
validator.
In the procces, it adds an in-memory overlay for blocks and operations.
