uni_app/
native_fs.rs

1use std;
2use std::io::ErrorKind;
3use std::io::Read;
4use std::str;
5
6/// the root filesystem API
7pub struct FileSystem {}
8/// synchronous (native) / asynchronous (web) file API
9pub enum File {
10    Native(std::fs::File),
11}
12
13pub type IoError = std::io::Error;
14pub type IoErrorKind = std::io::ErrorKind;
15
16impl FileSystem {
17    /// open a file.
18    /// For a file to be accessible from both native and web build, it should be placed
19    /// in a www/ directory in your project's root directory, for example www/config.json.
20    /// You can then open this file with `FileSystem::open("config.json")`.
21    /// When running your native project, use `cd www && cargo run`.
22    /// When deploying on the web, the file should simply be in the same directory as index.html, as config.json.
23    /// Note that on wasm target, this works with any URL, you can do :
24    /// `FileSystem::open('https://raw.githubusercontent.com/unrust/uni-app/master/www/test.txt')`
25    /// To be able to load data from an URL in native mode, you have to enable the http feature.
26    pub fn open(s: &str) -> Result<File, IoError> {
27        if s.starts_with("http") {
28            Err(std::io::Error::new(
29                ErrorKind::Other,
30                format!(
31                    "error : could not read {} : http feature not enabled in uni-app::FileSystem",
32                    s
33                ),
34            ))
35        } else {
36            Ok(File::Native(std::fs::File::open(s)?))
37        }
38    }
39}
40
41impl File {
42    /// Once the file has been loaded (see [`File::is_ready`]), returns the file content as `Vec<u8>`
43    pub fn read_binary(&mut self) -> Result<Vec<u8>, IoError> {
44        let mut buf = Vec::new();
45        match self {
46            File::Native(f) => {
47                f.read_to_end(&mut buf)?;
48            }
49        }
50        Ok(buf)
51    }
52    /// Once the file has been loaded (see [`File::is_ready`]), returns the file content as a String
53    pub fn read_text(&mut self) -> Result<String, IoError> {
54        let mut data = String::new();
55        match self {
56            File::Native(f) => match f.read_to_string(&mut data) {
57                Ok(_) => Ok(data),
58                Err(e) => Err(std::io::Error::new(ErrorKind::Other, e)),
59            },
60        }
61    }
62    /// return true if the file has been loaded
63    /// On native target, files are loaded synchronously.
64    /// As soon as [`FileSystem::open`] returns, the file is ready.
65    /// [`File::read_binary`] and [`File::read_text`] can be called immediately.
66    /// On web target, files are loaded asynchronously.
67    /// You have to poll [`File::is_ready`] until it returns true.
68    /// Only then you can call [`File::read_binary`] or [`File::read_text`].
69    pub fn is_ready(&mut self) -> bool {
70        true
71    }
72}
uni_app/native_fs.rs

uni_app/
native_fs.rs
