[#275] – Remove the need for mnesia's start_phase magic

README.md

@@ -60,8 +60,7 @@ And you can check all of our open-source projects at
 
 These three concepts have a specific meaning in the context of sumo_db.
 
- - **Backend**: holds the connection to a single instance of a database, which
- can be MySql, MongoDB, ElasticSearch or any other that's implemented.
+ - **Backend**: establishes and holds a single Database instance connection.
 
  - **Store**: implements the specific operations that modify the contents of the
  backend and retrieves the information it holds.
@@ -71,10 +70,26 @@ These three concepts have a specific meaning in the context of sumo_db.
  that bridges the model and the store.
 
 
+## Supported Backends/Adapters
+
+ - [Mnesia](http://erlang.org/doc/man/mnesia.html) is built-in in `sumo`
+ - [Riak](https://github.com/inaka/sumo_db_riak)
+ - [PostgreSQL](https://github.com/inaka/sumo_db_pgsql)
+ - [MySQL](https://github.com/inaka/sumo_db_mysql)
+ - [MongoDB](https://github.com/inaka/sumo_db_mongo)
+ - [ElasticSearch](https://github.com/inaka/sumo_db_elasticsearch)
+
+
 ## Implementing an Adapter
 
-TO implement an adapter, you must implement two behaviors: `sumo_backend` and
-`sumo_store`.
+To implement an adapter, you must implement two specific behaviours:
+
+ - [**sumo_backend**](./src/sumo_backend.erl) – DB connection
+ - [**sumo_store**](./src/sumo_store.erl) – implements the **Sumo API**
+
+ > You can check the implemented adapters mentioned above in order to have
+   a better idea about how to build a custom adapter from scratch.
+
 
 ## Events
 
@@ -119,6 +134,7 @@ Sumo requires users to add their own `gen_event`'s in order to handle those even
 ```
 Sumo allows us to add a `gen_event` to one type of model (i.e. `people`) or for all (`'_'`).
 
+
 ## Example
 
 See: [**examples/blog**][example-blog] for a full example. To run it, while

elvis.config

@@ -1,24 +1,23 @@
 [
- {
-   elvis,
-   [
-    {config,
-     [#{dirs => ["src/*", "test"],
-        filter => "*.erl",
-        rules => [{elvis_style, dont_repeat_yourself, disable},
-                  {elvis_style, invalid_dynamic_call, disable}],
-        ruleset => erl_files
-       },
-      #{dirs => ["."],
-        filter => "rebar.config",
-        ruleset => rebar_config
-       },
-      #{dirs => ["."],
-        filter => "elvis.config",
-        ruleset => elvis_config
-       }
-     ]
-    }
-   ]
- }
+ {elvis, [
+   {config, [
+     #{dirs => ["src/*", "test"],
+       filter => "*.erl",
+       rules => [
+         {elvis_style, dont_repeat_yourself, disable},
+         {elvis_style, invalid_dynamic_call, disable},
+         {elvis_style, line_length, #{limit => 100}}
+       ],
+       ruleset => erl_files
+     },
+     #{dirs => ["."],
+       filter => "rebar.config",
+       ruleset => rebar_config
+     },
+     #{dirs => ["."],
+       filter => "elvis.config",
+      ruleset => elvis_config
+     }
+   ]}
+ ]}
 ].

src/adapter_test_helpers/sumo_test_people.erl

@@ -65,7 +65,7 @@
 %%%=============================================================================
 
 -spec sumo_schema() -> no_return().
-sumo_schema() -> throw(should_be_implemented_by_children).
+sumo_schema() -> exit(should_be_implemented_by_children).
 
 -spec sumo_sleep(Person :: person()) -> sumo:model().
 sumo_sleep(Person) ->

src/adapters/sumo_backend_mnesia.erl

@@ -57,7 +57,15 @@ start_link(Name, Options) ->
 %%%=============================================================================
 
 -spec init([term()]) -> {ok, state()}.
-init(_Options) -> {ok, #{}}.
+init(_Options) ->
+  Node = node(),
+  _ = application:stop(mnesia),
+  _ = case mnesia:create_schema([Node]) of
+    ok -> ok;
+    {error, {Node, {already_exists, Node}}} -> ok
+  end,
+  {ok, _} = application:ensure_all_started(mnesia),
+  {ok, #{}}.
 
 -spec handle_call(term(), term(), state()) -> {reply, term(), state()}.
 handle_call(Msg, _From, State) -> {reply, {unexpected_message, Msg}, State}.

src/adapters/sumo_store_mnesia.erl

@@ -280,7 +280,7 @@ new_id(string)    -> uuid:uuid_to_string(uuid:get_v4(), standard);
 new_id(binary)    -> uuid:uuid_to_string(uuid:get_v4(), binary_standard);
 new_id(integer)   -> <<Id:128>> = uuid:get_v4(), Id;
 new_id(float)     -> <<Id:128>> = uuid:get_v4(), Id * 1.0;
-new_id(FieldType) -> throw({unimplemented, FieldType}).
+new_id(FieldType) -> exit({unimplemented, FieldType}).
 
 %% @doc http://www.erlang.org/doc/apps/erts/match_spec.html
 %% @private
@@ -346,7 +346,7 @@ condition_to_guard({Name, Value}, FieldsMap) ->
   condition_to_guard({Name, '==', Value}, FieldsMap).
 
 %% @private
-check_operator(like) -> throw({unsupported_operator, like});
+check_operator(like) -> exit({unsupported_operator, like});
 check_operator(Op)   -> sumo_internal:check_operator(Op).
 
 %% @private
@@ -379,9 +379,7 @@ result_to_doc(Result, Fields) ->
 
 %% @private
 transform_conditions(DocName, Conditions) ->
-  sumo_utils:transform_conditions(
-    fun validate_date/1, DocName, Conditions, [date]
-  ).
+  sumo_utils:transform_conditions(fun validate_date/1, DocName, Conditions, [date]).
 
 %% @private
 validate_date({FieldType, _, FieldValue}) ->

src/sumo.erl

@@ -207,9 +207,7 @@ find_by(DocName, Conditions, Limit, Offset) ->
 find_by(DocName, Conditions, SortFields, Limit, Offset) ->
   NormalizedSortFields = normalize_sort_fields(SortFields),
   Store = sumo_config:get_store(DocName),
-  case sumo_store:find_by(
-    Store, DocName, Conditions, NormalizedSortFields, Limit, Offset
-  ) of
+  case sumo_store:find_by(Store, DocName, Conditions, NormalizedSortFields, Limit, Offset) of
     {ok, Docs} -> docs_wakeup(Docs);
     Error      -> exit(Error)
   end.
@@ -249,10 +247,7 @@ delete_by(DocName, Conditions) ->
     {ok, 0} ->
       0;
     {ok, NumRows} ->
-      EventId = sumo_event:dispatch(DocName,
-                                    EventId,
-                                    deleted_total,
-                                    [NumRows, Conditions]),
+      EventId = sumo_event:dispatch(DocName, EventId, deleted_total, [NumRows, Conditions]),
       NumRows;
     Error ->
       exit(Error)
@@ -263,7 +258,7 @@ delete_by(DocName, Conditions) ->
 count(DocName) ->
   case sumo_store:count(sumo_config:get_store(DocName), DocName) of
     {ok, Total} -> Total;
-    Error       -> throw(Error)
+    Error       -> exit(Error)
   end.
 
 %% @doc Calls the given custom function of a store.

src/sumo_internal.erl

@@ -90,9 +90,7 @@ new_schema(Name, Fields) ->
   S.
 
 %% @doc Returns a new field of the given type and attributes.
--spec new_field(
-  sumo:field_name(), sumo:field_type(), sumo:field_attrs()
-) -> field().
+-spec new_field(sumo:field_name(), sumo:field_type(), sumo:field_attrs()) -> field().
 new_field(Name, Type, Attributes) ->
   #{name => Name, type => Type, attrs => Attributes}.
 
@@ -179,7 +177,7 @@ id_field_name(DocName) ->
 id_field_type(DocName) ->
   field_type(get_id_field(get_schema(DocName))).
 
-%% @doc Checks the operator is known, throws otherwise.
+%% @doc Checks the operator is known, exit otherwise.
 -spec check_operator(sumo:operator()) -> ok.
 check_operator('<') -> ok;
 check_operator('=<') -> ok;
@@ -188,7 +186,7 @@ check_operator('>=') -> ok;
 check_operator('==') -> ok;
 check_operator('/=') -> ok;
 check_operator('like') -> ok;
-check_operator(Op) -> throw({unknown_operator, Op}).
+check_operator(Op) -> exit({unknown_operator, Op}).
 
 -spec report_overrun(term()) -> ok.
 report_overrun(Report) ->

src/utils/sumo_sql_builder.erl

@@ -182,7 +182,7 @@ values_conditions({Name, Value}, {Values, CleanExprs, Count}) ->
 values_conditions([], Acc) ->
   Acc;
 values_conditions(Expr, _) ->
-  throw({unsupported_expression, Expr}).
+  exit({unsupported_expression, Expr}).
 
 -spec where_clause(sumo:conditions()) -> iodata().
 where_clause(Exprs) ->

src/utils/sumo_utils.erl

@@ -50,8 +50,7 @@ doc_transform(Fun, Doc) ->
   FieldValue         :: sumo:field_value(),
   ResTuple           :: {FieldName, FieldType, FieldValue},
   Response           :: [ResTuple].
-doc_filter_fields_by(DocNameOrDoc, FilteredFieldTypes)
-    when is_atom(DocNameOrDoc) ->
+doc_filter_fields_by(DocNameOrDoc, FilteredFieldTypes) when is_atom(DocNameOrDoc) ->
   filter_fields(DocNameOrDoc, undefined, FilteredFieldTypes);
 doc_filter_fields_by(DocNameOrDoc, FilteredFieldTypes) ->
   DocName = sumo_internal:doc_name(DocNameOrDoc),

test/sumo_test_utils.erl

@@ -5,11 +5,6 @@
 
 -spec start_apps() -> ok.
 start_apps() ->
-  ok = case mnesia:create_schema([node()]) of
-    ok -> ok;
-    {error, {_Host, {already_exists, _Host}}} -> ok
-  end,
-  {ok, _} = application:ensure_all_started(mnesia),
   {ok, _} = application:ensure_all_started(sumo_db),
   init_events(),
   ok.