qubit_metadata/
from_metadata_value.rs

1/*******************************************************************************
2 *
3 *    Copyright (c) 2025 - 2026 Haixing Hu.
4 *
5 *    SPDX-License-Identifier: Apache-2.0
6 *
7 *    Licensed under the Apache License, Version 2.0.
8 *
9 ******************************************************************************/
10//! Provides conversion from metadata values into supported Rust values.
11
12use std::collections::HashMap;
13use std::time::Duration;
14
15use bigdecimal::BigDecimal;
16use chrono::{
17    DateTime,
18    NaiveDate,
19    NaiveDateTime,
20    NaiveTime,
21    Utc,
22};
23use qubit_value::{
24    Value,
25    ValueResult,
26};
27use url::Url;
28
29/// Converts metadata backing [`Value`] instances into supported Rust types.
30///
31/// This trait is implemented for the same concrete output types accepted by
32/// [`Value::to`]. It keeps metadata accessors generic without depending on
33/// `qubit-value` internal conversion traits.
34pub trait FromMetadataValue: Sized {
35    /// Converts `value` into `Self`.
36    ///
37    /// # Errors
38    ///
39    /// Returns a [`qubit_value::ValueError`] when the stored value is absent,
40    /// unsupported, or cannot be converted to `Self`.
41    fn from_metadata_value(value: &Value) -> ValueResult<Self>;
42}
43
44macro_rules! impl_from_metadata_value {
45    ($($type:ty),+ $(,)?) => {
46        $(
47            impl FromMetadataValue for $type {
48                #[inline]
49                fn from_metadata_value(value: &Value) -> ValueResult<Self> {
50                    value.to::<$type>()
51                }
52            }
53        )+
54    };
55}
56
57impl_from_metadata_value!(
58    bool,
59    char,
60    i8,
61    i16,
62    i32,
63    i64,
64    i128,
65    u8,
66    u16,
67    u32,
68    u64,
69    u128,
70    f32,
71    f64,
72    String,
73    NaiveDate,
74    NaiveTime,
75    NaiveDateTime,
76    DateTime<Utc>,
77    num_bigint::BigInt,
78    BigDecimal,
79    isize,
80    usize,
81    Duration,
82    Url,
83    HashMap<String, String>,
84    serde_json::Value,
85);
qubit_metadata/from_metadata_value.rs

qubit_metadata/
from_metadata_value.rs
