Struct Deserializer

pub struct Deserializer<R> { /* private fields */ }

A Bencode Deserializer for types which implement Deserialize.

Implementations

impl<'a, R> Deserializer<R>

where R: Read<'a>,

pub fn new(read: R) -> Self

Constructs a Deserializer from a readable source.

pub fn byte_offset(&self) -> usize

Returns the byte offset in the underlying readable source.

For most use cases, the entire source should be consumed with no trailing data (e.g. a metainfo file should not have extra data after the bencoded data).

If there is expected trailing data, then it may be helpful to know how much data was read.

Example

use serde::Deserialize as _;
use bt_bencode::Deserializer;

let bytes: &[u8] = b"4:spameggs";
let mut de = Deserializer::from_slice(bytes);
let value: &str = <&str>::deserialize(&mut de)?;
assert_eq!(value, "spam");

// Do not call `de.end()` which checks for trailing data

assert_eq!(de.byte_offset(), 6);
assert_eq!(b"eggs", &bytes[de.byte_offset()..]);

pub fn end(&mut self) -> Result<()>

Should be called after a value from the source is deserialized to validate that the entire source was read.

If trailing data is expected, do not call this method. It may be beneficial to know how much data was read. See Deserializer::byte_offset().

Errors

An error is returned if there are unconsumed bytes in the readable source.

impl<R> Deserializer<IoRead<R>>

where R: Read,

pub fn from_reader(reader: R) -> Self

Constructs a Deserializer from an std::io::Read source.

impl<'a> Deserializer<SliceRead<'a>>

pub fn from_slice(bytes: &'a [u8]) -> Self

Constructs a Deserializer from a &[u8].

Trait Implementations

impl<R: Debug> Debug for Deserializer<R>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de, R: Read<'de>> Deserializer<'de> for &mut Deserializer<R>

type Error = Error

The error type that can be returned if some error occurs during deserialization.

fn deserialize_any<V>(self, visitor: V) -> Result<V::Value>

where V: Visitor<'de>,

Require the Deserializer to figure out how to drive the visitor based on what data type is in the input.

fn deserialize_bool<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a bool value.

fn deserialize_i8<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an i8 value.

fn deserialize_i16<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an i16 value.

fn deserialize_i32<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an i32 value.

fn deserialize_i64<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an i64 value.

fn deserialize_i128<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an i128 value.

fn deserialize_u8<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a u8 value.

fn deserialize_u16<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a u16 value.

fn deserialize_u32<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a u32 value.

fn deserialize_u64<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a u64 value.

fn deserialize_u128<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an u128 value.

fn deserialize_f32<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a f32 value.

fn deserialize_f64<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a f64 value.

fn deserialize_unit<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a unit value.

fn deserialize_unit_struct<V>( self, name: &'static str, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a unit struct with a particular name.

fn deserialize_char<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a char value.

fn deserialize_str<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a string value and does not benefit from taking ownership of buffered data owned by the Deserializer.

fn deserialize_string<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a string value and would benefit from taking ownership of buffered data owned by the Deserializer.

fn deserialize_seq<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a sequence of values.

fn deserialize_tuple<V>( self, len: usize, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a sequence of values and knows how many values there are without looking at the serialized data.

fn deserialize_tuple_struct<V>( self, name: &'static str, len: usize, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a tuple struct with a particular name and number of fields.

fn deserialize_map<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a map of key-value pairs.

fn deserialize_struct<V>( self, name: &'static str, fields: &'static [&'static str], visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a struct with a particular name and fields.

fn deserialize_enum<V>( self, name: &'static str, variants: &'static [&'static str], visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an enum value with a particular name and possible variants.

fn deserialize_identifier<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting the name of a struct field or the discriminant of an enum variant.

fn deserialize_ignored_any<V>( self, visitor: V, ) -> Result<V::Value, <Self as Deserializer<'de>>::Error>

where V: Visitor<'de>,

Hint that the Deserialize type needs to deserialize a value whose type doesn’t matter because it is ignored.

fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a byte array and does not benefit from taking ownership of buffered data owned by the Deserializer.

fn deserialize_byte_buf<V>(self, visitor: V) -> Result<V::Value>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a byte array and would benefit from taking ownership of buffered data owned by the Deserializer.

fn deserialize_option<V>(self, visitor: V) -> Result<V::Value>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting an optional value.

fn deserialize_newtype_struct<V>( self, _name: &'static str, visitor: V, ) -> Result<V::Value>

where V: Visitor<'de>,

Hint that the Deserialize type is expecting a newtype struct with a particular name.

fn is_human_readable(&self) -> bool

Determine whether Deserialize implementations should expect to deserialize their human-readable form.