datafusion_python/expr/
literal.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 crate::errors::PyDataFusionError;
19use datafusion::{common::ScalarValue, logical_expr::expr::FieldMetadata};
20use pyo3::{prelude::*, IntoPyObjectExt};
21
22#[pyclass(name = "Literal", module = "datafusion.expr", subclass)]
23#[derive(Clone)]
24pub struct PyLiteral {
25    pub value: ScalarValue,
26    pub metadata: Option<FieldMetadata>,
27}
28
29impl PyLiteral {
30    pub fn new_with_metadata(value: ScalarValue, metadata: Option<FieldMetadata>) -> PyLiteral {
31        Self { value, metadata }
32    }
33}
34
35impl From<PyLiteral> for ScalarValue {
36    fn from(lit: PyLiteral) -> ScalarValue {
37        lit.value
38    }
39}
40
41impl From<ScalarValue> for PyLiteral {
42    fn from(value: ScalarValue) -> PyLiteral {
43        PyLiteral {
44            value,
45            metadata: None,
46        }
47    }
48}
49
50macro_rules! extract_scalar_value {
51    ($self: expr, $variant: ident) => {
52        match &$self.value {
53            ScalarValue::$variant(value) => Ok(*value),
54            other => Err(unexpected_literal_value(other)),
55        }
56    };
57}
58
59#[pymethods]
60impl PyLiteral {
61    /// Get the data type of this literal value
62    fn data_type(&self) -> String {
63        format!("{}", self.value.data_type())
64    }
65
66    pub fn value_f32(&self) -> PyResult<Option<f32>> {
67        extract_scalar_value!(self, Float32)
68    }
69
70    pub fn value_f64(&self) -> PyResult<Option<f64>> {
71        extract_scalar_value!(self, Float64)
72    }
73
74    pub fn value_decimal128(&mut self) -> PyResult<(Option<i128>, u8, i8)> {
75        match &self.value {
76            ScalarValue::Decimal128(value, precision, scale) => Ok((*value, *precision, *scale)),
77            other => Err(unexpected_literal_value(other)),
78        }
79    }
80
81    pub fn value_i8(&self) -> PyResult<Option<i8>> {
82        extract_scalar_value!(self, Int8)
83    }
84
85    pub fn value_i16(&self) -> PyResult<Option<i16>> {
86        extract_scalar_value!(self, Int16)
87    }
88
89    pub fn value_i32(&self) -> PyResult<Option<i32>> {
90        extract_scalar_value!(self, Int32)
91    }
92
93    pub fn value_i64(&self) -> PyResult<Option<i64>> {
94        extract_scalar_value!(self, Int64)
95    }
96
97    pub fn value_u8(&self) -> PyResult<Option<u8>> {
98        extract_scalar_value!(self, UInt8)
99    }
100
101    pub fn value_u16(&self) -> PyResult<Option<u16>> {
102        extract_scalar_value!(self, UInt16)
103    }
104
105    pub fn value_u32(&self) -> PyResult<Option<u32>> {
106        extract_scalar_value!(self, UInt32)
107    }
108
109    pub fn value_u64(&self) -> PyResult<Option<u64>> {
110        extract_scalar_value!(self, UInt64)
111    }
112
113    pub fn value_date32(&self) -> PyResult<Option<i32>> {
114        extract_scalar_value!(self, Date32)
115    }
116
117    pub fn value_date64(&self) -> PyResult<Option<i64>> {
118        extract_scalar_value!(self, Date64)
119    }
120
121    pub fn value_time64(&self) -> PyResult<Option<i64>> {
122        extract_scalar_value!(self, Time64Nanosecond)
123    }
124
125    pub fn value_timestamp(&mut self) -> PyResult<(Option<i64>, Option<String>)> {
126        match &self.value {
127            ScalarValue::TimestampNanosecond(iv, tz)
128            | ScalarValue::TimestampMicrosecond(iv, tz)
129            | ScalarValue::TimestampMillisecond(iv, tz)
130            | ScalarValue::TimestampSecond(iv, tz) => {
131                Ok((*iv, tz.as_ref().map(|s| s.as_ref().to_string())))
132            }
133            other => Err(unexpected_literal_value(other)),
134        }
135    }
136
137    pub fn value_bool(&self) -> PyResult<Option<bool>> {
138        extract_scalar_value!(self, Boolean)
139    }
140
141    pub fn value_string(&self) -> PyResult<Option<String>> {
142        match &self.value {
143            ScalarValue::Utf8(value) => Ok(value.clone()),
144            other => Err(unexpected_literal_value(other)),
145        }
146    }
147
148    pub fn value_interval_day_time(&self) -> PyResult<Option<(i32, i32)>> {
149        match &self.value {
150            ScalarValue::IntervalDayTime(Some(iv)) => Ok(Some((iv.days, iv.milliseconds))),
151            ScalarValue::IntervalDayTime(None) => Ok(None),
152            other => Err(unexpected_literal_value(other)),
153        }
154    }
155
156    #[allow(clippy::wrong_self_convention)]
157    fn into_type<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
158        self.clone().into_bound_py_any(py)
159    }
160
161    fn __repr__(&self) -> PyResult<String> {
162        Ok(format!("{}", self.value))
163    }
164}
165
166fn unexpected_literal_value(value: &ScalarValue) -> PyErr {
167    PyDataFusionError::Common(format!("getValue<T>() - Unexpected value: {value}")).into()
168}
datafusion_python/expr/literal.rs

datafusion_python/expr/
literal.rs
