Add delete_set, a function needed to remove a series of records from a bucket.

storage/src/storage.erl

@@ -53,7 +53,7 @@ file:
     shrink/2]).
 
 % Public record operation functions
--export([delete/2, list/2, read/2, write/3, write/4]).
+-export([delete/2, delete_set/2, list/2, read/2, write/3, write/4]).
 
 % Module callbacks
 -export([code_change/3,
@@ -462,6 +462,30 @@ Spec:
 delete(Bucket, Key) ->
 	gen_server:call(?MODULE, {delete, Bucket, Key}).
 
+-doc """
+Delete a set of records based on the given metadata list.
+
+Spec:
+
+```
+-spec delete_set(Bucket, Metadata) -> ok | {error, Reason} when
+	Bucket :: atom(),
+	Metadata :: [{Key, Value}],
+	Key :: term(),
+	Value :: term(),
+	Reason :: term().
+```
+""".
+-spec delete_set(Bucket, Metadata) -> ok | {error, Reason} when
+	Bucket :: atom(),
+	Metadata :: [{Key, Value}],
+	Key :: term(),
+	Value :: term(),
+	Reason :: term().
+
+delete_set(Bucket, Metadata) ->
+	gen_server:call(?MODULE, {delete_set, Bucket, Metadata}).
+
 -doc """
 Spec:
 
@@ -704,6 +728,20 @@ handle_call({delete, Bucket, Key}, _From, State) ->
 		{aborted, Reason} -> {reply, {error, Reason}, State}
 	end;
 
+handle_call({delete_set, Bucket, Metadata}, _From, State) ->
+	Q = qlc:q([X || X <- mnesia:table(Bucket), filter(Metadata, X#object.metadata)]),
+
+	F = fun() ->
+		Recs = qlc:e(Q),
+
+		delete_matching(Bucket, Recs)
+	end,
+
+	case mnesia:transaction(F) of
+		{atomic, ok} -> {reply, ok, State};
+		{aborted, Reason} -> {reply, {error, Reason}, State}
+	end;
+
 handle_call({write, Bucket, Key, Term}, _From, State) ->
 	handle_call({write, Bucket, Key, Term, []}, _From, State);
 
@@ -792,3 +830,11 @@ filter([H | T], M) ->
 				true -> false
 			end
 	end.
+
+%
+% Delete all the records in a table for every key in the list.
+%
+delete_matching(_Bucket, []) -> ok;
+delete_matching(Bucket, [H | T]) ->
+	mnesia:delete(Bucket, H#object.key),
+	delete_matching(Bucket, T).