risingwave_frontend/optimizer/rule/
table_function_to_postgres_query_rule.rs

1// Copyright 2024 RisingWave Labs
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use itertools::Itertools;
16use risingwave_common::catalog::{Field, Schema};
17use risingwave_common::types::{DataType, ScalarImpl};
18
19use super::prelude::{PlanRef, *};
20use crate::expr::{Expr, TableFunctionType};
21use crate::optimizer::plan_node::generic::GenericPlanRef;
22use crate::optimizer::plan_node::{LogicalPostgresQuery, LogicalTableFunction};
23
24/// Transform a special `TableFunction` (with `POSTGRES_QUERY` table function type) into a `LogicalPostgresQuery`
25pub struct TableFunctionToPostgresQueryRule {}
26impl Rule<Logical> for TableFunctionToPostgresQueryRule {
27    fn apply(&self, plan: PlanRef) -> Option<PlanRef> {
28        let logical_table_function: &LogicalTableFunction = plan.as_logical_table_function()?;
29        if logical_table_function.table_function().function_type != TableFunctionType::PostgresQuery
30        {
31            return None;
32        }
33        assert!(!logical_table_function.with_ordinality());
34        let table_function_return_type = logical_table_function.table_function().return_type();
35
36        if let DataType::Struct(st) = table_function_return_type {
37            let fields = st
38                .iter()
39                .map(|(name, data_type)| Field::with_name(data_type.clone(), name.to_owned()))
40                .collect_vec();
41
42            let schema = Schema::new(fields);
43
44            assert!(logical_table_function.table_function().args.len() >= 6);
45            let mut eval_args = vec![];
46            for arg in &logical_table_function.table_function().args {
47                assert_eq!(arg.return_type(), DataType::Varchar);
48                let value = arg.try_fold_const().unwrap().unwrap();
49                match value {
50                    Some(ScalarImpl::Utf8(s)) => {
51                        eval_args.push(s.to_string());
52                    }
53                    _ => {
54                        unreachable!("must be a varchar")
55                    }
56                }
57            }
58            let hostname = eval_args[0].clone();
59            let port = eval_args[1].clone();
60            let username = eval_args[2].clone();
61            let password = eval_args[3].clone();
62            let database = eval_args[4].clone();
63            let query = eval_args[5].clone();
64            let ssl_mode = eval_args.get(6).cloned();
65            let ssl_root_cert = eval_args.get(7).cloned();
66
67            Some(
68                LogicalPostgresQuery::new(
69                    logical_table_function.ctx(),
70                    schema,
71                    hostname,
72                    port,
73                    username,
74                    password,
75                    database,
76                    query,
77                    ssl_mode,
78                    ssl_root_cert,
79                )
80                .into(),
81            )
82        } else {
83            unreachable!("TableFunction return type should be struct")
84        }
85    }
86}
87
88impl TableFunctionToPostgresQueryRule {
89    pub fn create() -> BoxedRule {
90        Box::new(TableFunctionToPostgresQueryRule {})
91    }
92}
risingwave_frontend/optimizer/rule/table_function_to_postgres_query_rule.rs

risingwave_frontend/optimizer/rule/
table_function_to_postgres_query_rule.rs
