-
Notifications
You must be signed in to change notification settings - Fork 84
/
lib.rs
134 lines (119 loc) · 3.67 KB
/
lib.rs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
#![recursion_limit = "1024"]
extern crate proc_macro;
#[macro_use]
extern crate quote;
extern crate syn;
extern crate walkdir;
use proc_macro::TokenStream;
use quote::Tokens;
use std::path::Path;
use syn::*;
mod utils;
#[cfg(all(debug_assertions, not(feature = "debug-embed")))]
fn generate_assets(ident: &syn::Ident, folder_path: String) -> quote::Tokens {
quote!{
impl #ident {
pub fn get(file_path: &str) -> Option<impl AsRef<[u8]>> {
use std::fs::File;
use std::io::Read;
use std::path::Path;
let file_path = Path::new(#folder_path).join(file_path);
let mut file = match File::open(file_path) {
Ok(mut file) => file,
Err(_e) => {
return None
}
};
let mut data: Vec<u8> = Vec::new();
match file.read_to_end(&mut data) {
Ok(_) => Some(data),
Err(_e) => {
return None
}
}
}
pub fn iter() -> impl Iterator<Item = impl AsRef<str>> {
use std::path::Path;
use rust_embed::utils::get_files;
get_files(String::from(#folder_path)).map(|e| e.rel_path)
}
}
}
}
#[cfg(any(not(debug_assertions), feature = "debug-embed"))]
fn generate_assets(ident: &syn::Ident, folder_path: String) -> quote::Tokens {
use utils::{get_files, FileEntry};
let mut match_values = Vec::<Tokens>::new();
let mut list_values = Vec::<String>::new();
for FileEntry { rel_path, full_canonical_path } in get_files(folder_path) {
match_values.push(quote!{
#rel_path => Some(&include_bytes!(#full_canonical_path)[..]),
});
list_values.push(rel_path);
}
let array_len = list_values.len();
quote!{
impl #ident {
pub fn get(file_path: &str) -> Option<impl AsRef<[u8]>> {
match file_path {
#(#match_values)*
_ => None,
}
}
pub fn iter() -> impl Iterator<Item = impl AsRef<str>> {
static items: [&str; #array_len] = [#(#list_values),*];
items.iter()
}
}
}
}
fn help() {
panic!("#[derive(RustEmbed)] should contain one attribute like this #[folder = \"examples/public/\"]");
}
fn impl_rust_embed(ast: &syn::DeriveInput) -> Tokens {
match ast.body {
Body::Enum(_) => help(),
Body::Struct(ref data) => match data {
&VariantData::Struct(_) => help(),
_ => {}
},
};
let ident = &ast.ident;
if ast.attrs.len() == 0 || ast.attrs.len() > 1 {
help();
}
let value = &ast.attrs[0].value;
let literal_value = match value {
&MetaItem::NameValue(ref attr_name, ref value) => {
if attr_name == "folder" {
value
} else {
panic!("#[derive(RustEmbed)] attribute name must be folder");
}
}
_ => {
panic!("#[derive(RustEmbed)] attribute name must be folder");
}
};
let folder_path = match literal_value {
&Lit::Str(ref val, _) => val.clone(),
_ => {
panic!("#[derive(RustEmbed)] attribute value must be a string literal");
}
};
if !Path::new(&folder_path).exists() {
panic!(
"#[derive(RustEmbed)] folder '{}' does not exist. cwd: '{}'",
folder_path,
std::env::current_dir().unwrap().to_str().unwrap()
);
};
generate_assets(ident, folder_path)
}
#[proc_macro_derive(RustEmbed, attributes(folder))]
pub fn derive_input_object(input: TokenStream) -> TokenStream {
let s = input.to_string();
let ast = syn::parse_derive_input(&s).unwrap();
let gen = impl_rust_embed(&ast);
gen.parse().unwrap()
}