datafusion_python/expr/
explain.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use std::fmt::{self, Display, Formatter};
19
20use datafusion::logical_expr::logical_plan::Explain;
21use datafusion::logical_expr::LogicalPlan;
22use pyo3::prelude::*;
23use pyo3::IntoPyObjectExt;
24
25use super::logical_node::LogicalNode;
26use crate::common::df_schema::PyDFSchema;
27use crate::errors::py_type_err;
28use crate::sql::logical::PyLogicalPlan;
29
30#[pyclass(frozen, name = "Explain", module = "datafusion.expr", subclass)]
31#[derive(Clone)]
32pub struct PyExplain {
33    explain: Explain,
34}
35
36impl From<PyExplain> for Explain {
37    fn from(explain: PyExplain) -> Self {
38        explain.explain
39    }
40}
41
42impl From<Explain> for PyExplain {
43    fn from(explain: Explain) -> PyExplain {
44        PyExplain { explain }
45    }
46}
47
48impl Display for PyExplain {
49    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
50        write!(
51            f,
52            "Explain
53            verbose: {:?}
54            plan: {:?}
55            stringified_plans: {:?}
56            schema: {:?}
57            logical_optimization_succeeded: {:?}",
58            &self.explain.verbose,
59            &self.explain.plan,
60            &self.explain.stringified_plans,
61            &self.explain.schema,
62            &self.explain.logical_optimization_succeeded
63        )
64    }
65}
66
67#[pymethods]
68impl PyExplain {
69    fn explain_string(&self) -> PyResult<Vec<String>> {
70        let mut string_plans: Vec<String> = Vec::new();
71        for stringified_plan in &self.explain.stringified_plans {
72            string_plans.push((*stringified_plan.plan).clone());
73        }
74        Ok(string_plans)
75    }
76
77    fn verbose(&self) -> bool {
78        self.explain.verbose
79    }
80
81    fn plan(&self) -> PyResult<PyLogicalPlan> {
82        Ok(PyLogicalPlan::from((*self.explain.plan).clone()))
83    }
84
85    fn schema(&self) -> PyDFSchema {
86        (*self.explain.schema).clone().into()
87    }
88
89    fn logical_optimization_succceeded(&self) -> bool {
90        self.explain.logical_optimization_succeeded
91    }
92}
93
94impl TryFrom<LogicalPlan> for PyExplain {
95    type Error = PyErr;
96
97    fn try_from(logical_plan: LogicalPlan) -> Result<Self, Self::Error> {
98        match logical_plan {
99            LogicalPlan::Explain(explain) => Ok(PyExplain { explain }),
100            _ => Err(py_type_err("unexpected plan")),
101        }
102    }
103}
104
105impl LogicalNode for PyExplain {
106    fn inputs(&self) -> Vec<PyLogicalPlan> {
107        vec![]
108    }
109
110    fn to_variant<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
111        self.clone().into_bound_py_any(py)
112    }
113}