ligo/lib_node_shell/distributed_db.mli

263 lines
8.5 KiB
OCaml

(**************************************************************************)
(* *)
(* Copyright (c) 2014 - 2017. *)
(* Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
(* *)
(* All rights reserved. No warranty, explicit or implicit, provided. *)
(* *)
(**************************************************************************)
(** Tezos Shell - High-level API for the Gossip network and local storage. *)
type t
type db = t
module Message = Distributed_db_message
module Metadata = Distributed_db_metadata
type p2p = (Message.t, Metadata.t) P2p.net
val create: State.t -> p2p -> t
val state: db -> State.t
val shutdown: t -> unit Lwt.t
(** {1 Network database} *)
(** An instance of the distributed DB for a given network (mainnet,
current testnet, ...) *)
type net_db
(** Activate a given network. The node will notify its neighbours that
it now handles the given network and that it expects notification
for new head or new operations. *)
val activate: t -> State.Net.t -> net_db
(** Look for the database of an active network. *)
val get_net: t -> Net_id.t -> net_db option
(** Deactivate a given network. The node will notify its neighbours
that it does not care anymore about this network. *)
val deactivate: net_db -> unit Lwt.t
type callback = {
notify_branch: P2p.Peer_id.t -> Block_locator.t -> unit ;
notify_head: P2p.Peer_id.t -> Block_header.t -> Mempool.t -> unit ;
disconnection: P2p.Peer_id.t -> unit ;
}
(** Register all the possible callback from the distributed DB to the
validator. *)
val set_callback: net_db -> callback -> unit
(** Kick a given peer. *)
val disconnect: net_db -> P2p.Peer_id.t -> unit Lwt.t
(** Various accessors. *)
val net_state: net_db -> State.Net.t
val db: net_db -> db
(** {1 Sending messages} *)
module Request : sig
(** Send to a given peer, or to all known active peers for the
network, a friendly request "Hey, what's your current branch
?". The expected answer is a `Block_locator.t.`. *)
val current_branch: net_db -> ?peer:P2p.Peer_id.t -> unit -> unit
(** Send to a given peer, or to all known active peers for the
given network, a friendly request "Hey, what's your current
branch ?". The expected answer is a `Block_locator.t.`. *)
val current_head: net_db -> ?peer:P2p.Peer_id.t -> unit -> unit
end
module Advertise : sig
(** Notify a given peer, or all known active peers for the
network, of a new head and possibly of new operations. *)
val current_head:
net_db -> ?peer:P2p.Peer_id.t ->
?mempool:Mempool.t -> State.Block.t -> unit
(** Notify a given peer, or all known active peers for the
network, of a new head and its sparse history. *)
val current_branch:
net_db -> ?peer:P2p.Peer_id.t ->
State.Block.t -> unit Lwt.t
end
(** {1 Indexes} *)
(** Generic interface for a "distributed" index.
By "distributed", it means that this interface abstract the p2p
gossip layer and it is able to fetch missing data from known
peers in a "synchronous" interface.
*)
module type DISTRIBUTED_DB = sig
type t
type key
(** The index key *)
type value
(** The indexed data *)
(** Is the value known locally? *)
val known: t -> key -> bool Lwt.t
type error += Missing_data of key
(** Return the value if it is known locally, otherwise fail with
the error [Missing_data]. *)
val read: t -> key -> value tzresult Lwt.t
(** Return the value if it is known locally, otherwise fail with
the value [None]. *)
val read_opt: t -> key -> value option Lwt.t
(** Return the value if it is known locally, otherwise fail with
the exception [Not_found]. *)
val read_exn: t -> key -> value Lwt.t
type param (** An extra parameter for the network lookup, usually
used for prevalidating data. *)
type error += Timeout of key
(** Return the value if it is known locally, or block until the data
is received from the network. By default, the data will be
requested to all the active peers in the network; if the [peer]
argument is provided, the data will only be requested to the
provided peer. By default, the resulting promise will block
forever if the data is never received. If [timeout] is provided
the promise will be resolved with the error [Timeout] after the
provided amount of seconds.
A internal scheduler is able to re-send the request with an
exponential back-off until the data is received. If the function
is called multiple time with the same key but with disctinct
peers, the internal scheduler randomly chooses the requested
peer (at each retry). *)
val fetch:
t ->
?peer:P2p.Peer_id.t ->
?timeout:float ->
key -> param -> value tzresult Lwt.t
(** Same as `fetch` but the call is non-blocking: the data will be
stored in the local index when received. *)
val prefetch:
t ->
?peer:P2p.Peer_id.t ->
?timeout:float ->
key -> param -> unit
type error += Canceled of key
(** Remove the data from the local index or cancel all pending
request. Any pending [fetch] promises are resolved with the
error [Canceled]. *)
val clear_or_cancel: t -> key -> unit
(** Monitor all the fetched data. A given data will appear only
once. *)
val watch: t -> (key * value) Lwt_stream.t * Lwt_watcher.stopper
end
(** {2 Block index} *)
(** Index of block headers. *)
module Block_header : sig
type t = Block_header.t (* avoid shadowing. *)
include DISTRIBUTED_DB with type t := net_db
and type key := Block_hash.t
and type value := Block_header.t
and type param := unit
end
(** Lookup for block header in any active networks *)
val read_block_header:
db -> Block_hash.t -> (Net_id.t * Block_header.t) option Lwt.t
(** Index of all the operations of a given block (per validation pass). *)
module Operations :
DISTRIBUTED_DB with type t := net_db
and type key = Block_hash.t * int
and type value = Operation.t list
and type param := Operation_list_list_hash.t
(** Index of all the hashes of operations of a given block (per
validation pass). *)
module Operation_hashes :
DISTRIBUTED_DB with type t := net_db
and type key = Block_hash.t * int
and type value = Operation_hash.t list
and type param := Operation_list_list_hash.t
(** Store on disk all the data associated to a valid block. *)
val commit_block:
net_db ->
Block_hash.t ->
Block_header.t -> Operation.t list list ->
Updater.validation_result ->
State.Block.t option tzresult Lwt.t
(** Store on disk all the data associated to an invalid block. *)
val commit_invalid_block:
net_db ->
Block_hash.t -> Block_header.t -> Error_monad.error list ->
bool tzresult Lwt.t
(** Monitor all the fetched block headers (for all activate networks). *)
val watch_block_header:
t -> (Block_hash.t * Block_header.t) Lwt_stream.t * Lwt_watcher.stopper
(** {2 Operations index} *)
(** Index of operations (for the mempool). *)
module Operation : sig
type t = Operation.t (* avoid shadowing. *)
include DISTRIBUTED_DB with type t := net_db
and type key := Operation_hash.t
and type value := Operation.t
and type param := unit
end
(** Inject a new operation in the local index (memory only). *)
val inject_operation:
net_db -> Operation_hash.t -> Operation.t -> bool tzresult Lwt.t
(** Monitor all the fetched operations (for all activate networks). *)
val watch_operation:
t -> (Operation_hash.t * Operation.t) Lwt_stream.t * Lwt_watcher.stopper
(** {2 Protocol index} *)
(** Index of protocol sources. *)
module Protocol : sig
type t = Protocol.t (* avoid shadowing. *)
include DISTRIBUTED_DB with type t := db
and type key := Protocol_hash.t
and type value := Protocol.t
and type param := unit
end
(** Store on disk protocol sources. *)
val commit_protocol:
db -> Protocol_hash.t -> Protocol.t -> bool tzresult Lwt.t
(**/**)
module Raw : sig
val encoding: Message.t P2p.Raw.t Data_encoding.t
val supported_versions: P2p_types.Version.t list
end