support json type

src/sql/engine/expr/ob_expr_json_pretty.cpp

@@ -0,0 +1,158 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+// This file is for implementation of func json_pretty
+#define USING_LOG_PREFIX SQL_ENG
+#include "ob_expr_json_pretty.h"
+#include "sql/engine/expr/ob_expr_json_func_helper.h"
+
+using namespace oceanbase::common;
+using namespace oceanbase::sql;
+
+namespace oceanbase
+{
+namespace sql
+{
+
+ObExprJsonPretty::ObExprJsonPretty(ObIAllocator &alloc) 
+      :ObFuncExprOperator(alloc,
+      T_FUN_SYS_JSON_PRETTY,
+      N_JSON_PRETTY, 
+      1, NOT_ROW_DIMENSION)
+{
+}
+
+ObExprJsonPretty::~ObExprJsonPretty()
+{
+}
+
+int ObExprJsonPretty::calc_result_type1(ObExprResType &type,
+                                        ObExprResType &type1,
+                                        common::ObExprTypeCtx &type_ctx) const
+{
+  UNUSED(type_ctx); // type_ctx session, collation, raw expr, maybe should use type_ctx in oracle mode to judge character set
+  INIT_SUCC(ret);
+
+  type.set_type(ObLongTextType);
+  type.set_collation_type(CS_TYPE_UTF8MB4_BIN);
+  type.set_collation_level(CS_LEVEL_IMPLICIT);
+
+  if (OB_FAIL(ObJsonExprHelper::is_valid_for_json(type1, 1, N_JSON_PRETTY))) {
+    LOG_WARN("wrong type for json doc.", K(ret), K(type1.get_type()));
+  }
+
+  return ret;
+}
+
+template <typename T>
+int ObExprJsonPretty::calc(const T &data, ObObjType type, ObCollationType cs_type,
+                           ObIAllocator *allocator, ObJsonBuffer &j_buf, bool &is_null)
+{
+  INIT_SUCC(ret);
+  ObIJsonBase *j_base = NULL;
+  ObJsonInType j_in_type = ObJsonExprHelper::get_json_internal_type(type);
+  common::ObString j_text = data.get_string(); // json text or json binary
+
+  if (OB_ISNULL(allocator)) { // check allocator
+    ret = OB_NOT_INIT;
+    LOG_WARN("allcator is null", K(ret));
+  } else if (data.is_null() || type == ObNullType) {
+    is_null = true;
+  } else if (type != ObJsonType && !ob_is_string_type(type)) {
+    ret = OB_ERR_INVALID_TYPE_FOR_JSON;
+    LOG_USER_ERROR(OB_ERR_INVALID_TYPE_FOR_JSON, 1, "json_pretty");
+  } else if (OB_FAIL(ObJsonExprHelper::ensure_collation(type, cs_type))) {
+    LOG_WARN("fail to ensure collation", K(ret), K(type), K(cs_type));
+  } else if (OB_FAIL(ObJsonBaseFactory::get_json_base(allocator, j_text, j_in_type,
+      j_in_type, j_base))) {
+    LOG_WARN("fail to get json base", K(ret), K(type), K(j_text), K(j_in_type));
+  } else if (OB_FAIL(j_base->print(j_buf, true, true))) {
+    LOG_WARN("fail to print json", K(ret), K(type), K(j_text), K(j_in_type));
+  }
+
+  return ret;
+}
+
+// for old sql engine
+int ObExprJsonPretty::calc_result1(common::ObObj &result, const common::ObObj &obj,
+                                   common::ObExprCtx &expr_ctx) const
+{
+  INIT_SUCC(ret);
+  ObIAllocator *allocator = expr_ctx.calc_buf_;
+  ObObjType type = obj.get_type();
+  ObCollationType cs_type = obj.get_collation_type();
+  ObJsonBuffer j_buf(allocator);
+  bool is_null = false;
+
+  if (OB_FAIL(calc(obj, type, cs_type, allocator, j_buf, is_null))) {
+    LOG_WARN("fail to calc json pretty result", K(ret), K(obj), K(type), K(cs_type));
+  } else if (is_null) {
+    result.set_null();
+  } else {
+    char *buf = static_cast<char*>(allocator->alloc(j_buf.length()));
+    if (buf) {
+      MEMMOVE(buf, j_buf.ptr(), j_buf.length());
+      result.set_string(ObLongTextType, buf, j_buf.length());
+      result.set_collation_type(result_type_.get_collation_type());
+    } else {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("fail to alloc memory for result", K(ret), K(j_buf));
+    }
+  }
+
+  return ret;
+}
+
+// for new sql engine
+int ObExprJsonPretty::eval_json_pretty(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &res)
+{
+  INIT_SUCC(ret);
+  common::ObArenaAllocator &tmp_allocator = ctx.get_reset_tmp_alloc();
+  ObExpr *arg = expr.args_[0];
+  ObDatum *j_datum = NULL;
+  ObObjType type = arg->datum_meta_.type_;
+  ObCollationType cs_type = arg->datum_meta_.cs_type_;
+  ObJsonBuffer j_buf(&tmp_allocator);
+  bool is_null = false;
+
+  if (OB_FAIL(arg->eval(ctx, j_datum))) {
+    ret = OB_ERR_INVALID_DATATYPE;
+    LOG_WARN("error, eval json args datum failed", K(ret));
+  } else if (OB_FAIL(calc(*j_datum, type, cs_type, &tmp_allocator, j_buf, is_null))) {
+    LOG_WARN("fail to calc json pretty result", K(ret), K(j_datum), K(type), K(cs_type));
+  } else if (is_null) {
+    res.set_null();
+  } else {
+    char *buf = expr.get_str_res_mem(ctx, j_buf.length());
+    if (buf) {
+      MEMMOVE(buf, j_buf.ptr(), j_buf.length());
+      res.set_string(buf, j_buf.length());        
+    } else {
+      ret = OB_ALLOCATE_MEMORY_FAILED;
+      LOG_WARN("fail to alloc memory for json pretty result", K(ret), K(j_buf));
+    }
+  }
+
+  return ret;
+}
+
+int ObExprJsonPretty::cg_expr(ObExprCGCtx &expr_cg_ctx, const ObRawExpr &raw_expr,
+                              ObExpr &rt_expr) const
+{
+  UNUSED(expr_cg_ctx);
+  UNUSED(raw_expr);
+  rt_expr.eval_func_ = eval_json_pretty;
+  return OB_SUCCESS;
+}
+
+}
+}