Simplify Spark sha2 implementation (#19475)

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- Part of #12725

## Rationale for this change

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in the issue then this section is not needed.
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Simplify implementation, also remove usage of user_defined.

## What changes are included in this PR?

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Refactor to be simpler.

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Added tests.

## Are there any user-facing changes?

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No.

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Co-authored-by: Andrew Lamb <andrew@nerdnetworks.org>

Author: Jefffrey

Cargo.lock

@@ -181,6 +181,7 @@ recursive = "0.1.1"
 regex = "1.12"
 rstest = "0.26.1"
 serde_json = "1"
+sha2 = "^0.10.9"
 sqlparser = { version = "0.60.0", default-features = false, features = ["std", "visitor"] }
 strum = "0.27.2"
 strum_macros = "0.27.2"

Cargo.toml

@@ -85,7 +85,7 @@ md-5 = { version = "^0.10.0", optional = true }
 num-traits = { workspace = true }
 rand = { workspace = true }
 regex = { workspace = true, optional = true }
-sha2 = { version = "^0.10.9", optional = true }
+sha2 = { workspace = true, optional = true }
 unicode-segmentation = { version = "^1.7.1", optional = true }
 uuid = { workspace = true, features = ["v4"], optional = true }
 

datafusion/functions/Cargo.toml

@@ -60,6 +60,7 @@ log = { workspace = true }
 percent-encoding = "2.3.2"
 rand = { workspace = true }
 sha1 = "0.10"
+sha2 = { workspace = true }
 url = { workspace = true }
 
 [dev-dependencies]

datafusion/spark/Cargo.toml

@@ -15,26 +15,30 @@
 // specific language governing permissions and limitations
 // under the License.
 
-extern crate datafusion_functions;
-
-use crate::function::error_utils::{
-    invalid_arg_count_exec_err, unsupported_data_type_exec_err,
-};
-use crate::function::math::hex::spark_sha2_hex;
-use arrow::array::{ArrayRef, AsArray, StringArray};
+use arrow::array::{ArrayRef, AsArray, BinaryArrayType, Int32Array, StringArray};
 use arrow::datatypes::{DataType, Int32Type};
-use datafusion_common::{Result, ScalarValue, exec_err, internal_datafusion_err};
-use datafusion_expr::Signature;
-use datafusion_expr::{ColumnarValue, ScalarFunctionArgs, ScalarUDFImpl, Volatility};
-pub use datafusion_functions::crypto::basic::{sha224, sha256, sha384, sha512};
+use datafusion_common::types::{
+    NativeType, logical_binary, logical_int32, logical_string,
+};
+use datafusion_common::utils::take_function_args;
+use datafusion_common::{Result, internal_err};
+use datafusion_expr::{
+    Coercion, ColumnarValue, ScalarFunctionArgs, ScalarUDFImpl, Signature,
+    TypeSignatureClass, Volatility,
+};
+use datafusion_functions::utils::make_scalar_function;
+use sha2::{self, Digest};
 use std::any::Any;
+use std::fmt::Write;
 use std::sync::Arc;
 
+/// Differs from DataFusion version in allowing array input for bit lengths, and
+/// also hex encoding the output.
+///
 /// <https://spark.apache.org/docs/latest/api/sql/index.html#sha2>
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub struct SparkSha2 {
     signature: Signature,
-    aliases: Vec<String>,
 }
 
 impl Default for SparkSha2 {
@@ -46,8 +50,21 @@ impl Default for SparkSha2 {
 impl SparkSha2 {
     pub fn new() -> Self {
         Self {
-            signature: Signature::user_defined(Volatility::Immutable),
-            aliases: vec![],
+            signature: Signature::coercible(
+                vec![
+                    Coercion::new_implicit(
+                        TypeSignatureClass::Native(logical_binary()),
+                        vec![TypeSignatureClass::Native(logical_string())],
+                        NativeType::Binary,
+                    ),
+                    Coercion::new_implicit(
+                        TypeSignatureClass::Native(logical_int32()),
+                        vec![TypeSignatureClass::Integer],
+                        NativeType::Int32,
+                    ),
+                ],
+                Volatility::Immutable,
+            ),
         }
     }
 }
@@ -65,163 +82,73 @@ impl ScalarUDFImpl for SparkSha2 {
         &self.signature
     }
 
-    fn return_type(&self, arg_types: &[DataType]) -> Result<DataType> {
-        if arg_types[1].is_null() {
-            return Ok(DataType::Null);
-        }
-        Ok(match arg_types[0] {
-            DataType::Utf8View
-            | DataType::LargeUtf8
-            | DataType::Utf8
-            | DataType::Binary
-            | DataType::BinaryView
-            | DataType::LargeBinary => DataType::Utf8,
-            DataType::Null => DataType::Null,
-            _ => {
-                return exec_err!(
-                    "{} function can only accept strings or binary arrays.",
-                    self.name()
-                );
-            }
-        })
+    fn return_type(&self, _arg_types: &[DataType]) -> Result<DataType> {
+        Ok(DataType::Utf8)
     }
 
     fn invoke_with_args(&self, args: ScalarFunctionArgs) -> Result<ColumnarValue> {
-        let args: [ColumnarValue; 2] = args.args.try_into().map_err(|_| {
-            internal_datafusion_err!("Expected 2 arguments for function sha2")
-        })?;
-
-        sha2(args)
+        make_scalar_function(sha2_impl, vec![])(&args.args)
     }
+}
 
-    fn aliases(&self) -> &[String] {
-        &self.aliases
-    }
+fn sha2_impl(args: &[ArrayRef]) -> Result<ArrayRef> {
+    let [values, bit_lengths] = take_function_args("sha2", args)?;
 
-    fn coerce_types(&self, arg_types: &[DataType]) -> Result<Vec<DataType>> {
-        if arg_types.len() != 2 {
-            return Err(invalid_arg_count_exec_err(
-                self.name(),
-                (2, 2),
-                arg_types.len(),
-            ));
+    let bit_lengths = bit_lengths.as_primitive::<Int32Type>();
+    let output = match values.data_type() {
+        DataType::Binary => sha2_binary_impl(&values.as_binary::<i32>(), bit_lengths),
+        DataType::LargeBinary => {
+            sha2_binary_impl(&values.as_binary::<i64>(), bit_lengths)
         }
-        let expr_type = match &arg_types[0] {
-            DataType::Utf8View
-            | DataType::LargeUtf8
-            | DataType::Utf8
-            | DataType::Binary
-            | DataType::BinaryView
-            | DataType::LargeBinary
-            | DataType::Null => Ok(arg_types[0].clone()),
-            _ => Err(unsupported_data_type_exec_err(
-                self.name(),
-                "String, Binary",
-                &arg_types[0],
-            )),
-        }?;
-        let bit_length_type = if arg_types[1].is_numeric() {
-            Ok(DataType::Int32)
-        } else if arg_types[1].is_null() {
-            Ok(DataType::Null)
-        } else {
-            Err(unsupported_data_type_exec_err(
-                self.name(),
-                "Numeric Type",
-                &arg_types[1],
-            ))
-        }?;
-
-        Ok(vec![expr_type, bit_length_type])
-    }
+        DataType::BinaryView => sha2_binary_impl(&values.as_binary_view(), bit_lengths),
+        dt => return internal_err!("Unsupported datatype for sha2: {dt}"),
+    };
+    Ok(output)
 }
 
-pub fn sha2(args: [ColumnarValue; 2]) -> Result<ColumnarValue> {
-    match args {
-        [
-            ColumnarValue::Scalar(ScalarValue::Utf8(expr_arg)),
-            ColumnarValue::Scalar(ScalarValue::Int32(Some(bit_length_arg))),
-        ] => compute_sha2(
-            bit_length_arg,
-            &[ColumnarValue::from(ScalarValue::Utf8(expr_arg))],
-        ),
-        [
-            ColumnarValue::Array(expr_arg),
-            ColumnarValue::Scalar(ScalarValue::Int32(Some(bit_length_arg))),
-        ] => compute_sha2(bit_length_arg, &[ColumnarValue::from(expr_arg)]),
-        [
-            ColumnarValue::Scalar(ScalarValue::Utf8(expr_arg)),
-            ColumnarValue::Array(bit_length_arg),
-        ] => {
-            let arr: StringArray = bit_length_arg
-                .as_primitive::<Int32Type>()
-                .iter()
-                .map(|bit_length| {
-                    match sha2([
-                        ColumnarValue::Scalar(ScalarValue::Utf8(expr_arg.clone())),
-                        ColumnarValue::Scalar(ScalarValue::Int32(bit_length)),
-                    ])
-                    .unwrap()
-                    {
-                        ColumnarValue::Scalar(ScalarValue::Utf8(str)) => str,
-                        ColumnarValue::Array(arr) => arr
-                            .as_string::<i32>()
-                            .iter()
-                            .map(|str| str.unwrap().to_string())
-                            .next(), // first element
-                        _ => unreachable!(),
-                    }
-                })
-                .collect();
-            Ok(ColumnarValue::Array(Arc::new(arr) as ArrayRef))
-        }
-        [
-            ColumnarValue::Array(expr_arg),
-            ColumnarValue::Array(bit_length_arg),
-        ] => {
-            let expr_iter = expr_arg.as_string::<i32>().iter();
-            let bit_length_iter = bit_length_arg.as_primitive::<Int32Type>().iter();
-            let arr: StringArray = expr_iter
-                .zip(bit_length_iter)
-                .map(|(expr, bit_length)| {
-                    match sha2([
-                        ColumnarValue::Scalar(ScalarValue::Utf8(Some(
-                            expr.unwrap().to_string(),
-                        ))),
-                        ColumnarValue::Scalar(ScalarValue::Int32(bit_length)),
-                    ])
-                    .unwrap()
-                    {
-                        ColumnarValue::Scalar(ScalarValue::Utf8(str)) => str,
-                        ColumnarValue::Array(arr) => arr
-                            .as_string::<i32>()
-                            .iter()
-                            .map(|str| str.unwrap().to_string())
-                            .next(), // first element
-                        _ => unreachable!(),
-                    }
-                })
-                .collect();
-            Ok(ColumnarValue::Array(Arc::new(arr) as ArrayRef))
-        }
-        _ => exec_err!("Unsupported argument types for sha2 function"),
-    }
+fn sha2_binary_impl<'a, BinaryArrType>(
+    values: &BinaryArrType,
+    bit_lengths: &Int32Array,
+) -> ArrayRef
+where
+    BinaryArrType: BinaryArrayType<'a>,
+{
+    let array = values
+        .iter()
+        .zip(bit_lengths.iter())
+        .map(|(value, bit_length)| match (value, bit_length) {
+            (Some(value), Some(224)) => {
+                let mut digest = sha2::Sha224::default();
+                digest.update(value);
+                Some(hex_encode(digest.finalize()))
+            }
+            (Some(value), Some(0 | 256)) => {
+                let mut digest = sha2::Sha256::default();
+                digest.update(value);
+                Some(hex_encode(digest.finalize()))
+            }
+            (Some(value), Some(384)) => {
+                let mut digest = sha2::Sha384::default();
+                digest.update(value);
+                Some(hex_encode(digest.finalize()))
+            }
+            (Some(value), Some(512)) => {
+                let mut digest = sha2::Sha512::default();
+                digest.update(value);
+                Some(hex_encode(digest.finalize()))
+            }
+            // Unknown bit-lengths go to null, same as in Spark
+            _ => None,
+        })
+        .collect::<StringArray>();
+    Arc::new(array)
 }
 
-fn compute_sha2(
-    bit_length_arg: i32,
-    expr_arg: &[ColumnarValue],
-) -> Result<ColumnarValue> {
-    match bit_length_arg {
-        0 | 256 => sha256(expr_arg),
-        224 => sha224(expr_arg),
-        384 => sha384(expr_arg),
-        512 => sha512(expr_arg),
-        _ => {
-            // Return null for unsupported bit lengths instead of error, because spark sha2 does not
-            // error out for this.
-            return Ok(ColumnarValue::Scalar(ScalarValue::Utf8(None)));
-        }
+fn hex_encode<T: AsRef<[u8]>>(data: T) -> String {
+    let mut s = String::with_capacity(data.as_ref().len() * 2);
+    for b in data.as_ref() {
+        // Writing to a string never errors, so we can unwrap here.
+        write!(&mut s, "{b:02x}").unwrap();
     }
-    .map(|hashed| spark_sha2_hex(&[hashed]).unwrap())
+    s
 }

datafusion/spark/src/function/hash/sha2.rs

@@ -75,3 +75,58 @@ SELECT sha2(expr, bit_length) FROM VALUES ('foo',0::INT), ('bar',224::INT), ('ba
 967004d25de4abc1bd6a7c9a216254a5ac0733e8ad96dc9f1ea0fad9619da7c32d654ec8ad8ba2f9b5728fed6633bd91
 8c6be9ed448a34883a13a13f4ead4aefa036b67dcda59020c01e57ea075ea8a4792d428f2c6fd0c09d1c49994d6c22789336e062188df29572ed07e7f9779c52
 NULL
+
+# All string types
+query T
+SELECT sha2(arrow_cast('foo', 'Utf8'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+query T
+SELECT sha2(arrow_cast('foo', 'LargeUtf8'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+query T
+SELECT sha2(arrow_cast('foo', 'Utf8View'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+# All binary types
+query T
+SELECT sha2(arrow_cast('foo', 'Binary'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+query T
+SELECT sha2(arrow_cast('foo', 'LargeBinary'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+query T
+SELECT sha2(arrow_cast('foo', 'BinaryView'), bit_length) FROM VALUES (224::INT), (256::INT) AS t(bit_length);
+----
+0808f64e60d58979fcb676c96ec938270dea42445aeefcd3a4e6f8db
+2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae
+
+
+# Null cases
+query T
+select sha2(null, 0);
+----
+NULL
+
+query T
+select sha2('a', null);
+----
+NULL
+
+query T
+select sha2('a', null::int);
+----
+NULL