Merge pull request #266 from inaka/cabol.265.refactor_sumo_find_by

Cabol.265.refactor_sumo_find_by

examples/blog/src/blog.erl

@@ -57,17 +57,17 @@ find_authors_by_name(Name, Limit, Offset) ->
 %% @doc Finds a post given the id.
 -spec find_post(blog_post:id()) -> blog_post:post()|notfound.
 find_post(Id) ->
-  sumo:find(post, Id).
+  sumo:fetch(post, Id).
 
 %% @doc Finds an author, given the id.
 -spec find_author(blog_author:id()) -> blog_author:author()|notfound.
 find_author(Id) ->
-  sumo:find(author, Id).
+  sumo:fetch(author, Id).
 
 %% @doc Find a reader, given the id.
 -spec find_reader(blog_reader:id()) -> blog_reader:reader()|notfound.
 find_reader(Id) ->
-  sumo:find(reader, Id).
+  sumo:fetch(reader, Id).
 
 %% @doc Returns all available posts.
 -spec total_posts() -> non_neg_integer().

src/adapter_test_helpers/sumo_basic_test_helper.erl

@@ -32,9 +32,10 @@ find(Config) ->
   Module = sumo_config:get_prop_value(Name, module),
 
   [First, Second | _] = sumo:find_all(Name),
-  First = sumo:find(Name, Module:id(First)),
-  Second = sumo:find(Name, Module:id(Second)),
-  notfound = sumo:find(Name, 0),
+  First = sumo:find_one(Name, [{id, Module:id(First)}]),
+  Second = sumo:fetch(Name, Module:id(Second)),
+  notfound = sumo:fetch(Name, 0),
+  notfound = sumo:find_one(Name, [{id, 0}]),
   ok.
 
 -spec find_all(config()) -> ok.
@@ -141,7 +142,7 @@ check_proper_dates(Config) ->
   Module = sumo_config:get_prop_value(Name, module),
 
   [P0] = sumo:find_by(Name, [{name, <<"A">>}]),
-  P1 = sumo:find(Name, Module:id(P0)),
+  P1 = sumo:fetch(Name, Module:id(P0)),
   [P2 | _] = sumo:find_all(Name),
 
   {Date, _} = calendar:universal_time(),

src/adapters/sumo_store_mnesia.erl

@@ -28,6 +28,7 @@
   init/1,
   create_schema/2,
   persist/2,
+  fetch/3,
   delete_by/3,
   delete_all/2,
   find_all/2, find_all/5,
@@ -81,6 +82,21 @@ persist(Doc, State) ->
       {ok, NewDoc, State}
   end.
 
+-spec fetch(DocName, Id, State) -> Response when
+  DocName  :: sumo:schema_name(),
+  Id       :: sumo:field_value(),
+  State    :: state(),
+  Response :: sumo_store:result(sumo_internal:doc(), state()).
+fetch(DocName, Id, State) ->
+  try
+    [Result] = mnesia:dirty_read(DocName, Id),
+    Schema = sumo_internal:get_schema(DocName),
+    Fields = schema_field_names(Schema),
+    {ok, wakeup(result_to_doc(Result, Fields)), State}
+  catch
+    _:_ -> {error, notfound, State}
+  end.
+
 -spec delete_by(sumo:schema_name(), sumo:conditions(), state()) ->
   sumo_store:result(sumo_store:affected_rows(), state()).
 delete_by(DocName, Conditions, State) ->

src/sumo.erl

@@ -38,13 +38,13 @@
 %%% API for standard CRUD functions.
 -export([
   persist/2,
+  fetch/2,
+  find_one/2,
+  find_all/1, find_all/4,
+  find_by/2, find_by/4, find_by/5,
   delete/2,
   delete_by/2,
   delete_all/1,
-  find/2,
-  find_all/1, find_all/4,
-  find_by/2, find_by/4, find_by/5,
-  find_one/2,
   call/2, call/3
 ]).
 
@@ -110,33 +110,38 @@
 %%% Code starts here.
 %%%=============================================================================
 
-%% @doc Returns all the configured docs.
--spec get_docs() -> [{atom(), atom()}].
-get_docs() ->
-  {ok, Docs} = application:get_env(sumo_db, docs),
-  Docs.
+%% @doc Creates or updates the given Doc.
+-spec persist(schema_name(), UserDoc) -> UserDoc.
+persist(DocName, State) ->
+  Module = sumo_config:get_prop_value(DocName, module),
+  DocMap = Module:sumo_sleep(State),
+  Store = sumo_config:get_store(DocName),
+  case sumo_store:persist(Store, sumo_internal:new_doc(DocName, DocMap)) of
+    {ok, NewDoc} ->
+      Ret = sumo_internal:wakeup(NewDoc),
+      sumo_event:dispatch(DocName, persisted, [Ret]),
+      Ret;
+    Error ->
+      throw(Error)
+  end.
 
-%% @doc Creates the schema for all known (configured) docs.
--spec create_schema() -> ok.
-create_schema() ->
-  lists:foreach(fun({DocName, _, _}) ->
-    create_schema(DocName)
-  end, get_docs()).
+%% @doc Returns the doc identified by Id.
+-spec fetch(schema_name(), field_value()) -> user_doc() | notfound.
+fetch(DocName, Id) ->
+  Store = sumo_config:get_store(DocName),
+  case sumo_store:fetch(Store, DocName, Id) of
+    {ok, Doc}       -> sumo_internal:wakeup(Doc);
+    {error, Reason} -> Reason
+  end.
 
 %% @doc Returns 1 doc that matches the given Conditions.
 -spec find_one(schema_name(), conditions()) -> user_doc() | notfound.
 find_one(DocName, Conditions) ->
   case find_by(DocName, Conditions, 1, 0) of
-    []   -> notfound;
-    List -> hd(List)
+    []          -> notfound;
+    [First | _] -> First
   end.
 
-%% @doc Returns the doc identified by Id.
--spec find(schema_name(), field_value()) -> user_doc() | notfound.
-find(DocName, Id) ->
-  IdFieldName = sumo_internal:id_field_name(DocName),
-  find_one(DocName, [{IdFieldName, Id}]).
-
 %% @doc Returns all docs from the given store.
 -spec find_all(schema_name()) -> [user_doc()].
 find_all(DocName) ->
@@ -201,31 +206,12 @@ 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
+    Store, DocName, Conditions, NormalizedSortFields, Limit, Offset
+  ) of
     {ok, Docs} -> docs_wakeup(Docs);
     Error      -> throw(Error)
   end.
 
-%% @doc Creates or updates the given Doc.
--spec persist(schema_name(), UserDoc) -> UserDoc.
-persist(DocName, State) ->
-  IdField = sumo_internal:id_field_name(DocName),
-  Module = sumo_config:get_prop_value(DocName, module),
-  DocMap = Module:sumo_sleep(State),
-  EventName = case maps:get(IdField, DocMap, undefined) of
-    undefined -> created;
-    _         -> updated
-  end,
-  Store = sumo_config:get_store(DocName),
-  case sumo_store:persist(Store, sumo_internal:new_doc(DocName, DocMap)) of
-    {ok, NewDoc} ->
-      Ret = sumo_internal:wakeup(NewDoc),
-      sumo_event:dispatch(DocName, EventName, [Ret]),
-      Ret;
-    Error ->
-      throw(Error)
-  end.
-
 %% @doc Deletes all docs of type DocName.
 -spec delete_all(schema_name()) -> non_neg_integer().
 delete_all(DocName) ->
@@ -264,6 +250,27 @@ delete_by(DocName, Conditions) ->
       throw(Error)
   end.
 
+%% @doc Calls the given custom function of a store.
+-spec call(schema_name(), atom()) -> term().
+call(DocName, Function) ->
+  call(DocName, Function, []).
+
+%% @doc Calls the given custom function of a store with the given args.
+-spec call(schema_name(), atom(), [term()]) -> term().
+call(DocName, Function, Args) ->
+  Store = sumo_config:get_store(DocName),
+  case sumo_store:call(Store, DocName, Function, Args) of
+    {ok, {docs, Docs}} -> docs_wakeup(Docs);
+    {ok, {raw, Value}} -> Value
+  end.
+
+%% @doc Creates the schema for all known (configured) docs.
+-spec create_schema() -> ok.
+create_schema() ->
+  lists:foreach(fun({DocName, _, _}) ->
+    create_schema(DocName)
+  end, get_docs()).
+
 %% @doc Creates the schema for the docs of type DocName.
 -spec create_schema(schema_name()) -> ok.
 create_schema(DocName) ->
@@ -282,20 +289,6 @@ create_schema(DocName, Store) ->
       throw(Error)
   end.
 
-%% @doc Calls the given custom function of a store.
--spec call(schema_name(), atom()) -> term().
-call(DocName, Function) ->
-  call(DocName, Function, []).
-
-%% @doc Calls the given custom function of a store with the given args.
--spec call(schema_name(), atom(), [term()]) -> term().
-call(DocName, Function, Args) ->
-  Store = sumo_config:get_store(DocName),
-  case sumo_store:call(Store, DocName, Function, Args) of
-    {ok, {docs, Docs}} -> docs_wakeup(Docs);
-    {ok, {raw, Value}} -> Value
-  end.
-
 %% @doc Returns a new schema.
 -spec new_schema(schema_name(), [field()]) -> schema().
 new_schema(Name, Fields) ->
@@ -326,3 +319,7 @@ normalize_sort_fields({Name, Order}) ->
   [{Name, Order}];
 normalize_sort_fields(SortFields) when is_list(SortFields) ->
   lists:flatmap(fun normalize_sort_fields/1, SortFields).
+
+%% @private
+get_docs() ->
+  application:get_env(sumo_db, docs, []).

src/sumo_store.erl

@@ -28,6 +28,7 @@
   start_link/3,
   create_schema/2,
   persist/2,
+  fetch/3,
   delete_by/3,
   delete_all/2,
   find_all/2,
@@ -75,6 +76,11 @@
   Doc :: sumo_internal:doc(),
   Res :: result(sumo_internal:doc(), State).
 
+-callback fetch(Schema, Id, State) -> Res when
+  Schema :: sumo:schema_name(),
+  Id     :: sumo:field_value(),
+  Res    :: result(sumo_internal:doc(), State).
+
 -callback delete_by(Schema, Conditions, State) -> Res when
   Schema     :: sumo:schema_name(),
   Conditions :: sumo:conditions(),
@@ -147,6 +153,15 @@ create_schema(Name, Schema) ->
 persist(Name, Doc) ->
   wpool:call(Name, {persist, Doc}).
 
+%% @doc Fetch a single doc by its `Id'.
+-spec fetch(Name, DocName, Id) -> Res when
+  Name    :: atom(),
+  DocName :: sumo:schema_name(),
+  Id      :: sumo:field_value(),
+  Res     :: {ok, sumo_internal:doc()} | {error, term()}.
+fetch(Name, DocName, Id) ->
+  wpool:call(Name, {fetch, DocName, Id}).
+
 %% @doc Deletes the docs identified by the given conditions.
 -spec delete_by(Name, DocName, Conditions) -> Res when
   Name       :: atom(),
@@ -264,6 +279,13 @@ handle_call(
   {OkOrError, Reply, NewState} = Handler:persist(Doc, HState),
   {reply, {OkOrError, Reply}, State#state{handler_state=NewState}};
 
+handle_call(
+  {fetch, DocName, Id}, _From,
+  #state{handler = Handler, handler_state = HState} = State
+) ->
+  {OkOrError, Reply, NewState} = Handler:fetch(DocName, Id, HState),
+  {reply, {OkOrError, Reply}, State#state{handler_state=NewState}};
+
 handle_call(
   {delete_by, DocName, Conditions}, _From,
   #state{handler = Handler, handler_state = HState} = State