[tarantool-patches] [PATCH v2 1/1] schema:frommap() to create table or tuple

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

This feature is designed to build tuple or table object by map.
Tuple output is default. If you wish to make a table, specify table = true option.
subscriber:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {table = true})

Closes #3282
---
 src/box/lua/schema.lua  |   1 +
 src/box/lua/space.cc    | 123 ++++++++++++++++++++++++++++++++++++++++++++++++
 src/box/lua/tuple.c     |   2 +-
 src/box/lua/tuple.h     |   3 ++
 test/box/tuple.result   |  95 +++++++++++++++++++++++++++++++++++++
 test/box/tuple.test.lua |  29 ++++++++++++
 6 files changed, 252 insertions(+), 1 deletion(-)

diff --git a/src/box/lua/schema.lua b/src/box/lua/schema.lua
index 30c6bc6..323c2d6 100644
--- a/src/box/lua/schema.lua
+++ b/src/box/lua/schema.lua
@@ -1419,6 +1419,7 @@ function box.schema.space.bless(space)
         end
         builtin.space_run_triggers(s, yesno)
     end
+    space_mt.frommap = box.internal.space.frommap
     space_mt.__index = space_mt
 
     setmetatable(space, space_mt)
diff --git a/src/box/lua/space.cc b/src/box/lua/space.cc
index 29a9aca..2723baf 100644
--- a/src/box/lua/space.cc
+++ b/src/box/lua/space.cc
@@ -174,6 +174,16 @@ lbox_fillspace(struct lua_State *L, struct space *space, int i)
 	lua_pushstring(L, space->def->engine_name);
 	lua_settable(L, i);
 
+	/* space._schema_version */
+	lua_pushstring(L, "_schema_version");
+	luaL_pushuint64(L, box_schema_version());
+	lua_settable(L, i);
+
+	/* space._cptr */
+	lua_pushstring(L, "_cptr");
+	lua_pushlightuserdata(L, space);
+	lua_settable(L, i);
+
 	lua_pushstring(L, "enabled");
 	lua_pushboolean(L, space_index(space, 0) != 0);
 	lua_settable(L, i);
@@ -386,6 +396,111 @@ static struct trigger on_alter_space_in_lua = {
 	RLIST_LINK_INITIALIZER, box_lua_space_new_or_delete, NULL, NULL
 };
 
+/**
+ * Get a C pointer for space structure.
+ * Caches the result. Cleans the user(negative) stack itself.
+ * @param Lua space object at top of the Lua stack.
+ * @retval not nil C structure pointer.
+ * @retval nil, err Can not find underlying space, error
+ *         description is returned.
+ */
+static int
+lbox_space_ptr_cached(struct lua_State *L)
+{
+	if (lua_gettop(L) < 1 || !lua_istable(L, 1))
+		luaL_error(L, "Usage: space:_cptr()");
+
+	lua_getfield(L, 1, "_schema_version");
+	uint64_t schema_version = luaL_touint64(L, -1);
+	lua_pop(L, 1);
+	uint64_t global_shema_version = box_schema_version();
+
+	void *space = NULL;
+	if (schema_version == global_shema_version) {
+		lua_getfield(L, 1, "_cptr");
+		space = (void *)lua_topointer(L, -1);
+	} else {
+		lua_getfield(L, 1, "id");
+		uint32_t id = luaL_touint64(L, -1);
+		space = space_by_id(id);
+		if (space == NULL) {
+			lua_pushnil(L);
+			lua_pushstring(L, tt_sprintf("Space with id '%d' "\
+						     "doesn't exist", id));
+			return 2;
+		}
+
+		/** update the cache */
+		luaL_pushuint64(L, global_shema_version);
+		lua_setfield(L, 1, "_schema_version");
+		lua_pushlightuserdata(L, space);
+		lua_setfield(L, 1, "_cptr");
+	}
+	lua_pop(L, 1);
+	lua_pushlightuserdata(L, space);
+	return 1;
+}
+
+/**
+ * Make a tuple or a table Lua object by map.
+ * @param Lua space object.
+ * @param Lua map table object.
+ * @param Lua opts table object (optional).
+ * @retval not nil A tuple or a table conforming to a space
+ *         format.
+ * @retval nil, err Can not built a tuple. A reason is returned in
+ *         the second value.
+ */
+static int
+lbox_space_frommap(struct lua_State *L)
+{
+	struct tuple_dictionary *dict = NULL;
+	struct space *space = NULL;
+	int rc, argc = lua_gettop(L);
+	bool table = false;
+	if (argc < 2 || argc > 3 || !lua_istable(L, 2))
+		goto usage_error;
+	if (argc == 3) {
+		if (!lua_istable(L, 3))
+			goto usage_error;
+		lua_getfield(L, 3, "table");
+		if (!lua_isboolean(L, -1) && !lua_isnil(L, -1))
+			goto usage_error;
+		table = lua_toboolean(L, -1);
+	}
+
+	rc = lbox_space_ptr_cached(L);
+	if (rc != 1)
+		return rc;
+	space = (struct space *) lua_topointer(L, -1);
+	dict = space->format->dict;
+	lua_createtable(L, space->def->field_count, 0);
+
+	lua_pushnil(L);
+	while (lua_next(L, 2) != 0) {
+		uint32_t fieldno;
+		size_t key_len;
+		const char *key = lua_tolstring(L, -2, &key_len);
+		uint32_t key_hash = lua_hashstring(L, -2);
+		if (tuple_fieldno_by_name(dict, key, key_len, key_hash,
+					  &fieldno)) {
+			lua_pushnil(L);
+			lua_pushstring(L, tt_sprintf("Unknown field '%s'",
+						     key));
+			return 2;
+		}
+		lua_rawseti(L, -3, fieldno+1);
+	}
+	if (table)
+		return 1;
+
+	lua_replace(L, 1);
+	lua_settop(L, 1);
+	return lbox_tuple_new(L);
+usage_error:
+	return luaL_error(L, "Usage: space:frommap(map, opts)");
+}
+
 void
 box_lua_space_init(struct lua_State *L)
 {
@@ -464,4 +579,12 @@ box_lua_space_init(struct lua_State *L)
 	lua_pushnumber(L, VCLOCK_MAX);
 	lua_setfield(L, -2, "REPLICA_MAX");
 	lua_pop(L, 2); /* box, schema */
+
+	static const struct luaL_Reg space_internal_lib[] = {
+		{"frommap", lbox_space_frommap},
+		{"_cptr", lbox_space_ptr_cached},
+		{NULL, NULL}
+	};
+	luaL_register(L, "box.internal.space", space_internal_lib);
+	lua_pop(L, 1);
 }
diff --git a/src/box/lua/tuple.c b/src/box/lua/tuple.c
index 7ca4299..92a7185 100644
--- a/src/box/lua/tuple.c
+++ b/src/box/lua/tuple.c
@@ -90,7 +90,7 @@ luaT_istuple(struct lua_State *L, int narg)
 	return *(struct tuple **) data;
 }
 
-static int
+int
 lbox_tuple_new(lua_State *L)
 {
 	int argc = lua_gettop(L);
diff --git a/src/box/lua/tuple.h b/src/box/lua/tuple.h
index 0965644..5d7062e 100644
--- a/src/box/lua/tuple.h
+++ b/src/box/lua/tuple.h
@@ -66,6 +66,9 @@ luaT_istuple(struct lua_State *L, int idx);
 
 /** \endcond public */
 
+int
+lbox_tuple_new(struct lua_State *L);
+
 static inline int
 luaT_pushtupleornil(struct lua_State *L, struct tuple *tuple)
 {
diff --git a/test/box/tuple.result b/test/box/tuple.result
index ec5ed90..2dd8f0d 100644
--- a/test/box/tuple.result
+++ b/test/box/tuple.result
@@ -1060,6 +1060,101 @@ box.tuple.bsize == t.bsize
 ---
 - true
 ...
+--
+-- gh-3282: space:frommap().
+--
+format = {}
+---
+...
+format[1] = {name = 'aaa', type = 'unsigned'}
+---
+...
+format[2] = {name = 'bbb', type = 'unsigned'}
+---
+...
+format[3] = {name = 'ccc', type = 'unsigned'}
+---
+...
+format[4] = {name = 'ddd', type = 'unsigned'}
+---
+...
+s = box.schema.create_space('test', {format = format})
+---
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+---
+- [2, 4, 3, 1]
+...
+s:frommap({ddd = 1, aaa = 2, bbb = 3})
+---
+- [2, 3, null, 1]
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, eee = 4})
+---
+- null
+- Unknown field 'eee'
+...
+s:frommap()
+---
+- error: 'Usage: space:frommap(map, opts)'
+...
+s:frommap({})
+---
+- []
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {table = true})
+---
+- - 2
+  - 4
+  - 3
+  - 1
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {table = false})
+---
+- [2, 4, 3, 1]
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = box.NULL})
+---
+- [2, null, 3, 1]
+...
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {dummy = true})
+---
+- [2, 4, 3, 1]
+...
+_ = s:create_index('primary', {parts = {'aaa'}})
+---
+...
+tuple = s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+---
+...
+s:replace(tuple)
+---
+- [2, 4, 3, 1]
+...
+_, err = box.internal.space._cptr(s)
+---
+...
+assert(not err)
+---
+- true
+...
+s:drop()
+---
+...
+_, err = s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+---
+...
+assert(err ~= nil)
+---
+- true
+...
+_, err = box.internal.space._cptr(s)
+---
+...
+assert(err ~= nil)
+---
+- true
+...
 test_run:cmd("clear filter")
 ---
 - true
diff --git a/test/box/tuple.test.lua b/test/box/tuple.test.lua
index 0b3392d..03e6194 100644
--- a/test/box/tuple.test.lua
+++ b/test/box/tuple.test.lua
@@ -349,4 +349,33 @@ box.tuple.update == t.update
 box.tuple.upsert == t.upsert
 box.tuple.bsize == t.bsize
 
+--
+-- gh-3282: space:frommap().
+--
+format = {}
+format[1] = {name = 'aaa', type = 'unsigned'}
+format[2] = {name = 'bbb', type = 'unsigned'}
+format[3] = {name = 'ccc', type = 'unsigned'}
+format[4] = {name = 'ddd', type = 'unsigned'}
+s = box.schema.create_space('test', {format = format})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+s:frommap({ddd = 1, aaa = 2, bbb = 3})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, eee = 4})
+s:frommap()
+s:frommap({})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {table = true})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {table = false})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = box.NULL})
+s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4}, {dummy = true})
+_ = s:create_index('primary', {parts = {'aaa'}})
+tuple = s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+s:replace(tuple)
+_, err = box.internal.space._cptr(s)
+assert(not err)
+s:drop()
+_, err = s:frommap({ddd = 1, aaa = 2, ccc = 3, bbb = 4})
+assert(err ~= nil)
+_, err = box.internal.space._cptr(s)
+assert(err ~= nil)
+
 test_run:cmd("clear filter")
-- 
2.7.4