wip(): add type definitions

README.md

@@ -1,6 +1,7 @@
 # Rox
 
-**TODO: Add description**
+Elixir wrapper around
+[leo-project/erocksdb](https://github.com/leo-project/erocksdb)
 
 ## Installation
 
@@ -13,12 +14,3 @@ If [available in Hex](https://hex.pm/docs/publish), the package can be installed
       [{:rox, "~> 0.1.0"}]
     end
     ```
-
-  2. Ensure `rox` is started before your application:
-
-    ```elixir
-    def application do
-      [applications: [:rox]]
-    end
-    ```
-

lib/rox.ex

@@ -1,2 +1,148 @@
 defmodule Rox do
+  @opts_to_convert_to_bitlists [:db_log_dir, :wal_dir]
+
+  @type compaction_style :: :level | :universal | :fifo | :none
+  @type compression_type :: :snappy | :zlib | :bzip2 | :lz4 | :lz4h | :none
+
+  @type db_handle :: binary
+  @type cf_handle :: binary
+  @type itr_handle :: binary
+  @type snapshot_handle :: binary
+
+  @type file_path :: String.t
+
+
+  @type block_based_table_options :: [
+    {:no_block_cache, boolean} |
+    {:block_size, pos_integer} |
+    {:block_cache_size, pos_integer} |
+    {:bloom_filter_policy, bits_per_key :: 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} |
+    {:expanded_compaction_factor,  pos_integer} |
+    {:source_compaction_factor,  pos_integer} |
+    {:max_grandparent_overlap_factor,  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_path :: {:db_path, name :: String.t, options :: cf_options}
+  @type cf_descriptor :: {:cf_descriptor, name :: String.t, options :: cf_options}
+  @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
+
+  @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, [db_path]} |
+    {:db_log_dir, file_path} |
+    {:wal_dir, file_path} |
+    {: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}
+  ]
+
+  @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, cf_handle, key :: binary, value :: binary} |
+    {:delete, key :: binary} |
+    {:delete, cf_handle, key :: binary} |
+    :clear
+  ]
+
+  @type iterator_action :: :first | :last | :next | :prev | binary
+
+  @doc """
+  Open a RocksDB with the specified read options
+  """
+
+  @spec open(path :: file_path, db_opts :: db_options, cf_opts :: cf_options) :: {:ok, db_handle} | {:error, any}
+  def open(path, db_opts \\ [], cf_opts \\ []) do
+    :erocksdb.open(to_charlist(path), sanitize_opts(db_opts), sanitize_opts(cf_opts))
+  end
+
+  defp sanitize_opts(opts) do
+    [ raw, rest ] = Keyword.split(opts, @opts_to_convert_to_bitlists)
+    converted = Enum.map(raw, fn {k, val} -> {k, to_charlist(val)} end)
+    Keyword.merge(rest, converted)
+  end
 end

mix.exs

@@ -27,6 +27,8 @@ defmodule Rox.Mixfile do
   #
   # Type "mix help deps" for more examples and options
   defp deps do
-    []
+    [
+      {:erocksdb, "~> 0.4.1"}
+    ]
   end
 end

mix.lock

@@ -0,0 +1 @@
+%{"erocksdb": {:hex, :erocksdb, "0.4.1", "59a3258b1460d0e64f7575d912d9af86fa5aa56729abff18e4d3e4fd4a5e01e0", [:rebar3], []}}