yew_stdweb/services/
storage.rs

1//! This module contains Yew's implementation of a service to
2//! use local and session storage of a browser.
3
4use crate::format::Text;
5use cfg_if::cfg_if;
6use cfg_match::cfg_match;
7use std::fmt;
8use thiserror::Error;
9cfg_if! {
10    if #[cfg(feature = "std_web")] {
11        #[allow(unused_imports)]
12        use stdweb::{_js_impl, js};
13        use stdweb::unstable::TryFrom;
14        use stdweb::web::{Storage};
15    } else if #[cfg(feature = "web_sys")] {
16        use crate::utils;
17        use web_sys::Storage;
18    }
19}
20
21/// Represents errors of a storage.
22#[derive(Debug, Error)]
23enum StorageError {
24    #[error("restore error")]
25    CantRestore,
26}
27
28/// An area to keep the data in.
29#[derive(Debug)]
30pub enum Area {
31    /// Use `localStorage` of a browser.
32    Local,
33    /// Use `sessionStorage` of a browser.
34    Session,
35}
36
37/// A storage service attached to a context.
38pub struct StorageService {
39    storage: Storage,
40}
41
42impl fmt::Debug for StorageService {
43    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
44        f.write_str("StorageService")
45    }
46}
47
48impl StorageService {
49    /// Creates a new storage service instance with specified storage area.
50    pub fn new(area: Area) -> Result<Self, &'static str> {
51        let storage = cfg_match! {
52            feature = "std_web" => ({
53                let storage_name = match area {
54                    Area::Local => "localStorage",
55                    Area::Session => "sessionStorage",
56                };
57                let storage = js! {
58                    try {
59                        return window[@{storage_name}];
60                    } catch(error) {
61                        return error;
62                    }
63                };
64                Storage::try_from(js!( return @{storage.as_ref()}; ))
65            }),
66            feature = "web_sys" => ({
67                let storage = {
68                    match area {
69                        Area::Local => utils::window().local_storage(),
70                        Area::Session => utils::window().session_storage(),
71                    }
72                };
73                storage.map(Option::unwrap)
74            }),
75        };
76
77        storage
78            .map(|storage| StorageService { storage })
79            .map_err(|_| "couldn't aquire storage")
80    }
81
82    /// Stores value to the storage.
83    pub fn store<T>(&mut self, key: &str, value: T)
84    where
85        T: Into<Text>,
86    {
87        if let Ok(data) = value.into() {
88            let result = cfg_match! {
89                feature = "std_web" => self.storage.insert(key, &data),
90                feature = "web_sys" => self.storage.set_item(key, &data),
91            };
92            result.expect("can't insert value to a storage");
93        }
94    }
95
96    /// Restores value from the storage.
97    pub fn restore<T>(&self, key: &str) -> T
98    where
99        T: From<Text>,
100    {
101        let data = cfg_match! {
102            feature = "std_web" => self.storage.get(key),
103            feature = "web_sys" => self.storage.get_item(key).unwrap(),
104        };
105        let data = data.ok_or_else(|| StorageError::CantRestore.into());
106        T::from(data)
107    }
108
109    /// Removes value from the storage.
110    pub fn remove(&mut self, key: &str) {
111        cfg_match! {
112            feature = "std_web" => self.storage.remove(key),
113            feature = "web_sys" => self.storage.remove_item(key).unwrap(),
114        };
115    }
116}
yew_stdweb/services/storage.rs

yew_stdweb/services/
storage.rs
