Merge pull request #22 from inaka/marcelog_delete_by_8

Marcelog delete by 8

examples/blog/run

@@ -57,7 +57,9 @@ main(_) ->
   io:format("Another Reader: ~p~n", [blog:find_reader(blog_reader:id(Reader))]),
 
   % Create a vote
-  _Vote = blog:new_vote(blog_reader:id(Reader2), blog_post:id(Post2)).
+  _Vote = blog:new_vote(blog_reader:id(Reader2), blog_post:id(Post2)),
+
+  io:format("Deleted ~p authors~n", [blog:del_author_by_name("Pepe Gorostiga")]).
 
 setup_codepath() ->
   Dir = filename:dirname(escript:script_name()),

examples/blog/src/blog.erl

@@ -34,8 +34,8 @@
 
 %%% Author API.
 -export([
-  new_author/2, save_author/1, del_author/0, del_author/1, find_author/1,
-  find_all_authors/2, find_authors_by_name/3
+  new_author/2, save_author/1, del_author/0, del_author/1, del_author_by_name/1,
+  find_author/1, find_all_authors/2, find_authors_by_name/3
 ]).
 
 %%% Reader API.
@@ -91,6 +91,11 @@ del_post() ->
 del_reader() ->
   sumo:delete_all(blog_reader).
 
+%% @doc Deletes the given author.
+-spec del_author_by_name(string()) -> pos_integer().
+del_author_by_name(Name) ->
+  sumo:delete_by(blog_author, [{name, Name}]).
+
 %% @doc Deletes the given author.
 -spec del_author(blog_author:author()) -> ok.
 del_author(Author) ->

src/sumo.erl

@@ -41,7 +41,7 @@
 -export([create_schema/0, create_schema/1, create_schema/2]).
 
 %%% API for standard CRUD functions.
--export([persist/2, delete/2, delete_all/1]).
+-export([persist/2, delete/2, delete_by/2, delete_all/1]).
 -export([find/2, find_all/1, find_all/4, find_by/2, find_by/4, find_one/2]).
 
 %%% API for repo handling.
@@ -179,13 +179,18 @@ delete_all(DocName) ->
 %% @doc Deletes the doc identified by Id.
 -spec delete(sumo_schema_name(), term()) -> ok.
 delete(DocName, Id) ->
-  case sumo_repo:delete(get_repo(DocName), DocName, Id) of
-    {ok, Result} ->
-      case Result of
-        true -> sumo_event:dispatch(DocName, deleted, [Id]);
-        false -> ok
-      end,
-      Result;
+  IdField = sumo:field_name(sumo:get_id_field(DocName)),
+  case delete_by(DocName, [{IdField, Id}]) of
+    1 -> sumo_event:dispatch(DocName, deleted, [Id]), true;
+    0 -> false
+  end.
+
+%% @doc Deletes the doc identified by Conditions.
+-spec delete_by(sumo_schema_name(), term()) -> ok.
+delete_by(DocName, Conditions) ->
+  case sumo_repo:delete_by(get_repo(DocName), DocName, Conditions) of
+    {ok, 0} -> 0;
+    {ok, NumRows} -> sumo_event:dispatch(DocName, deleted, [NumRows]), NumRows;
     Error -> throw(Error)
   end.
 

src/sumo_repo.erl

@@ -34,10 +34,11 @@
 %% Exports.
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %%% Public API.
--export([
-  create_schema/2, persist/2, find_all/2, find_all/5, find_by/3, find_by/5,
-  delete/3, delete_all/2, call/4
-]).
+-export([create_schema/2]).
+-export([persist/2]).
+-export([find_all/2, find_all/5, find_by/3, find_by/5]).
+-export([delete/3, delete_by/3, delete_all/2]).
+-export([call/4]).
 -export([start_link/3]).
 
 %%% Exports for gen_server
@@ -60,8 +61,8 @@
 -spec behaviour_info(callbacks) -> proplists:proplist()|undefined.
 behaviour_info(callbacks) ->
   [
-    {init,1}, {persist,2}, {delete,3}, {find_by,3}, {find_by,5},
-    {create_schema,2}
+    {init,1}, {persist,2}, {delete,3}, {delete_by, 3}, {delete_all, 2},
+    {find_by,3}, {find_by,5}, {create_schema,2}
   ];
 
 behaviour_info(_Other) ->
@@ -80,6 +81,11 @@ persist(Name, #sumo_doc{}=Doc) ->
 delete(Name, DocName, Id) ->
   gen_server:call(Name, {delete, DocName, Id}).
 
+%% @doc Deletes the docs identified by the given conditions.
+-spec delete_by(atom(), sumo_schema_name(), proplists:proplist()) -> ok.
+delete_by(Name, DocName, Conditions) ->
+  gen_server:call(Name, {delete_by, DocName, Conditions}).
+
 %% @doc Deletes all docs in the given repository name.
 -spec delete_all(atom(), sumo_schema_name()) -> ok.
 delete_all(Name, DocName) ->
@@ -151,6 +157,13 @@ handle_call(
   {OkOrError, Reply, NewState} = Handler:delete(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
+) ->
+  {OkOrError, Reply, NewState} = Handler:delete_by(DocName, Conditions, HState),
+  {reply, {OkOrError, Reply}, State#state{handler_state=NewState}};
+
 handle_call(
   {delete_all, DocName}, _From,
   #state{handler=Handler,handler_state=HState}=State

src/sumo_repo_mongo.erl

@@ -33,7 +33,7 @@
 %%% Public API.
 -export([
   init/1, create_schema/2, persist/2, find_by/3, find_by/5,
-  delete/3, delete_all/2
+  delete/3, delete_by/3, delete_all/2
 ]).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -67,6 +67,10 @@ delete(DocName, Id, #state{pool=Pool}=State) ->
   ),
   {ok, 1, State}.
 
+delete_by(DocName, Conditions, #state{pool=Pool}=State) ->
+  throw(not_implemented),
+  {ok, 0, State}.
+
 delete_all(DocName, #state{pool=Pool}=State) ->
   lager:debug("Dropping collection: ~p", [DocName]),
   ok = emongo:delete(Pool, atom_to_list(DocName)),

src/sumo_repo_mysql.erl

@@ -36,7 +36,7 @@
 -export([init/1]).
 -export([create_schema/2]).
 -export([persist/2]).
--export([delete/3, delete_all/2]).
+-export([delete/3, delete_by/3, delete_all/2]).
 -export([prepare/3, execute/2, execute/3]).
 -export([find_all/2, find_all/5, find_by/3, find_by/5]).
 
@@ -109,6 +109,22 @@ delete(DocName, Id, State) ->
     Error -> evaluate_execute_result(Error, State)
   end.
 
+delete_by(DocName, Conditions, State) ->
+  PreStatementName = list_to_atom("delete_by_" ++ string:join(
+    [atom_to_list(K) || {K, _V} <- Conditions],
+    "_"
+  )),
+  StatementName = prepare(DocName, PreStatementName, fun() -> [
+    "DELETE FROM ", escape(atom_to_list(DocName)),
+    " WHERE ",
+    [[escape(atom_to_list(K)), "=?"] || {K, _V} <- Conditions]
+  ] end),
+  Values = [V || {_K, V} <- Conditions],
+  case execute(StatementName, Values, State) of
+    #ok_packet{affected_rows = NumRows} -> {ok, NumRows, State};
+    Error -> evaluate_execute_result(Error, State)
+  end.
+
 delete_all(DocName, State) ->
   StatementName = prepare(DocName, delete_all, fun() ->
     ["DELETE FROM ", escape(atom_to_list(DocName))]

src/sumo_repo_redis.erl

@@ -35,7 +35,7 @@
 %% Public API.
 -export([
   init/1, create_schema/2, persist/2, find_by/3, find_by/5,
-  delete/3, delete_all/2, execute/2, execute/3
+  delete/3, delete_by/3, delete_all/2, execute/2, execute/3
 ]).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -67,13 +67,16 @@ persist(#sumo_doc{name=DocName, fields=Fields}=Doc, State) ->
   ),
   {ok, NewDoc, State}.
 
-delete(DocName, Id, State) ->
+delete_by(_DocName, _Conditions, _State) ->
   ok.
 
-delete_all(DocName, State) ->
+delete(_DocName, _Id, _State) ->
   ok.
 
-find_by(DocName, Conditions, Limit, Offset, State) ->
+delete_all(_DocName, _State) ->
+  ok.
+
+find_by(_DocName, _Conditions, _Limit, _Offset, _State) ->
   ok.
 
 find_by(DocName, Conditions, State) ->

src/sumo_repo_sqlite3.erl

@@ -35,7 +35,7 @@
 %% Public API.
 -export([
   init/1, create_schema/2, persist/2, find_by/3, find_by/5,
-  delete/3, delete_all/2, execute/2, execute/3
+  delete/3, delete_by/3, delete_all/2, execute/2, execute/3
 ]).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -53,6 +53,9 @@ persist(#sumo_doc{name=DocName}=Doc, State) ->
 delete(DocName, Id, State) ->
   ok.
 
+delete_by(DocName, Conditions, State) ->
+  ok.
+
 delete_all(DocName, State) ->
   ok.