%%% -*- erlang -*- %% %% Copyright (c) 2012-2015 Rakuten, Inc. %% Copyright (c) 2016 Benoit Chesneau %% %% Licensed under the Apache License, Version 2.0 (the "License"); %% you may not use this file except in compliance with the License. %% You may obtain a copy of the License at %% %% http://www.apache.org/licenses/LICENSE-2.0 %% %% Unless required by applicable law or agreed to in writing, software %% distributed under the License is distributed on an "AS IS" BASIS, %% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. %% See the License for the specific language governing permissions and %% limitations under the License. %% @doc Erlang Wrapper for RocksDB -module(rocksdb). -export([open/2, open_with_cf/3, close/1]). -export([snapshot/1, release_snapshot/1]). -export([list_column_families/2, create_column_family/3, drop_column_family/1]). -export([put/4, put/5, delete/3, delete/4, write/3, get/3, get/4]). -export([iterator/2, iterator/3, iterators/3, iterators/4, iterator_move/2, iterator_close/1]). -export([fold/4, fold/5, fold_keys/4, fold_keys/5]). -export([destroy/2, repair/2, is_empty/1]). -export([checkpoint/2]). -export([count/1, count/2, stats/1, stats/2, get_property/2, get_property/3]). -export_type([db_handle/0, cf_handle/0, itr_handle/0, snapshot_handle/0, compression_type/0, compaction_style/0, access_hint/0, wal_recovery_mode/0]). -on_load(init/0). %% This cannot be a separate function. Code must be inline to trigger %% Erlang compiler's use of optimized selective receive. -define(WAIT_FOR_REPLY(Ref), receive {Ref, Reply} -> Reply end). -spec init() -> ok | {error, any()}. init() -> SoName = case code:priv_dir(?MODULE) of {error, bad_name} -> case code:which(?MODULE) of Filename when is_list(Filename) -> filename:join([filename:dirname(Filename),"../priv", "rocksdb"]); _ -> filename:join("../priv", "rocksdb") end; Dir -> filename:join(Dir, "rocksdb") end, erlang:load_nif(SoName, application:get_all_env(rocksdb)). -record(db_path, {path :: file:filename_all(), target_size :: non_neg_integer()}). -record(cf_descriptor, {name :: string(), options :: cf_options()}). -type compression_type() :: snappy | zlib | bzip2 | lz4 | lz4h | none. -type compaction_style() :: level | universal | fifo | none. -type access_hint() :: normal | sequential | willneed | none. -type wal_recovery_mode() :: tolerate_corrupted_tail_records | absolute_consistency | point_in_time_recovery | skip_any_corrupted_records. -opaque db_handle() :: binary(). -opaque cf_handle() :: binary(). -opaque itr_handle() :: binary(). -opaque snapshot_handle() :: binary(). -type block_based_table_options() :: [{no_block_cache, boolean()} | {block_size, pos_integer()} | {block_cache_size, pos_integer()} | {bloom_filter_policy, BitsPerKey :: pos_integer()} | {format_version, 0 | 1 | 2} | {skip_table_builder_flush, boolean()} | {cache_index_and_filter_blocks, boolean()}]. -type cf_options() :: [{block_cache_size_mb_for_point_lookup, non_neg_integer()} | {memtable_memory_budget, pos_integer()} | {write_buffer_size, pos_integer()} | {max_write_buffer_number, pos_integer()} | {min_write_buffer_number_to_merge, pos_integer()} | {compression, compression_type()} | {num_levels, pos_integer()} | {level0_file_num_compaction_trigger, integer()} | {level0_slowdown_writes_trigger, integer()} | {level0_stop_writes_trigger, integer()} | {max_mem_compaction_level, pos_integer()} | {target_file_size_base, pos_integer()} | {target_file_size_multiplier, pos_integer()} | {max_bytes_for_level_base, pos_integer()} | {max_bytes_for_level_multiplier, pos_integer()} | {max_compaction_bytes, pos_integer()} | {soft_rate_limit, float()} | {hard_rate_limit, float()} | {arena_block_size, integer()} | {disable_auto_compactions, boolean()} | {purge_redundant_kvs_while_flush, boolean()} | {compaction_style, compaction_style()} | {verify_checksums_in_compaction, boolean()} | {filter_deletes, boolean()} | {max_sequential_skip_in_iterations, pos_integer()} | {inplace_update_support, boolean()} | {inplace_update_num_locks, pos_integer()} | {table_factory_block_cache_size, pos_integer()} | {in_memory_mode, boolean()} | {block_based_table_options, block_based_table_options()}]. -type db_options() :: [{total_threads, pos_integer()} | {create_if_missing, boolean()} | {create_missing_column_families, boolean()} | {error_if_exists, boolean()} | {paranoid_checks, boolean()} | {max_open_files, integer()} | {max_total_wal_size, non_neg_integer()} | {disable_data_sync, boolean()} | {use_fsync, boolean()} | {db_paths, list(#db_path{})} | {db_log_dir, file:filename_all()} | {wal_dir, file:filename_all()} | {delete_obsolete_files_period_micros, pos_integer()} | {max_background_compactions, pos_integer()} | {max_background_flushes, pos_integer()} | {max_log_file_size, non_neg_integer()} | {log_file_time_to_roll, non_neg_integer()} | {keep_log_file_num, pos_integer()} | {max_manifest_file_size, pos_integer()} | {table_cache_numshardbits, pos_integer()} | {wal_ttl_seconds, non_neg_integer()} | {wal_size_limit_mb, non_neg_integer()} | {manifest_preallocation_size, pos_integer()} | {allow_os_buffer, boolean()} | {allow_mmap_reads, boolean()} | {allow_mmap_writes, boolean()} | {is_fd_close_on_exec, boolean()} | {skip_log_error_on_recovery, boolean()} | {stats_dump_period_sec, non_neg_integer()} | {advise_random_on_open, boolean()} | {access_hint, access_hint()} | {compaction_readahead_size, non_neg_integer()} | {use_adaptive_mutex, boolean()} | {bytes_per_sync, non_neg_integer()} | {skip_stats_update_on_db_open, boolean()} | {wal_recovery_mode, wal_recovery_mode()} | {allow_concurrent_memtable_write, boolean()} | {enable_write_thread_adaptive_yield, boolean()} | {in_memory, boolean()}]. -type read_options() :: [{verify_checksums, boolean()} | {fill_cache, boolean()} | {iterate_upper_bound, binary()} | {tailing, boolean()} | {total_order_seek, boolean()} | {snapshot, snapshot_handle()}]. -type write_options() :: [{sync, boolean()} | {disable_wal, boolean()} | {timeout_hint_us, non_neg_integer()} | {ignore_missing_column_families, boolean()}]. -type write_actions() :: [{put, Key::binary(), Value::binary()} | {put, ColumnFamilyHandle::cf_handle(), Key::binary(), Value::binary()} | {delete, Key::binary()} | {delete, ColumnFamilyHandle::cf_handle(), Key::binary()} | clear]. -type iterator_action() :: first | last | next | prev | binary(). %% @doc Open RocksDB with the defalut column family -spec open(Name, DBOpts) -> Result when Name :: file:filename_all(), DBOpts :: db_options(), Result :: {ok, db_handle()} | {error, any()}. open(Name, DBOpts) -> CallerRef = make_ref(), async_open(CallerRef, Name, DBOpts), ?WAIT_FOR_REPLY(CallerRef). async_open(_CallerRef, _Name, _DBOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Open RocksDB with the specified column families -spec(open_with_cf(Name, DBOpts, CFDescriptors) -> {ok, db_handle(), list(cf_handle())} | {error, any()} when Name::file:filename_all(), DBOpts :: db_options(), CFDescriptors :: list(#cf_descriptor{})). open_with_cf(Name, DBOpts, CFDescriptors) -> CallerRef = make_ref(), async_open_with_cf(CallerRef, Name, DBOpts, CFDescriptors), ?WAIT_FOR_REPLY(CallerRef). async_open_with_cf(_Callerfef, _Name, _DBOpts, _CFDescriptors) -> erlang:nif_error({error, not_loaded}). %% @doc Close RocksDB -spec close(DBHandle) -> Res when DBHandle :: db_handle(), Res :: ok | {error, any()}. close(DBHandle) -> CallerRef = make_ref(), async_close(CallerRef, DBHandle), ?WAIT_FOR_REPLY(CallerRef). async_close(_Callerfef, _DBHandle) -> erlang:nif_error({error, not_loaded}). %% =============================================== %% Column Families API %% =============================================== %% @doc List column families -spec list_column_families(Name, DBOpts) -> Res when Name::file:filename_all(), DBOpts::db_options(), Res :: {ok, list(string())} | {error, any()}. list_column_families(Name, DbOpts) -> CallerRef = make_ref(), async_list_column_families(CallerRef, Name, DbOpts), ?WAIT_FOR_REPLY(CallerRef). async_list_column_families(_Callerfef, _Name, _DbOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Create a new column family -spec create_column_family(DBHandle, Name, CFOpts) -> Res when DBHandle :: db_handle(), Name ::string(), CFOpts :: cf_options(), Res :: {ok, cf_handle()} | {error, any()}. create_column_family(DBHandle, Name, CFOpts) -> CallerRef = make_ref(), async_create_column_family(CallerRef, DBHandle, Name, CFOpts), ?WAIT_FOR_REPLY(CallerRef). async_create_column_family(_Callerfef, _DBHandle, _Name, _CFOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Drop a column family -spec drop_column_family(CFHandle) -> Res when CFHandle::cf_handle(), Res :: ok | {error, any()}. drop_column_family(CFHandle) -> CallerRef = make_ref(), async_drop_column_family(CallerRef, CFHandle), ?WAIT_FOR_REPLY(CallerRef). async_drop_column_family(_Callerfef, _CFHandle) -> erlang:nif_error({error, not_loaded}). %% @doc return a database snapshot %% Snapshots provide consistent read-only views over the entire state of the key-value store -spec snapshot(DbHandle::db_handle()) -> {ok, snapshot_handle()} | {error, any()}. snapshot(DbHandle) -> CallerRef = make_ref(), async_snapshot(CallerRef, DbHandle), ?WAIT_FOR_REPLY(CallerRef). async_snapshot(_CallerRef, _DbHandle) -> erlang:nif_error({error, not_loaded}). %% @doc release a snapshot -spec release_snapshot(SnapshotHandle::snapshot_handle()) -> ok | {error, any()}. release_snapshot(SnapshotHandle) -> CallerRef = make_ref(), async_release_snapshot(CallerRef, SnapshotHandle), ?WAIT_FOR_REPLY(CallerRef). async_release_snapshot(_CallerRef, _SnapshotHandle) -> erlang:nif_error({error, not_loaded}). %% @doc Put a key/value pair into the default column family -spec put(DBHandle, Key, Value, WriteOpts) -> Res when DBHandle::db_handle(), Key::binary(), Value::binary(), WriteOpts::write_options(), Res :: ok | {error, any()}. put(DBHandle, Key, Value, WriteOpts) -> write(DBHandle, [{put, Key, Value}], WriteOpts). %% @doc Put a key/value pair into the specified column family -spec put(DBHandle, CFHandle, Key, Value, WriteOpts) -> Res when DBHandle::db_handle(), CFHandle::cf_handle(), Key::binary(), Value::binary(), WriteOpts::write_options(), Res :: ok | {error, any()}. put(DBHandle, CFHandle, Key, Value, WriteOpts) -> write(DBHandle, [{put, CFHandle, Key, Value}], WriteOpts). %% @doc Delete a key/value pair in the default column family -spec(delete(DBHandle, Key, WriteOpts) -> ok | {error, any()} when DBHandle::db_handle(), Key::binary(), WriteOpts::write_options()). delete(DBHandle, Key, WriteOpts) -> write(DBHandle, [{delete, Key}], WriteOpts). %% @doc Delete a key/value pair in the specified column family -spec delete(DBHandle, CFHandle, Key, WriteOpts) -> Res when DBHandle::db_handle(), CFHandle::cf_handle(), Key::binary(), WriteOpts::write_options(), Res :: ok | {error, any()}. delete(DBHandle, CFHandle, Key, WriteOpts) -> write(DBHandle, [{delete, CFHandle, Key}], WriteOpts). async_write(_CallerRef, _DBHandle, _WriteActions, _WriteOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Apply the specified updates to the database. -spec write(DBHandle, WriteActions, WriteOpts) -> Res when DBHandle::db_handle(), WriteActions::write_actions(), WriteOpts::write_options(), Res :: ok | {error, any()}. write(DBHandle, WriteActions, WriteOpts) -> CallerRef = make_ref(), async_write(CallerRef, DBHandle, WriteActions, WriteOpts), ?WAIT_FOR_REPLY(CallerRef). %% @doc Retrieve a key/value pair in the default column family -spec get(DBHandle, Key, ReadOpts) -> Res when DBHandle::db_handle(), Key::binary(), ReadOpts::read_options(), Res :: {ok, binary()} | not_found | {error, any()}. get(DBHandle, Key, ReadOpts) -> CallerRef = make_ref(), async_get(CallerRef, DBHandle, Key, ReadOpts), ?WAIT_FOR_REPLY(CallerRef). async_get(_CallerRef, _DBHandle, _Key, _ReadOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Retrieve a key/value pair in the specified column family -spec get(DBHandle, CFHandle, Key, ReadOpts) -> Res when DBHandle::db_handle(), CFHandle::cf_handle(), Key::binary(), ReadOpts::read_options(), Res :: {ok, binary()} | not_found | {error, any()}. get(DBHandle, CFHandle, Key, ReadOpts) -> CallerRef = make_ref(), async_get(CallerRef, DBHandle, CFHandle, Key, ReadOpts), ?WAIT_FOR_REPLY(CallerRef). async_get(_CallerRef, _DBHandle, _CfHandle, _Key, _ReadOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Return a iterator over the contents of the database. %% The result of iterator() is initially invalid (caller must %% call iterator_move function on the iterator before using it). -spec iterator(DBHandle, ReadOpts) -> Res when DBHandle::db_handle(), ReadOpts::read_options(), Res :: {ok, itr_handle()} | {error, any()}. iterator(DBHandle, ReadOpts) -> CallerRef = make_ref(), async_iterator(CallerRef, DBHandle, ReadOpts), ?WAIT_FOR_REPLY(CallerRef). async_iterator(_CallerRef, _DBHandle, _ReadOpts) -> erlang:nif_error({error, not_loaded}). -spec iterator(DBHandle, ReadOpts, keys_only) -> Res when DBHandle::db_handle(), ReadOpts::read_options(), Res :: {ok, itr_handle()} | {error, any()}. iterator(DBHandle, ReadOpts, keys_only) -> CallerRef = make_ref(), async_iterator(CallerRef, DBHandle, ReadOpts, keys_only), ?WAIT_FOR_REPLY(CallerRef). async_iterator(_CallerRef, _DBHandle, _ReadOpts, keys_only) -> erlang:nif_error({error, not_loaded}). %% @doc Return a iterator over the contents of the specified column families. -spec iterators(DBHandle, CFHandles, ReadOpts) -> Res when DBHandle ::db_handle(), CFHandles :: [cf_handle()], ReadOpts :: read_options(), Res :: {ok, itr_handle()} | {error, any()}. iterators(DBHandle, CFHandles, ReadOpts) -> CallerRef = make_ref(), async_iterators(CallerRef, DBHandle, CFHandles, ReadOpts), ?WAIT_FOR_REPLY(CallerRef). async_iterators(_CallerRef, _DBHandle, _CFHandles, _ReadOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Return keys iterator over the contents of the specified column families. iterators(DBHandle, CFHandles, ReadOpts, keys_only) -> CallerRef = make_ref(), async_iterators(CallerRef, DBHandle, CFHandles, ReadOpts, keys_only), ?WAIT_FOR_REPLY(CallerRef); iterators(_, _, _, _) -> erlang:error(badarg). async_iterators(_CallerRef, _DBHandle, _CFHandles, _ReadOpts, keys_only) -> erlang:nif_error({error, not_loaded}). %% @doc Move to the specified place -spec iterator_move(ITRHandle, ITRAction) -> Res when ITRHandle::itr_handle(), ITRAction::iterator_action(), Res :: {ok, Key::binary(), Value::binary()} | {ok, Key::binary()} | {error, invalid_iterator} | {error, iterator_closed}. iterator_move(ITRHandle, ITRAction) -> case async_iterator_move(undefined, ITRHandle, ITRAction) of Ref when is_reference(Ref) -> receive {Ref, X} -> X end; {ok, _} = Key -> Key; {ok, _, _} = KeyVal -> KeyVal; ER -> ER end. async_iterator_move(_CallerRef, _ITRHandle, _ITRAction) -> erlang:nif_error({error, not_loaded}). %% @doc Close a iterator -spec iterator_close(ITRHandle::itr_handle()) -> ok. iterator_close(ITRHandle) -> CallerRef = make_ref(), async_iterator_close(CallerRef, ITRHandle), ?WAIT_FOR_REPLY(CallerRef). async_iterator_close(_CallerRef, _ITRHandle) -> erlang:nif_error({error, not_loaded}). -type fold_fun() :: fun(({Key::binary(), Value::binary()}, any()) -> any()). %% @doc Calls Fun(Elem, AccIn) on successive elements in the default column family %% starting with AccIn == Acc0. %% Fun/2 must return a new accumulator which is passed to the next call. %% The function returns the final value of the accumulator. %% Acc0 is returned if the default column family is empty. -spec fold(DBHandle, Fun, AccIn, ReadOpts) -> AccOut when DBHandle::db_handle(), Fun::fold_fun(), AccIn::any(), ReadOpts::read_options(), AccOut :: any(). fold(DBHandle, Fun, Acc0, ReadOpts) -> {ok, Itr} = iterator(DBHandle, ReadOpts), do_fold(Itr, Fun, Acc0). %% @doc Calls Fun(Elem, AccIn) on successive elements in the specified column family %% Other specs are same with fold/4 -spec fold(DBHandle, CFHandle, Fun, AccIn, ReadOpts) -> AccOut when DBHandle::db_handle(), CFHandle::cf_handle(), Fun::fold_fun(), AccIn::any(), ReadOpts::read_options(), AccOut :: any(). fold(_DBHandle, _CFHandle, _Fun, _Acc0, _ReadOpts) -> _Acc0. -type fold_keys_fun() :: fun((Key::binary(), any()) -> any()). %% @doc Calls Fun(Elem, AccIn) on successive elements in the default column family %% starting with AccIn == Acc0. %% Fun/2 must return a new accumulator which is passed to the next call. %% The function returns the final value of the accumulator. %% Acc0 is returned if the default column family is empty. -spec fold_keys(DBHandle, Fun, AccIn, ReadOpts) -> AccOut when DBHandle::db_handle(), Fun::fold_keys_fun(), AccIn::any(), ReadOpts::read_options(), AccOut :: any(). fold_keys(DBHandle, Fun, Acc0, ReadOpts) -> {ok, Itr} = iterator(DBHandle, ReadOpts, keys_only), do_fold(Itr, Fun, Acc0). %% @doc Calls Fun(Elem, AccIn) on successive elements in the specified column family %% Other specs are same with fold_keys/4 -spec fold_keys(DBHandle, CFHandle, Fun, AccIn, ReadOpts) -> AccOut when DBHandle::db_handle(), CFHandle::cf_handle(), Fun::fold_keys_fun(), AccIn::any(), ReadOpts::read_options(), AccOut :: any(). fold_keys(_DBHandle, _CFHandle, _Fun, _Acc0, _ReadOpts) -> _Acc0. %% @doc is the database empty -spec is_empty(DBHandle::db_handle()) -> true | false. is_empty(DbHandle) -> CallerRef = make_ref(), async_is_empty(CallerRef, DbHandle), ?WAIT_FOR_REPLY(CallerRef). async_is_empty(_CallerRef, _DBHandle) -> erlang:nif_error({error, not_loaded}). %% @doc Destroy the contents of the specified database. %% Be very careful using this method. -spec destroy(Name::file:filename_all(), DBOpts::db_options()) -> ok | {error, any()}. destroy(Name, DBOpts) -> CallerRef = make_ref(), async_destroy(CallerRef, Name, DBOpts), ?WAIT_FOR_REPLY(CallerRef). async_destroy(_CallerRef, _Name, _DBOpts) -> erlang:nif_error({error, not_loaded}). %% @doc Try to repair as much of the contents of the database as possible. %% Some data may be lost, so be careful when calling this function -spec repair(Name::file:filename_all(), DBOpts::db_options()) -> ok | {error, any()}. repair(Name, DBOpts) -> CallerRef = make_ref(), async_repair(CallerRef, Name, DBOpts), ?WAIT_FOR_REPLY(CallerRef). async_repair(_CallerRef, _Name, _DbOpts) -> erlang:nif_error({error, not_loaded}). %% @doc take a snapshot of a running RocksDB database in a separate directory %% http://rocksdb.org/blog/2609/use-checkpoints-for-efficient-snapshots/ -spec checkpoint( DbHandle::db_handle(), Path::file:filename_all() ) -> ok | {error, any()}. checkpoint(DbHandle, Path) -> CallerRef = make_ref(), async_checkpoint(CallerRef, DbHandle, Path), ?WAIT_FOR_REPLY(CallerRef). async_checkpoint(_Callerfef, _DbHandle, _Path) -> erlang:nif_error({error, not_loaded}). %% @doc Return the approximate number of keys in the default column family. %% Implemented by calling GetIntProperty with "rocksdb.estimate-num-keys" -spec count(DBHandle::db_handle()) -> non_neg_integer() | {error, any()}. count(DBHandle) -> count_1(get_property(DBHandle, <<"rocksdb.estimate-num-keys">>)). %% @doc %% Return the approximate number of keys in the specified column family. %% -spec count(DBHandle::db_handle(), CFHandle::cf_handle()) -> non_neg_integer() | {error, any()}. count(DBHandle, CFHandle) -> count_1(get_property(DBHandle, CFHandle, <<"rocksdb.estimate-num-keys">>)). count_1({ok, BinCount}) -> erlang:binary_to_integer(BinCount); count_1(Error) -> Error. %% @doc Return the current stats of the default column family %% Implemented by calling GetProperty with "rocksdb.stats" -spec stats(DBHandle::db_handle()) -> {ok, any()} | {error, any()}. stats(DBHandle) -> get_property(DBHandle, <<"rocksdb.stats">>). %% @doc Return the current stats of the specified column family %% Implemented by calling GetProperty with "rocksdb.stats" -spec stats( DBHandle::db_handle(), CFHandle::cf_handle() ) -> {ok, any()} | {error, any()}. stats(DBHandle, CfHandle) -> get_property(DBHandle, CfHandle, <<"rocksdb.stats">>). %% @doc Return the RocksDB internal status of the default column family specified at Property -spec get_property( DBHandle::db_handle(), Property::binary() ) -> {ok, any()} | {error, any()}. get_property(_DBHandle, _Property) -> erlang:nif_error({error, not_loaded}). %% @doc Return the RocksDB internal status of the specified column family specified at Property -spec get_property( DBHandle::db_handle(), CFHandle::cf_handle(), Property::binary() ) -> string() | {error, any()}. get_property(_DBHandle, _CFHandle, _Property) -> erlang:nif_error({error, not_loaded}). %% =================================================================== %% Internal functions %% =================================================================== do_fold(Itr, Fun, Acc0) -> try fold_loop(iterator_move(Itr, first), Itr, Fun, Acc0) after iterator_close(Itr) end. fold_loop({error, iterator_closed}, _Itr, _Fun, Acc0) -> throw({iterator_closed, Acc0}); fold_loop({error, invalid_iterator}, _Itr, _Fun, Acc0) -> Acc0; fold_loop({ok, K}, Itr, Fun, Acc0) -> Acc = Fun(K, Acc0), fold_loop(iterator_move(Itr, next), Itr, Fun, Acc); fold_loop({ok, K, V}, Itr, Fun, Acc0) -> Acc = Fun({K, V}, Acc0), fold_loop(iterator_move(Itr, next), Itr, Fun, Acc).