partial serde deserialization

src/bipack_source.rs

@@ -12,7 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::error::Error;
 use std::fmt::{Display, Formatter};
 use std::string::FromUtf8Error;
 use crate::bipack_source::BipackError::NoDataError;
@@ -27,21 +26,21 @@ pub enum BipackError {
     BadEncoding(FromUtf8Error),
 }
 
+impl std::error::Error for BipackError {}
+
 impl Display for BipackError {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         write!(f, "{:?}", self)
     }
 }
 
-impl Error for BipackError {}
-
-
 /// Data source compatible with mp_bintools serialization. It supports
 /// fixed-size integers in right order and varint ans smartint encodings
 /// separately. There is out of the box implementation for [`Vec<u8>`], and
 /// it is easy to implements your own.
 ///
-/// To implement source for other type, implement just [BipackSource::get_u8] or mayve also
+/// To implement source for other type, implement just [BipackSource::get_u8],
+/// [BipackSource::eof] or mayve also
 /// [BipackSource::get_fixed_bytes] for effectiveness.
 ///
 /// Unlike the [crate::bipack_sink::BipackSink] the source is returning errors. This is because
@@ -50,6 +49,10 @@ impl Error for BipackError {}
 pub trait BipackSource {
     fn get_u8(self: &mut Self) -> Result<u8>;
 
+    /// Tribute to the tradition. End Of File, if true, there is no unread data left
+    /// in the source.
+    fn eof(self: &Self) -> bool;
+
     fn get_u16(self: &mut Self) -> Result<u16> {
         Ok(((self.get_u8()? as u16) << 8) + (self.get_u8()? as u16))
     }
@@ -179,6 +182,38 @@ impl<'x> BipackSource for SliceSource<'x> {
             Ok(result)
         }
     }
+
+    fn eof(self: &Self) -> bool {
+        self.data.len() >= self.position
+    }
+}
+
+pub struct VecSource {
+    data: Vec<u8>,
+    position: usize,
+}
+
+impl VecSource {
+    pub fn from(src: Vec<u8>) -> VecSource {
+        VecSource { data: src, position: 0 }
+    }
+}
+
+impl BipackSource for VecSource {
+    fn get_u8(self: &mut Self) -> Result<u8> {
+        if self.position >= self.data.len() {
+            Err(NoDataError)
+        } else {
+            let result = self.data[self.position];
+            self.position += 1;
+            Ok(result)
+        }
+    }
+
+    fn eof(self: &Self) -> bool {
+        self.data.len() <= self.position
+    }
 }
 
 
+

src/de.rs

@@ -0,0 +1,258 @@
+use serde::de::{
+    self, DeserializeSeed, MapAccess, SeqAccess,
+    Visitor,
+};
+use serde::{Serialize};
+use serde::Deserialize;
+
+use crate::bipack_source::{BipackSource, VecSource};
+use crate::error::{Error, Result};
+use crate::ser::to_bytes;
+use crate::tools::to_dump;
+
+pub struct Deserializer {
+    // This string starts with the input data and characters are truncated off
+    // the beginning as data is parsed.
+    input: VecSource,
+}
+
+pub fn from_bytes<'de,T: Deserialize<'de>>(source: Vec<u8>) -> Result<T> {
+    let mut des = Deserializer { input: VecSource::from(source)};
+    T::deserialize(&mut des)
+}
+
+impl<'de, 'a> de::Deserializer<'de> for &'a mut Deserializer {
+    type Error = Error;
+
+    fn deserialize_any<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        Err(Error::NotPossible)
+    }
+
+    fn deserialize_bool<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_bool(if self.input.get_u8()? == 0 { false } else { true } )
+    }
+
+    fn deserialize_i8<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_i8(self.input.get_i8()?)
+    }
+
+    fn deserialize_i16<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_i16(self.input.get_signed()? as i16)
+    }
+
+    fn deserialize_i32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_i32(self.input.get_signed()? as i32)
+    }
+
+    fn deserialize_i64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_i64(self.input.get_signed()?)
+    }
+
+    fn deserialize_u8<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_u8(self.input.get_u8()?)
+    }
+
+    fn deserialize_u16<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_u16(self.input.get_unsigned()? as u16)
+    }
+
+    fn deserialize_u32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_u32(self.input.get_unsigned()? as u32)
+    }
+
+    fn deserialize_u64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_u64(self.input.get_unsigned()?)
+    }
+
+    fn deserialize_f32<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        Err(Error::NotImplemented)
+    }
+
+    fn deserialize_f64<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        Err(Error::NotImplemented)
+    }
+
+    fn deserialize_char<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        let ch = self.input.get_str()?;
+        if ch.len() != 1 {
+            Err(Error::BadFormat(format!("Char length is {}, should be 1 {:?}", ch.len(), ch)))
+        }
+        else {
+            visitor.visit_char(ch.chars().next().unwrap())
+        }
+    }
+
+    fn deserialize_str<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_string( self.input.get_str()?)
+    }
+
+    fn deserialize_string<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_string(self.input.get_str()?)
+    }
+
+    fn deserialize_bytes<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_byte_buf(self.input.get_var_bytes()?)
+    }
+
+    fn deserialize_byte_buf<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_byte_buf(self.input.get_var_bytes()?)
+    }
+
+    fn deserialize_option<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        let marker = self.input.get_u8()?;
+        if marker == 0 {
+            visitor.visit_none()
+        } else {
+            visitor.visit_some(self)
+        }
+    }
+
+    fn deserialize_unit<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_unit()
+    }
+
+    fn deserialize_unit_struct<V>(self, name: &'static str, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        self.deserialize_unit(visitor)
+    }
+
+    fn deserialize_newtype_struct<V>(self, name: &'static str, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_newtype_struct(self)
+    }
+
+    fn deserialize_seq<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        let size = self.input.get_unsigned()? as usize;
+        visitor.visit_seq(SimpleSeq::new(self, size))
+    }
+
+    fn deserialize_tuple<V>(self, len: usize, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_seq(SimpleSeq::new(self, len))
+    }
+
+    fn deserialize_tuple_struct<V>(self, name: &'static str, len: usize, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_seq(SimpleSeq::new(self, len))
+    }
+
+    fn deserialize_map<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        let size = self.input.get_unsigned()?;
+        visitor.visit_map(SimpleMap { de: self, size: size as usize} )
+    }
+
+    fn deserialize_struct<V>(self, name: &'static str, fields: &'static [&'static str], visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        visitor.visit_seq(SimpleSeq::new(self, fields.len() ))
+    }
+
+    fn deserialize_enum<V>(self, name: &'static str, variants: &'static [&'static str], visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        todo!()
+    }
+
+    fn deserialize_identifier<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        Err(Error::NotPossible)
+    }
+
+    fn deserialize_ignored_any<V>(self, visitor: V) -> std::result::Result<V::Value, Self::Error> where V: Visitor<'de> {
+        Err(Error::NotPossible)
+    }
+
+    fn is_human_readable(&self) -> bool {
+        false
+    }
+}
+
+struct SimpleSeq<'a> {
+    de: &'a mut Deserializer,
+    size: usize,
+}
+
+impl<'a> SimpleSeq<'a> {
+    fn new(de: &'a mut Deserializer,size: usize) -> Self {
+        SimpleSeq {
+            de,
+            size: size,
+        }
+    }
+}
+
+// `SeqAccess` is provided to the `Visitor` to give it the ability to iterate
+// through elements of the sequence.
+impl<'de, 'a> SeqAccess<'de> for SimpleSeq<'a> {
+    type Error = Error;
+
+    fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>>
+        where
+            T: DeserializeSeed<'de>,
+    {
+        if self.size < 1 {
+            return Ok(None);
+        }
+        self.size -= 1;
+        seed.deserialize(&mut *self.de).map(Some)
+    }
+}
+
+
+struct SimpleMap<'a> {
+    de: &'a mut Deserializer,
+    size: usize,
+}
+
+impl<'de, 'a> MapAccess<'de> for SimpleMap<'a> {
+    type Error = Error;
+
+    fn next_key_seed<K>(&mut self, seed: K) -> std::result::Result<Option<K::Value>, Self::Error> where K: DeserializeSeed<'de> {
+        if self.size < 1 {
+            Ok(None)
+        }
+        else {
+            self.size -= 1;
+            seed.deserialize(&mut *self.de).map(Some)
+        }
+    }
+
+    fn next_value_seed<V>(&mut self, seed: V) -> std::result::Result<V::Value, Self::Error> where V: DeserializeSeed<'de> {
+        seed.deserialize(&mut *self.de)
+    }
+}
+
+
+#[test]
+fn test_ints() -> Result<()> {
+    // #[derive(Deserialize, PartialEq, Debug)]
+    // struct Test {
+    //     int: u32,
+    //     seq: Vec<String>,
+    // }
+
+    let b = vec![7];
+    assert_eq!( 7u8, from_bytes(vec![7u8])?);
+
+
+    // let j = r#"{"int":1,"seq":["a","b"]}"#;
+    // let expected = Test {
+    //     int: 1,
+    //     seq: vec!["a".to_owned(), "b".to_owned()],
+    // };
+    // assert_eq!(expected, from_str(j).unwrap());
+    Ok(())
+}
+
+#[test]
+fn test_struct_de() -> Result<()> {
+    #[derive(Serialize, Deserialize, PartialEq, Debug)]
+    struct Test {
+        int: u32,
+        seq: Vec<String>,
+    }
+    let expected = Test {
+        int: 1,
+        seq: vec!["a".to_owned(), "b".to_owned()],
+    };
+
+    let packed = to_bytes(&expected)?;
+    println!("::{}", to_dump(&packed));
+    let unpacked: Test = from_bytes(packed)?;
+    println!("::{:?}", unpacked);
+    Ok(())
+
+    // let j = r#"{"int":1,"seq":["a","b"]}"#;
+    // assert_eq!(expected, from_str(j).unwrap());
+}

src/error.rs

@@ -1,14 +1,20 @@
 use std;
 use std::fmt::{self, Display};
 use serde::{de, ser};
+use crate::bipack_source::BipackError;
 
 pub type Result<T> = std::result::Result<T, Error>;
 
 #[derive(Debug)]
 pub enum Error {
     Message(String),
+    BadFormat(String),
     Eof,
+    ExtraBytes,
     BadEncoding,
+    NotSupported,
+    NotImplemented,
+    NotPossible
 }
 
 impl Display for Error {
@@ -33,3 +39,13 @@ impl de::Error for Error {
         Error::Message(msg.to_string())
     }
 }
+
+impl From<BipackError> for Error {
+    fn from(value: BipackError) -> Self {
+        match &value {
+            BipackError::NoDataError => Error::Eof,
+            BipackError::BadEncoding(_) => Error::BadEncoding,
+            // other => Error::Message(format!("BiPack error: {}", value))
+        }
+    }
+}

src/lib.rs

@@ -120,6 +120,7 @@ pub mod tools;
 pub mod bipack;
 mod error;
 mod ser;
+mod de;
 
 #[cfg(test)]
 mod tests {

src/ser.rs

@@ -1,8 +1,11 @@
-use serde::{ser, Serialize};
-use crate::bipack_sink::{BipackSink, IntoU64};
+use std::string::FromUtf8Error;
 
+use serde::{ser, Serialize};
+
+use crate::bipack_sink::{BipackSink, IntoU64};
+use crate::bipack_source::{BipackError, BipackSource, SliceSource};
 use crate::error::{Error, Result};
-use crate::tools::to_dump;
+use crate::tools::{to_dump, to_hex};
 
 pub struct Serializer {
     // This string starts empty and JSON is appended as values are serialized.
@@ -56,11 +59,11 @@ impl<'a> ser::Serializer for &'a mut Serializer {
         Ok(())
     }
     fn serialize_u16(self, v: u16) -> Result<()> {
-        self.output.put_u64(v.into());
+        self.serialize_u64(v.into_u64())?;
         Ok(())
     }
     fn serialize_u32(self, v: u32) -> Result<()> {
-        self.output.put_u64(v.into_u64());
+        self.serialize_u64(v.into())?;
         Ok(())
     }
     fn serialize_u64(self, v: u64) -> Result<()> {
@@ -93,7 +96,7 @@ impl<'a> ser::Serializer for &'a mut Serializer {
     }
 
     fn serialize_none(self) -> Result<()> {
-        self.serialize_u8(0);
+        self.serialize_u8(0)?;
         Ok(())
     }
 
@@ -101,12 +104,11 @@ impl<'a> ser::Serializer for &'a mut Serializer {
         where
             T: ?Sized + Serialize,
     {
-        self.serialize_u8(1);
+        self.serialize_u8(1)?;
         value.serialize(self)
     }
 
     fn serialize_unit(self) -> Result<()> {
-        self.output.put_u8(0);
         Ok(())
     }
 
@@ -144,10 +146,11 @@ impl<'a> ser::Serializer for &'a mut Serializer {
         where
             T: ?Sized + Serialize,
     {
-        self.serialize_str(_name);
-        self.serialize_u32(_variant_index)
+        self.serialize_u32(_variant_index)?;
+        value.serialize(self)
     }
 
+    /// We expect it to use with vairable-length arrays...
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
         self.output.put_unsigned(_len.unwrap_or(0));
         Ok(self)
@@ -172,7 +175,7 @@ impl<'a> ser::Serializer for &'a mut Serializer {
         variant: &'static str,
         _len: usize,
     ) -> Result<Self::SerializeTupleVariant> {
-        variant.serialize(&mut *self)?;
+        _variant_index.serialize(&mut *self)?;
         Ok(self)
     }
 
@@ -186,7 +189,8 @@ impl<'a> ser::Serializer for &'a mut Serializer {
         _name: &'static str,
         len: usize,
     ) -> Result<Self::SerializeStruct> {
-        self.serialize_map(Some(len))
+        // self.serialize_map(Some(len))
+        Ok(self)
     }
     fn serialize_struct_variant(
         self,
@@ -312,7 +316,6 @@ impl<'a> ser::SerializeStruct for &'a mut Serializer {
         where
             T: ?Sized + Serialize,
     {
-        key.serialize(&mut **self)?;
         value.serialize(&mut **self)
     }
 
@@ -329,7 +332,6 @@ impl<'a> ser::SerializeStructVariant for &'a mut Serializer {
         where
             T: ?Sized + Serialize,
     {
-        key.serialize(&mut **self)?;
         value.serialize(&mut **self)
     }
 
@@ -339,7 +341,7 @@ impl<'a> ser::SerializeStructVariant for &'a mut Serializer {
 }
 
 #[test]
-fn test_struct() {
+fn test_struct() -> std::result::Result<(), BipackError> {
     #[derive(Serialize)]
     struct Test {
         int: u32,
@@ -347,26 +349,43 @@ fn test_struct() {
     }
 
     let test = Test {
-        int: 1,
+        int: 17,
         seq: vec!["a", "b"],
     };
-    // let expected = r#"{"int":1,"seq":["a","b"]}"#;
-    // assert_eq!(to_string(&test).unwrap(), expected);
     let x = to_bytes(&test).unwrap();
     println!("!:\n{}", to_dump(&x));
+    // let y = x.clone();
+    // let z = x.clone();
+    let mut src = SliceSource::from(&x);
+    assert_eq!(test.int, src.get_unsigned()? as u32);
+    assert_eq!(test.seq.len(), src.get_unsigned()? as usize);
+    assert_eq!(test.seq[0], src.get_str()?);
+    assert_eq!(test.seq[1], src.get_str()?);
+    Ok(())
 }
 
-// #[test]
-// fn test_enum() {
-//     #[derive(Serialize)]
-//     enum E {
-//         Unit,
-//         Newtype(u32),
-//         Tuple(u32, u32),
-//         Struct { a: u32 },
-//     }
-//
-//     let u = E::Unit;
+#[test]
+fn test_enum() -> std::result::Result<(), FromUtf8Error> {
+    #[derive(Serialize)]
+    enum E {
+        Unit,
+        Unit2,
+        Newtype(u32),
+        Tuple(u32, u32),
+        Struct { a: u32 },
+    }
+
+    let u = E::Unit;
+    println!("u:{}",to_dump(to_bytes(&u).unwrap().as_slice()));
+    assert_eq!("00",to_hex(to_bytes(&u).unwrap())?);
+    let u2 = E::Unit2;
+    println!("u:{}",to_dump(to_bytes(&u2).unwrap().as_slice()));
+    let nt = E::Newtype(17);
+    println!("u:{}",to_dump(to_bytes(&nt).unwrap().as_slice()));
+    assert_eq!("08 44",to_hex(to_bytes(&nt).unwrap())?);
+    let t = E::Tuple(7,17);
+    println!("u:{}",to_dump(to_bytes(&t).unwrap().as_slice()));
+    assert_eq!("0c 1c 44",to_hex(to_bytes(&t).unwrap())?);
     // let expected = r#""Unit""#;
     // assert_eq!(to_string(&u).unwrap(), expected);
     //
@@ -381,4 +400,5 @@ fn test_struct() {
     // let s = E::Struct { a: 1 };
     // let expected = r#"{"Struct":{"a":1}}"#;
     // assert_eq!(to_string(&s).unwrap(), expected);
-// }
+    Ok(())
+}

src/tools.rs

@@ -37,6 +37,8 @@ impl StringBuilder {
     }
 
     fn new() -> StringBuilder { StringBuilder(Vec::new()) }
+
+    fn len(self: &Self) -> usize { self.0.len() }
 }
 
 
@@ -83,3 +85,11 @@ pub fn to_dump(data: &[u8]) -> String {
     result.string().unwrap()
 }
 
+pub fn to_hex<T: AsRef<[u8]>>(source: T) -> Result<String,FromUtf8Error> {
+    let mut result = StringBuilder::new();
+    for b in source.as_ref() {
+        if result.len() != 0 { result.append( " ") }
+        result.append(format!("{:02x}", b))
+    }
+    result.string()
+}