crud_api_endpoint/
types.rs

1use darling::{ast::NestedMeta, FromMeta};
2use serde::{Deserialize, Serialize};
3
4/// Wrapper for Vec<String> to implements FromMeta
5#[derive(Debug, Clone, Deserialize, Serialize)]
6pub struct VecStringWrapper {
7  pub v: Vec<String>,
8  pub c: Vec<char>, // also stores the first char of each string
9}
10
11impl From<Vec<String>> for VecStringWrapper {
12  fn from(v: Vec<String>) -> Self {
13    VecStringWrapper {
14      c: v
15        .iter()
16        .map(|s| s.chars().next().unwrap())
17        .collect::<Vec<char>>(),
18      v,
19    }
20  }
21}
22impl From<VecStringWrapper> for Vec<String> {
23  fn from(val: VecStringWrapper) -> Self {
24    val.v
25  }
26}
27
28impl FromMeta for VecStringWrapper {
29  fn from_nested_meta(item: &NestedMeta) -> darling::Result<Self> {
30    (match *item {
31      NestedMeta::Lit(ref lit) => Self::from_value(lit),
32      NestedMeta::Meta(ref mi) => Self::from_meta(mi),
33    })
34    .map_err(|e| e.with_span(item))
35  }
36
37  fn from_meta(item: &syn::Meta) -> darling::Result<Self> {
38    (match *item {
39      syn::Meta::Path(_) => Self::from_word(),
40      syn::Meta::List(ref value) => {
41        Self::from_list(&NestedMeta::parse_meta_list(value.tokens.clone())?[..])
42      }
43      syn::Meta::NameValue(ref value) => Self::from_expr(&value.value),
44    })
45    .map_err(|e| e.with_span(item))
46  }
47
48  fn from_none() -> Option<Self> {
49    None
50  }
51
52  fn from_word() -> darling::Result<Self> {
53    Err(darling::Error::unsupported_format("word"))
54  }
55
56  fn from_list(_items: &[NestedMeta]) -> darling::Result<Self> {
57    Err(darling::Error::unsupported_format("list"))
58  }
59
60  fn from_value(value: &syn::Lit) -> darling::Result<Self> {
61    (match *value {
62      syn::Lit::Bool(ref b) => Self::from_bool(b.value),
63      syn::Lit::Str(ref s) => Self::from_string(&s.value()),
64      syn::Lit::Char(ref ch) => Self::from_char(ch.value()),
65      _ => Err(darling::Error::unexpected_lit_type(value)),
66    })
67    .map_err(|e| e.with_span(value))
68  }
69
70  fn from_expr(expr: &syn::Expr) -> darling::Result<Self> {
71    match *expr {
72      syn::Expr::Lit(ref lit) => Self::from_value(&lit.lit),
73      syn::Expr::Group(ref group) => Self::from_expr(&group.expr),
74      _ => Err(darling::Error::unexpected_expr_type(expr)),
75    }
76    .map_err(|e| e.with_span(expr))
77  }
78
79  fn from_char(_value: char) -> darling::Result<Self> {
80    Err(darling::Error::unexpected_type("char"))
81  }
82
83  fn from_string(value: &str) -> darling::Result<Self> {
84    Ok(VecStringWrapper {
85      v: value
86        .split(',')
87        .map(|s| s.to_string())
88        .collect::<Vec<String>>(),
89      c: value
90        .split(',')
91        .map(|s| s.chars().next().unwrap_or_default())
92        .collect::<Vec<char>>(),
93    })
94  }
95
96  fn from_bool(_value: bool) -> darling::Result<Self> {
97    Err(darling::Error::unexpected_type("bool"))
98  }
99}