Replace serde with serde_core when possible

arrow-integration-testing/Cargo.toml

@@ -40,7 +40,6 @@ arrow-integration-test = { path = "../arrow-integration-test", default-features
 clap = { version = "4", default-features = false, features = ["std", "derive", "help", "error-context", "usage"] }
 futures = { version = "0.3", default-features = false }
 prost = { version = "0.14.1", default-features = false }
-serde = { version = "1.0", default-features = false, features = ["rc", "derive"] }
 serde_json = { version = "1.0", default-features = false, features = ["std"] }
 tokio = { version = "1.0", default-features = false, features = [ "rt-multi-thread"] }
 tonic = { version = "0.14.1", default-features = false }

arrow-json/Cargo.toml

@@ -44,7 +44,7 @@ arrow-schema = { workspace = true }
 half = { version = "2.1", default-features = false }
 indexmap = { version = "2.0", default-features = false, features = ["std"] }
 num-traits = { version = "0.2.19", default-features = false, features = ["std"] }
-serde = { version = "1.0", default-features = false }
+serde_core = { version = "1.0", default-features = false }
 serde_json = { version = "1.0", default-features = false, features = ["std"] }
 chrono = { workspace = true }
 lexical-core = { version = "1.0", default-features = false}

arrow-json/src/reader/mod.rs

@@ -138,7 +138,7 @@ use std::io::BufRead;
 use std::sync::Arc;
 
 use chrono::Utc;
-use serde::Serialize;
+use serde_core::Serialize;
 
 use arrow_array::timezone::Tz;
 use arrow_array::types::*;
@@ -613,6 +613,8 @@ impl Decoder {
     /// ```
     ///
     /// Note: this ignores any batch size setting, and always decodes all rows
+    ///
+    /// [serde]: https://docs.rs/serde/latest/serde/
     pub fn serialize<S: Serialize>(&mut self, rows: &[S]) -> Result<(), ArrowError> {
         self.tape_decoder.serialize(rows)
     }

arrow-json/src/reader/serializer.rs

@@ -17,10 +17,10 @@
 
 use crate::reader::tape::TapeElement;
 use lexical_core::FormattedSize;
-use serde::ser::{
+use serde_core::ser::{
     Impossible, SerializeMap, SerializeSeq, SerializeStruct, SerializeTuple, SerializeTupleStruct,
 };
-use serde::{Serialize, Serializer};
+use serde_core::{Serialize, Serializer};
 
 #[derive(Debug)]
 pub struct SerializerError(String);
@@ -33,7 +33,7 @@ impl std::fmt::Display for SerializerError {
     }
 }
 
-impl serde::ser::Error for SerializerError {
+impl serde_core::ser::Error for SerializerError {
     fn custom<T>(msg: T) -> Self
     where
         T: std::fmt::Display,

arrow-json/src/reader/tape.rs

@@ -18,7 +18,7 @@
 use crate::reader::serializer::TapeSerializer;
 use arrow_schema::ArrowError;
 use memchr::memchr2;
-use serde::Serialize;
+use serde_core::Serialize;
 use std::fmt::Write;
 
 /// We decode JSON to a flattened tape representation,

arrow-json/src/writer/encoder.rs

@@ -26,7 +26,7 @@ use arrow_cast::display::{ArrayFormatter, FormatOptions};
 use arrow_schema::{ArrowError, DataType, FieldRef};
 use half::f16;
 use lexical_core::FormattedSize;
-use serde::Serializer;
+use serde_core::Serializer;
 
 /// Configuration options for the JSON encoder.
 #[derive(Debug, Clone, Default)]

arrow-schema/Cargo.toml

@@ -33,25 +33,30 @@ name = "arrow_schema"
 bench = false
 
 [dependencies]
-serde = { version = "1.0", default-features = false, features = [
-    "derive",
+serde_core = { version = "1.0", default-features = false, features = [
     "std",
     "rc",
 ], optional = true }
+serde = { version = "1.0", default-features = false, features = [
+    "derive",
+], optional = true }
 bitflags = { version = "2.0.0", default-features = false, optional = true }
 serde_json = { version = "1.0", optional = true }
 
 [features]
-canonical_extension_types = ["dep:serde", "dep:serde_json"]
+canonical_extension_types = ["dep:serde_core", "dep:serde_json"]
 # Enable ffi support
 ffi = ["bitflags"]
-serde = ["dep:serde"]
+serde = ["dep:serde_core", "dep:serde"]
 
 [package.metadata.docs.rs]
 all-features = true
 
 [dev-dependencies]
-bincode = { version = "2.0.1", default-features = false, features = ["std", "serde"] }
+bincode = { version = "2.0.1", default-features = false, features = [
+    "std",
+    "serde",
+] }
 criterion = { version = "0.5", default-features = false }
 insta = "1.43.1"
 

arrow-schema/src/extension/canonical/fixed_shape_tensor.rs

@@ -19,7 +19,10 @@
 //!
 //! <https://arrow.apache.org/docs/format/CanonicalExtensions.html#fixed-shape-tensor>
 
-use serde::{Deserialize, Serialize};
+use serde_core::de::{self, MapAccess, Visitor};
+use serde_core::ser::SerializeStruct;
+use serde_core::{Deserialize, Deserializer, Serialize, Serializer};
+use std::fmt;
 
 use crate::{ArrowError, DataType, extension::ExtensionType};
 
@@ -129,7 +132,7 @@ impl FixedShapeTensor {
 }
 
 /// Extension type metadata for [`FixedShapeTensor`].
-#[derive(Debug, Clone, PartialEq, Deserialize, Serialize)]
+#[derive(Debug, Clone, PartialEq)]
 pub struct FixedShapeTensorMetadata {
     /// The physical shape of the contained tensors.
     shape: Vec<usize>,
@@ -141,6 +144,143 @@ pub struct FixedShapeTensorMetadata {
     permutations: Option<Vec<usize>>,
 }
 
+impl Serialize for FixedShapeTensorMetadata {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let mut state = serializer.serialize_struct("FixedShapeTensorMetadata", 3)?;
+        state.serialize_field("shape", &self.shape)?;
+        state.serialize_field("dim_names", &self.dim_names)?;
+        state.serialize_field("permutations", &self.permutations)?;
+        state.end()
+    }
+}
+
+#[derive(Debug)]
+enum MetadataField {
+    Shape,
+    DimNames,
+    Permutations,
+}
+
+struct MetadataFieldVisitor;
+
+impl<'de> Visitor<'de> for MetadataFieldVisitor {
+    type Value = MetadataField;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("`shape`, `dim_names`, or `permutations`")
+    }
+
+    fn visit_str<E>(self, value: &str) -> Result<MetadataField, E>
+    where
+        E: de::Error,
+    {
+        match value {
+            "shape" => Ok(MetadataField::Shape),
+            "dim_names" => Ok(MetadataField::DimNames),
+            "permutations" => Ok(MetadataField::Permutations),
+            _ => Err(de::Error::unknown_field(
+                value,
+                &["shape", "dim_names", "permutations"],
+            )),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for MetadataField {
+    fn deserialize<D>(deserializer: D) -> Result<MetadataField, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_identifier(MetadataFieldVisitor)
+    }
+}
+
+struct FixedShapeTensorMetadataVisitor;
+
+impl<'de> Visitor<'de> for FixedShapeTensorMetadataVisitor {
+    type Value = FixedShapeTensorMetadata;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("struct FixedShapeTensorMetadata")
+    }
+
+    fn visit_seq<V>(self, mut seq: V) -> Result<FixedShapeTensorMetadata, V::Error>
+    where
+        V: de::SeqAccess<'de>,
+    {
+        let shape = seq
+            .next_element()?
+            .ok_or_else(|| de::Error::invalid_length(0, &self))?;
+        let dim_names = seq
+            .next_element()?
+            .ok_or_else(|| de::Error::invalid_length(1, &self))?;
+        let permutations = seq
+            .next_element()?
+            .ok_or_else(|| de::Error::invalid_length(2, &self))?;
+        Ok(FixedShapeTensorMetadata {
+            shape,
+            dim_names,
+            permutations,
+        })
+    }
+
+    fn visit_map<V>(self, mut map: V) -> Result<FixedShapeTensorMetadata, V::Error>
+    where
+        V: MapAccess<'de>,
+    {
+        let mut shape = None;
+        let mut dim_names = None;
+        let mut permutations = None;
+
+        while let Some(key) = map.next_key()? {
+            match key {
+                MetadataField::Shape => {
+                    if shape.is_some() {
+                        return Err(de::Error::duplicate_field("shape"));
+                    }
+                    shape = Some(map.next_value()?);
+                }
+                MetadataField::DimNames => {
+                    if dim_names.is_some() {
+                        return Err(de::Error::duplicate_field("dim_names"));
+                    }
+                    dim_names = Some(map.next_value()?);
+                }
+                MetadataField::Permutations => {
+                    if permutations.is_some() {
+                        return Err(de::Error::duplicate_field("permutations"));
+                    }
+                    permutations = Some(map.next_value()?);
+                }
+            }
+        }
+
+        let shape = shape.ok_or_else(|| de::Error::missing_field("shape"))?;
+
+        Ok(FixedShapeTensorMetadata {
+            shape,
+            dim_names,
+            permutations,
+        })
+    }
+}
+
+impl<'de> Deserialize<'de> for FixedShapeTensorMetadata {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_struct(
+            "FixedShapeTensorMetadata",
+            &["shape", "dim_names", "permutations"],
+            FixedShapeTensorMetadataVisitor,
+        )
+    }
+}
+
 impl FixedShapeTensorMetadata {
     /// Returns metadata for a fixed shape tensor extension type.
     ///
@@ -377,9 +517,8 @@ mod tests {
     }
 
     #[test]
-    #[should_panic(
-        expected = "FixedShapeTensor metadata deserialization failed: missing field `shape`"
-    )]
+    #[should_panic(expected = "FixedShapeTensor metadata deserialization failed: \
+        unknown field `not-shape`, expected one of `shape`, `dim_names`, `permutations`")]
     fn invalid_metadata() {
         let fixed_shape_tensor =
             FixedShapeTensor::try_new(DataType::Float32, [100, 200, 500], None, None).unwrap();

arrow-schema/src/extension/canonical/json.rs

@@ -19,7 +19,10 @@
 //!
 //! <https://arrow.apache.org/docs/format/CanonicalExtensions.html#json>
 
-use serde::{Deserialize, Serialize};
+use serde_core::de::{self, MapAccess, Visitor};
+use serde_core::ser::SerializeStruct;
+use serde_core::{Deserialize, Deserializer, Serialize, Serializer};
+use std::fmt;
 
 use crate::{ArrowError, DataType, extension::ExtensionType};
 
@@ -42,10 +45,78 @@ use crate::{ArrowError, DataType, extension::ExtensionType};
 pub struct Json(JsonMetadata);
 
 /// Empty object
-#[derive(Debug, Clone, Copy, PartialEq, Deserialize, Serialize)]
-#[serde(deny_unknown_fields)]
+#[derive(Debug, Clone, Copy, PartialEq)]
 struct Empty {}
 
+impl Serialize for Empty {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let state = serializer.serialize_struct("Empty", 0)?;
+        state.end()
+    }
+}
+
+struct EmptyVisitor;
+
+impl<'de> Visitor<'de> for EmptyVisitor {
+    type Value = Empty;
+
+    fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+        formatter.write_str("struct Empty")
+    }
+
+    fn visit_seq<A>(self, mut _seq: A) -> Result<Self::Value, A::Error>
+    where
+        A: de::SeqAccess<'de>,
+    {
+        Ok(Empty {})
+    }
+
+    fn visit_map<V>(self, mut map: V) -> Result<Empty, V::Error>
+    where
+        V: MapAccess<'de>,
+    {
+        if let Some(key) = map.next_key::<String>()? {
+            return Err(de::Error::unknown_field(&key, EMPTY_FIELDS));
+        }
+        Ok(Empty {})
+    }
+
+    fn visit_u64<E>(self, _v: u64) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Err(de::Error::unknown_field("", EMPTY_FIELDS))
+    }
+
+    fn visit_str<E>(self, _v: &str) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Err(de::Error::unknown_field("", EMPTY_FIELDS))
+    }
+
+    fn visit_bytes<E>(self, _v: &[u8]) -> Result<Self::Value, E>
+    where
+        E: de::Error,
+    {
+        Err(de::Error::unknown_field("", EMPTY_FIELDS))
+    }
+}
+
+static EMPTY_FIELDS: &[&str] = &[];
+
+impl<'de> Deserialize<'de> for Empty {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        deserializer.deserialize_struct("Empty", EMPTY_FIELDS, EmptyVisitor)
+    }
+}
+
 /// Extension type metadata for [`Json`].
 #[derive(Debug, Default, Clone, PartialEq)]
 pub struct JsonMetadata(Option<Empty>);