libsql/
de.rs

1//! Deserialization utilities.
2
3use crate::{Row, Value};
4use serde::de::{value::Error as DeError, Error, IntoDeserializer, MapAccess, Visitor};
5use serde::{Deserialize, Deserializer};
6
7struct RowDeserializer<'de> {
8    row: &'de Row,
9}
10
11impl<'de> Deserializer<'de> for RowDeserializer<'de> {
12    type Error = DeError;
13
14    fn deserialize_any<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
15    where
16        V: Visitor<'de>,
17    {
18        Err(DeError::custom("Expects a struct"))
19    }
20
21    fn deserialize_struct<V>(
22        self,
23        _name: &'static str,
24        _fields: &'static [&'static str],
25        visitor: V,
26    ) -> Result<V::Value, Self::Error>
27    where
28        V: Visitor<'de>,
29    {
30        struct RowMapAccess<'a> {
31            row: &'a Row,
32            idx: std::ops::Range<usize>,
33            value: Option<Value>,
34        }
35
36        impl<'de> MapAccess<'de> for RowMapAccess<'de> {
37            type Error = DeError;
38
39            fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error>
40            where
41                K: serde::de::DeserializeSeed<'de>,
42            {
43                match self.idx.next() {
44                    None => Ok(None),
45                    Some(i) => {
46                        let value = self.row.get_value(i as i32).map_err(DeError::custom)?;
47                        self.value = Some(value);
48                        self.row
49                            .column_name(i as i32)
50                            .map(|name| seed.deserialize(name.into_deserializer()))
51                            .transpose()
52                    }
53                }
54            }
55
56            fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error>
57            where
58                V: serde::de::DeserializeSeed<'de>,
59            {
60                let value = self
61                    .value
62                    .take()
63                    .ok_or(DeError::custom("Expects a value but row is exhausted"))?;
64
65                seed.deserialize(value.into_deserializer())
66            }
67        }
68
69        visitor.visit_map(RowMapAccess {
70            row: self.row,
71            idx: 0..(self.row.inner.column_count() as usize),
72            value: None,
73        })
74    }
75
76    serde::forward_to_deserialize_any! {
77        bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
78        bytes byte_buf option unit unit_struct newtype_struct seq tuple
79        tuple_struct map enum identifier ignored_any
80    }
81}
82
83pub fn from_row<'de, T: Deserialize<'de>>(row: &'de Row) -> Result<T, DeError> {
84    let de = RowDeserializer { row };
85    T::deserialize(de)
86}
libsql/de.rs

libsql/
de.rs
