datafusion-functions 44.0.0

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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//! "crypto" DataFusion functions
use super::basic::{sha256, utf8_or_binary_to_binary_type};
use arrow::datatypes::DataType;
use datafusion_common::Result;
use datafusion_expr::scalar_doc_sections::DOC_SECTION_HASHING;
use datafusion_expr::{
    ColumnarValue, Documentation, ScalarUDFImpl, Signature, Volatility,
};
use std::any::Any;
use std::sync::OnceLock;

#[derive(Debug)]
pub struct SHA256Func {
    signature: Signature,
}
impl Default for SHA256Func {
    fn default() -> Self {
        Self::new()
    }
}

impl SHA256Func {
    pub fn new() -> Self {
        use DataType::*;
        Self {
            signature: Signature::uniform(
                1,
                vec![Utf8View, Utf8, LargeUtf8, Binary, LargeBinary],
                Volatility::Immutable,
            ),
        }
    }
}
impl ScalarUDFImpl for SHA256Func {
    fn as_any(&self) -> &dyn Any {
        self
    }

    fn name(&self) -> &str {
        "sha256"
    }

    fn signature(&self) -> &Signature {
        &self.signature
    }

    fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
        utf8_or_binary_to_binary_type(&arg_types[0], self.name())
    }

    fn invoke_batch(
        &self,
        args: &[ColumnarValue],
        _number_rows: usize,
    ) -> Result<ColumnarValue> {
        sha256(args)
    }

    fn documentation(&self) -> Option<&Documentation> {
        Some(get_sha256_doc())
    }
}

static DOCUMENTATION: OnceLock<Documentation> = OnceLock::new();

fn get_sha256_doc() -> &'static Documentation {
    DOCUMENTATION.get_or_init(|| {
        Documentation::builder(
            DOC_SECTION_HASHING,
            "Computes the SHA-256 hash of a binary string.",
            "sha256(expression)",
        )
        .with_sql_example(
            r#"```sql
> select sha256('foo');
+--------------------------------------+
| sha256(Utf8("foo"))                  |
+--------------------------------------+
| <sha256_hash_result>                 |
+--------------------------------------+
```"#,
        )
        .with_standard_argument("expression", Some("String"))
        .build()
    })
}