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Diffstat (limited to 'src/shared/struct/shr_db_query.erl')
| -rw-r--r-- | src/shared/struct/shr_db_query.erl | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/src/shared/struct/shr_db_query.erl b/src/shared/struct/shr_db_query.erl new file mode 100644 index 0000000..284cc2c --- /dev/null +++ b/src/shared/struct/shr_db_query.erl @@ -0,0 +1,214 @@ +-module(shr_db_query). + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% TYPES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +-record +( + set_field, + { + field :: non_neg_integer(), + value :: any() + } +). + +-record +( + add_to_field, + { + field :: non_neg_integer(), + values :: list(any()), + head :: boolean() + } +). + +-record +( + update_indexed, + { + field :: non_neg_integer(), + ix :: non_neg_integer(), + ops :: list(db_query_op()) + } +). + +-record +( + set_perm, + { + perm :: shr_db_user:permission() + } +). + +-record +( + set_val, + { + val :: any() + } +). + +-record +( + db_query, + { + db :: atom(), + id :: any(), + user :: shr_db_user:user(), + ops :: list(db_query_master_op()) + } +). + +-type db_query_op() :: (#set_field{} | #add_to_field{} | #update_indexed{}). +-type db_query_master_op() :: (db_query_op() | #set_perm{} | #set_val{}). +-type db_query() :: #db_query{}. + +-opaque op() :: db_query_op(). +-opaque type() :: db_query(). + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% EXPORTS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +-export_type([type/0, op/0]). + +-export +( + [ + new/4, + set_field/2, + add_to_field/3, + update_indexed/3 + ] +). +-export +( + [ + get_database/1, + get_entry_id/1 + ] +). +-export([apply_to/2]). + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% LOCAL FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +-spec get_user (db_query()) -> shr_db_user:user(). +get_user (#db_query{ user = Result }) -> Result. + +-spec apply_update_indexed (#update_indexed{}, any()) -> any(). +apply_update_indexed (Op, Elem) -> + FieldNumber = Op#update_indexed.field, + IX = Op#update_indexed.ix, + Ops = Op#update_indexed.ops, + + IndexedFieldValue = element(FieldNumber, Elem), + ArrayValue = array:get(IX, IndexedFieldValue), + UpdatedArrayValue = lists:foldl(fun apply_op_to/2, ArrayValue, Ops), + UpdatedIndexedFieldValue = + array:set(IX, UpdatedArrayValue, IndexedFieldValue), + + setelement(FieldNumber, Elem, UpdatedIndexedFieldValue). + +-spec apply_add_to_field (#add_to_field{}, any()) -> any(). +apply_add_to_field (Op, Elem) -> + FieldNumber = Op#add_to_field.field, + NewValues = Op#add_to_field.values, + AddToHead = Op#add_to_field.head, + + CurrentValues = element(FieldNumber, Elem), + UpdatedValues = + case AddToHead of + true -> (NewValues ++ CurrentValues); + _ -> (CurrentValues ++ NewValues) + end, + + setelement(FieldNumber, Elem, UpdatedValues). + +-spec apply_set_field (#set_field{}, any()) -> any(). +apply_set_field (Op, Elem) -> + FieldNumber = Op#set_field.field, + NewValue = Op#set_field.value, + + setelement(FieldNumber, Elem, NewValue). + +-spec apply_op_to (db_query_op(), any()) -> any(). +apply_op_to (Op, Elem) when is_record(Op, set_field) -> + apply_set_field(Op, Elem); +apply_op_to (Op, Elem) when is_record(Op, add_to_field) -> + apply_add_to_field(Op, Elem); +apply_op_to (Op, Elem) when is_record(Op, update_indexed) -> + apply_update_indexed(Op, Elem). + +-spec apply_master_op_to + ( + db_query_master_op(), + shr_db_item:type() + ) + -> shr_db_item:type(). +apply_master_op_to (MOp, Elem) when is_record(MOp, set_perm) -> + NewPerm = MOp#set_perm.perm, + + shr_db_item:set_permission(NewPerm, Elem); +apply_master_op_to (MOp, Elem) when is_record(MOp, set_val) -> + NewVal = MOp#set_val.val, + + shr_db_item:set_value(NewVal, Elem); +apply_master_op_to (MOp, Elem) -> + OldValue = shr_db_item:get_value(Elem), + NewValue = apply_op_to(MOp, OldValue), + + shr_db_item:set_value(NewValue, Elem). + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%% EXPORTED FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +-spec new (atom(), any(), shr_db_user:user(), list(op())) -> type(). +new (DBName, ObjectID, User, Ops) -> + #db_query + { + db = DBName, + id = ObjectID, + user = User, + ops = Ops + }. + +-spec set_field (non_neg_integer(), any()) -> op(). +set_field (Field, Value) -> + #set_field { field = Field, value = Value }. + +-spec add_to_field (non_neg_integer(), list(any()), boolean()) -> op(). +add_to_field (Field, Values, IsPrefix) -> + #add_to_field { field = Field, values = Values, head = IsPrefix}. + +-spec update_indexed + ( + non_neg_integer(), + non_neg_integer(), + list(op()) + ) + -> op(). +update_indexed (Field, IX, Updates) -> + #update_indexed { field = Field, ix = IX, ops = Updates}. + +-spec get_database (db_query()) -> atom(). +get_database (#db_query{ db = Result }) -> Result. + +-spec get_entry_id (db_query()) -> any(). +get_entry_id (#db_query{ id = Result }) -> Result. + +-spec apply_to + ( + db_query(), + shr_db_item:type() + ) + -> ({'ok', shr_db_item:type()} | 'error'). +apply_to (DBQuery, DBItem) -> + true = + shr_db_user:can_access + ( + shr_db_item:get_permission(DBItem), + get_user(DBQuery) + ), + MOps = DBQuery#db_query.ops, + {ok, lists:foldl(fun apply_master_op_to/2, DBItem, MOps)}. + |