* Add light client TODO item

* Move existing total-difficulty-based fork choice check to Engine

* Abstract total difficulty and block provider as Machine::BlockMetadata and Machine::BlockProvider

* Decouple "generate_metadata" logic to Engine

* Use fixed BlockMetadata and BlockProvider type for null and instantseal

In this way they can use total difficulty fork choice check

* Extend blockdetails with metadatas and finalized info

* Extra data update: mark_finalized and update_metadatas

* Check finalized block in Blockchain

* Fix a test constructor in verification mod

* Add total difficulty trait

* Fix type import

* Db migration to V13 with metadata column

* Address grumbles

* metadatas -> metadata

* Use generic type for update_metadata to avoid passing HashMap all around

* Remove metadata in blockdetails

* [WIP] Implement a generic metadata architecture

* [WIP] Metadata insertion logic in BlockChain

* typo: Value -> Self::Value

* [WIP] Temporarily remove Engine::is_new_best interface

So that we don't have too many type errors.

* [WIP] Fix more type errors

* [WIP] ExtendedHeader::PartialEq

* [WIP] Change metadata type Option<Vec<u8>> to Vec<u8>

* [WIP] Remove Metadata Error

* [WIP] Clean up error conversion

* [WIP] finalized -> is_finalized

* [WIP] Mark all fields in ExtrasInsert as pub

* [WIP] Remove unused import

* [WIP] Keep only local metadata info

* Mark metadata as optional

* [WIP] Revert metadata db change in BlockChain

* [WIP] Put finalization in unclosed state

* Use metadata interface in BlockDetail

* [WIP] Fix current build failures

* [WIP] Remove unused blockmetadata struct

* Remove DB migration info

* [WIP] Typo

* Use ExtendedHeader to implement fork choice check

* Implement is_new_best using Ancestry iterator

* Use expect instead of panic

* [WIP] Add ancestry Engine support via on_new_block

* Fix tests

* Emission of ancestry actions

* use_short_version should take account of metadata

* Engine::is_new_best -> Engine::fork_choice

* Use proper expect format as defined in #1026

* panic -> expect

* ancestry_header -> ancestry_with_metadata

* Boxed iterator -> &mut iterator

* Fix tests

* is_new_best -> primitive_fork_choice

* Document how fork_choice works

* Engine::fork_choice -> Engine::primitive_fork_choice

* comment: clarify types of finalization where Engine::primitive_fork_choice works

* Expose FinalizationInfo to Engine

* Fix tests due to merging

* Remove TotalDifficulty trait

* Do not pass FinalizationInfo to Engine

If there's finalized blocks in from route, choose the old branch without calling `Engine::fork_choice`.

* Fix compile

* Fix unused import

* Remove is_to_route_finalized

When no block reorg passes a finalized block, this variable is always false.

* Address format grumbles

* Fix docs: mark_finalized returns None if block hash is not found

`blockchain` mod does not yet have an Error type, so we still temporarily use None here.

* Fix inaccurate tree_route None expect description

asynchronous rob authored Jun 28, 2017 and Arkadiy Paronyan committed Jun 28, 2017

* final engine changes

* migration to v13

* adding and removing pending transitions

* epoch_transition_for

* port snapshot to new engine methods

* final validator set interface

* fix compiler errors

* revert v13/epoch_depth transition

* make call on new epoch

* rolling finality checker

* tests for finality checker

* constructing finality proof upon pending transition

* fix warnings and finality proof checking

* fix compiler warnings in tests

* test fixes

* don't include genesis in finality checking

* change snapshot test chain building logic

* minor refactorings

* fetch epoch transition based on parent, fix divide-by-zero in SimpleList

* fix formatting

* fix ABIs and finality checking in snapshot restoration

* encode signal number in proof

* create more blocks at the end of tests

* update gist to accurate contract code

* test for epoch_transition_for

* fix tests with immediateTransitions parameter

* disable force flag after forcing

* rename ValidatorsChanged to InitiateChange and finalizeSignal to finalizeChange

* a few more validator set tests

* Fix whitespace.

* Update copyright years/owner.

* Push release only for tags.

- Move Updater into its own crate.
- Change ethcore -> parity in authors, homepages and licenses.

* to_rlp takes self by-reference

* clean up some derefs

* out-of-order insertion for blockchain

* implement block rebuilder without verification

* group block chunk header into struct

* block rebuilder does verification

* integrate snapshot service with client service; flesh out implementation more

* initial implementation of snapshot service

* remove snapshottaker trait

* snapshot writer trait with packed and loose implementations

* write chunks using "snapshotwriter" in service

* have snapshot taking use snapshotwriter

* implement snapshot readers

* back up client dbs when replacing

* use snapshot reader in snapshot service

* describe offset format

* use new get_db_path in parity, allow some errors in service

* blockchain formatting

* implement parity snapshot

* implement snapshot restore

* force blocks to be submitted in order

* fix bug loading block hashes in packed reader

* fix seal field loading

* fix uncle hash computation

* fix a few bugs

* store genesis state in db. reverse block chunk order in packed writer

* allow out-of-order import for blocks

* bring restoration types together

* only snapshot the last 30000 blocks

* restore into overlaydb instead of journaldb

* commit version to database

* use memorydbs and commit directly

* fix trie test compilation

* fix failing tests

* sha3_null_rlp, not H256::zero

* move overlaydb to ref_overlaydb, add new overlaydb without on-disk rc

* port archivedb to new overlaydb

* add deletion mode tests for overlaydb

* use new overlaydb, check state root at end

* share chain info between state and block snapshotting

* create blocks snapshot using blockchain directly

* allow snapshot from arbitrary block, remove panickers from snapshot creation

* begin test framework

* blockchain chunking test

* implement stateproducer::tick

* state snapshot test

* create block and state chunks concurrently, better restoration informant

* fix tests

* add deletion mode tests for overlaydb

* address comments

* more tests

* Fix up tests.

* remove a few printlns

* add a little more documentation to `commit`

* fix tests

* fix ref_overlaydb test names

* snapshot command skeleton

* revert ref_overlaydb renaming

* reimplement snapshot commands

* fix many errors

* everything but inject

* get ethcore compiling

* get snapshot tests passing again

* instrument snapshot commands again

* fix fallout from other changes, mark snapshots as experimental

* optimize injection patterns

* do two injections

* fix up tests

* take snapshots from 1000 blocks efore

* address minor comments

* fix a few io crate related errors

* clarify names about total difficulty

[ci skip]

* use bloomchain crate in blockchain module. remove obsole chainfilter submodule

* update database version to 6.0

* removed redundant line

* simple db migration

* make migration slightly more functional

* bloomchain migration

* migration version is just a single unsigned integer

* updated migration v6

* parity migration

* db migration

* removed hardcoded migration dir

* replace ptr::copy with clone_from_slice, removed potential endianess problem from trace/db.rs

* removed superfluous line

* blockchains log blooms config is not exposed any more

Moving all Client public API types to separate mod & binary serialization codegen for that mod (#1051)

* transaction moved

* trash remove

* ids move

* receipt

* tree-route

* blockchain info

* log_entry move

* trace filter moved

* executed & trace moved

* localized trace moved

* block status moved

* build scripts and codegen refs

* Cargo.lock update

* binary for blockstatus, blockchaininfo

* binary for trace

* trace filters binary ser

* binary for log entries & executed

* binary for receipt

* special case for u8 & transaction binary attribute

* resolved remaining issues & error binary serialization

* json-tests util import

* fix warnings

* ids attr

* add missing attributes

* Update build.rs