datafusion_functions/datetime/
from_unixtime.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::any::Any;
19use std::sync::Arc;
20
21use arrow::datatypes::DataType::{Int64, Timestamp, Utf8};
22use arrow::datatypes::TimeUnit::Second;
23use arrow::datatypes::{DataType, Field, FieldRef};
24use datafusion_common::{exec_err, internal_err, Result, ScalarValue};
25use datafusion_expr::TypeSignature::Exact;
26use datafusion_expr::{
27    ColumnarValue, Documentation, ReturnFieldArgs, ScalarUDFImpl, Signature, Volatility,
28};
29use datafusion_macros::user_doc;
30
31#[user_doc(
32    doc_section(label = "Time and Date Functions"),
33    description = "Converts an integer to RFC3339 timestamp format (`YYYY-MM-DDT00:00:00.000000000Z`). Integers and unsigned integers are interpreted as seconds since the unix epoch (`1970-01-01T00:00:00Z`) return the corresponding timestamp.",
34    syntax_example = "from_unixtime(expression[, timezone])",
35    sql_example = r#"```sql
36> select from_unixtime(1599572549, 'America/New_York');
37+-----------------------------------------------------------+
38| from_unixtime(Int64(1599572549),Utf8("America/New_York")) |
39+-----------------------------------------------------------+
40| 2020-09-08T09:42:29-04:00                                 |
41+-----------------------------------------------------------+
42```"#,
43    standard_argument(name = "expression",),
44    argument(
45        name = "timezone",
46        description = "Optional timezone to use when converting the integer to a timestamp. If not provided, the default timezone is UTC."
47    )
48)]
49#[derive(Debug)]
50pub struct FromUnixtimeFunc {
51    signature: Signature,
52}
53
54impl Default for FromUnixtimeFunc {
55    fn default() -> Self {
56        Self::new()
57    }
58}
59
60impl FromUnixtimeFunc {
61    pub fn new() -> Self {
62        Self {
63            signature: Signature::one_of(
64                vec![Exact(vec![Int64, Utf8]), Exact(vec![Int64])],
65                Volatility::Immutable,
66            ),
67        }
68    }
69}
70
71impl ScalarUDFImpl for FromUnixtimeFunc {
72    fn as_any(&self) -> &dyn Any {
73        self
74    }
75
76    fn name(&self) -> &str {
77        "from_unixtime"
78    }
79
80    fn signature(&self) -> &Signature {
81        &self.signature
82    }
83
84    fn return_field_from_args(&self, args: ReturnFieldArgs) -> Result<FieldRef> {
85        // Length check handled in the signature
86        debug_assert!(matches!(args.scalar_arguments.len(), 1 | 2));
87
88        if args.scalar_arguments.len() == 1 {
89            Ok(Field::new(self.name(), Timestamp(Second, None), true).into())
90        } else {
91            args.scalar_arguments[1]
92                .and_then(|sv| {
93                    sv.try_as_str()
94                        .flatten()
95                        .filter(|s| !s.is_empty())
96                        .map(|tz| {
97                            Field::new(
98                                self.name(),
99                                Timestamp(Second, Some(Arc::from(tz.to_string()))),
100                                true,
101                            )
102                        })
103                })
104                .map(Arc::new)
105                .map_or_else(
106                    || {
107                        exec_err!(
108                            "{} requires its second argument to be a constant string",
109                            self.name()
110                        )
111                    },
112                    Ok,
113                )
114        }
115    }
116
117    fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
118        internal_err!("call return_field_from_args instead")
119    }
120
121    fn invoke_with_args(
122        &self,
123        args: datafusion_expr::ScalarFunctionArgs,
124    ) -> Result<ColumnarValue> {
125        let args = args.args;
126        let len = args.len();
127        if len != 1 && len != 2 {
128            return exec_err!(
129                "from_unixtime function requires 1 or 2 argument, got {}",
130                args.len()
131            );
132        }
133
134        if args[0].data_type() != Int64 {
135            return exec_err!(
136                "Unsupported data type {:?} for function from_unixtime",
137                args[0].data_type()
138            );
139        }
140
141        match len {
142            1 => args[0].cast_to(&Timestamp(Second, None), None),
143            2 => match &args[1] {
144                ColumnarValue::Scalar(ScalarValue::Utf8(Some(tz))) => args[0]
145                    .cast_to(&Timestamp(Second, Some(Arc::from(tz.to_string()))), None),
146                _ => {
147                    exec_err!(
148                        "Unsupported data type {:?} for function from_unixtime",
149                        args[1].data_type()
150                    )
151                }
152            },
153            _ => unreachable!(),
154        }
155    }
156
157    fn documentation(&self) -> Option<&Documentation> {
158        self.doc()
159    }
160}
161
162#[cfg(test)]
163mod test {
164    use crate::datetime::from_unixtime::FromUnixtimeFunc;
165    use arrow::datatypes::TimeUnit::Second;
166    use arrow::datatypes::{DataType, Field};
167    use datafusion_common::ScalarValue;
168    use datafusion_common::ScalarValue::Int64;
169    use datafusion_expr::{ColumnarValue, ScalarUDFImpl};
170    use std::sync::Arc;
171
172    #[test]
173    fn test_without_timezone() {
174        let arg_field = Arc::new(Field::new("a", DataType::Int64, true));
175        let args = datafusion_expr::ScalarFunctionArgs {
176            args: vec![ColumnarValue::Scalar(Int64(Some(1729900800)))],
177            arg_fields: vec![arg_field],
178            number_rows: 1,
179            return_field: Field::new("f", DataType::Timestamp(Second, None), true).into(),
180        };
181        let result = FromUnixtimeFunc::new().invoke_with_args(args).unwrap();
182
183        match result {
184            ColumnarValue::Scalar(ScalarValue::TimestampSecond(Some(sec), None)) => {
185                assert_eq!(sec, 1729900800);
186            }
187            _ => panic!("Expected scalar value"),
188        }
189    }
190
191    #[test]
192    fn test_with_timezone() {
193        let arg_fields = vec![
194            Field::new("a", DataType::Int64, true).into(),
195            Field::new("a", DataType::Utf8, true).into(),
196        ];
197        let args = datafusion_expr::ScalarFunctionArgs {
198            args: vec![
199                ColumnarValue::Scalar(Int64(Some(1729900800))),
200                ColumnarValue::Scalar(ScalarValue::Utf8(Some(
201                    "America/New_York".to_string(),
202                ))),
203            ],
204            arg_fields,
205            number_rows: 2,
206            return_field: Field::new(
207                "f",
208                DataType::Timestamp(Second, Some(Arc::from("America/New_York"))),
209                true,
210            )
211            .into(),
212        };
213        let result = FromUnixtimeFunc::new().invoke_with_args(args).unwrap();
214
215        match result {
216            ColumnarValue::Scalar(ScalarValue::TimestampSecond(Some(sec), Some(tz))) => {
217                assert_eq!(sec, 1729900800);
218                assert_eq!(tz.to_string(), "America/New_York");
219            }
220            _ => panic!("Expected scalar value"),
221        }
222    }
223}
datafusion_functions/datetime/from_unixtime.rs

datafusion_functions/datetime/
from_unixtime.rs
