tauri_utils/config_v1/
parse.rs

1// Copyright 2019-2024 Tauri Programme within The Commons Conservancy
2// SPDX-License-Identifier: Apache-2.0
3// SPDX-License-Identifier: MIT
4
5#![allow(clippy::result_large_err)]
6
7use serde::de::DeserializeOwned;
8use serde_json::Value;
9use std::ffi::OsStr;
10use std::path::{Path, PathBuf};
11use thiserror::Error;
12
13/// All extensions that are possibly supported, but perhaps not enabled.
14const EXTENSIONS_SUPPORTED: &[&str] = &["json", "json5", "toml"];
15
16/// All configuration formats that are currently enabled.
17const ENABLED_FORMATS: &[ConfigFormat] = &[
18  ConfigFormat::Json,
19  #[cfg(feature = "config-json5")]
20  ConfigFormat::Json5,
21  #[cfg(feature = "config-toml")]
22  ConfigFormat::Toml,
23];
24
25/// The available configuration formats.
26#[derive(Debug, Copy, Clone)]
27enum ConfigFormat {
28  /// The default JSON (tauri.conf.json) format.
29  Json,
30  /// The JSON5 (tauri.conf.json5) format.
31  Json5,
32  /// The TOML (Tauri.toml file) format.
33  Toml,
34}
35
36impl ConfigFormat {
37  /// Maps the config format to its file name.
38  fn into_file_name(self) -> &'static str {
39    match self {
40      Self::Json => "tauri.conf.json",
41      Self::Json5 => "tauri.conf.json5",
42      Self::Toml => "Tauri.toml",
43    }
44  }
45
46  fn into_platform_file_name(self) -> &'static str {
47    match self {
48      Self::Json => {
49        if cfg!(target_os = "macos") {
50          "tauri.macos.conf.json"
51        } else if cfg!(windows) {
52          "tauri.windows.conf.json"
53        } else {
54          "tauri.linux.conf.json"
55        }
56      }
57      Self::Json5 => {
58        if cfg!(target_os = "macos") {
59          "tauri.macos.conf.json5"
60        } else if cfg!(windows) {
61          "tauri.windows.conf.json5"
62        } else {
63          "tauri.linux.conf.json5"
64        }
65      }
66      Self::Toml => {
67        if cfg!(target_os = "macos") {
68          "Tauri.macos.toml"
69        } else if cfg!(windows) {
70          "Tauri.windows.toml"
71        } else {
72          "Tauri.linux.toml"
73        }
74      }
75    }
76  }
77}
78
79/// Represents all the errors that can happen while reading the config.
80#[derive(Debug, Error)]
81#[non_exhaustive]
82pub enum ConfigError {
83  /// Failed to parse from JSON.
84  #[error("unable to parse JSON Tauri config file at {path} because {error}")]
85  FormatJson {
86    /// The path that failed to parse into JSON.
87    path: PathBuf,
88
89    /// The parsing [`serde_json::Error`].
90    error: serde_json::Error,
91  },
92
93  /// Failed to parse from JSON5.
94  #[cfg(feature = "config-json5")]
95  #[error("unable to parse JSON5 Tauri config file at {path} because {error}")]
96  FormatJson5 {
97    /// The path that failed to parse into JSON5.
98    path: PathBuf,
99
100    /// The parsing [`json5::Error`].
101    error: ::json5::Error,
102  },
103
104  /// Failed to parse from TOML.
105  #[cfg(feature = "config-toml")]
106  #[error("unable to parse toml Tauri config file at {path} because {error}")]
107  FormatToml {
108    /// The path that failed to parse into TOML.
109    path: PathBuf,
110
111    /// The parsing [`toml::Error`].
112    error: ::toml::de::Error,
113  },
114
115  /// Unknown config file name encountered.
116  #[error("unsupported format encountered {0}")]
117  UnsupportedFormat(String),
118
119  /// Known file extension encountered, but corresponding parser is not enabled (cargo features).
120  #[error("supported (but disabled) format encountered {extension} - try enabling `{feature}` ")]
121  DisabledFormat {
122    /// The extension encountered.
123    extension: String,
124
125    /// The cargo feature to enable it.
126    feature: String,
127  },
128
129  /// A generic IO error with context of what caused it.
130  #[error("unable to read Tauri config file at {path} because {error}")]
131  Io {
132    /// The path the IO error occurred on.
133    path: PathBuf,
134
135    /// The [`std::io::Error`].
136    error: std::io::Error,
137  },
138}
139
140/// See [`parse`] for specifics, returns a JSON [`Value`] instead of [`Config`].
141pub fn parse_value(path: impl Into<PathBuf>) -> Result<(Value, PathBuf), ConfigError> {
142  do_parse(path.into())
143}
144
145fn do_parse<D: DeserializeOwned>(path: PathBuf) -> Result<(D, PathBuf), ConfigError> {
146  let file_name = path
147    .file_name()
148    .map(OsStr::to_string_lossy)
149    .unwrap_or_default();
150  let lookup_platform_config = ENABLED_FORMATS
151    .iter()
152    .any(|format| file_name == format.into_platform_file_name());
153
154  let json5 = path.with_file_name(if lookup_platform_config {
155    ConfigFormat::Json5.into_platform_file_name()
156  } else {
157    ConfigFormat::Json5.into_file_name()
158  });
159  let toml = path.with_file_name(if lookup_platform_config {
160    ConfigFormat::Toml.into_platform_file_name()
161  } else {
162    ConfigFormat::Toml.into_file_name()
163  });
164
165  let path_ext = path
166    .extension()
167    .map(OsStr::to_string_lossy)
168    .unwrap_or_default();
169
170  if path.exists() {
171    let raw = read_to_string(&path)?;
172
173    // to allow us to easily use the compile-time #[cfg], we always bind
174    #[allow(clippy::let_and_return)]
175    let json = do_parse_json(&raw, &path);
176
177    // we also want to support **valid** json5 in the .json extension if the feature is enabled.
178    // if the json5 is not valid the serde_json error for regular json will be returned.
179    // this could be a bit confusing, so we may want to encourage users using json5 to use the
180    // .json5 extension instead of .json
181    #[cfg(feature = "config-json5")]
182    let json = {
183      match do_parse_json5(&raw, &path) {
184        json5 @ Ok(_) => json5,
185
186        // assume any errors from json5 in a .json file is because it's not json5
187        Err(_) => json,
188      }
189    };
190
191    json.map(|j| (j, path))
192  } else if json5.exists() {
193    #[cfg(feature = "config-json5")]
194    {
195      let raw = read_to_string(&json5)?;
196      do_parse_json5(&raw, &path).map(|config| (config, json5))
197    }
198
199    #[cfg(not(feature = "config-json5"))]
200    Err(ConfigError::DisabledFormat {
201      extension: ".json5".into(),
202      feature: "config-json5".into(),
203    })
204  } else if toml.exists() {
205    #[cfg(feature = "config-toml")]
206    {
207      let raw = read_to_string(&toml)?;
208      do_parse_toml(&raw, &path).map(|config| (config, toml))
209    }
210
211    #[cfg(not(feature = "config-toml"))]
212    Err(ConfigError::DisabledFormat {
213      extension: ".toml".into(),
214      feature: "config-toml".into(),
215    })
216  } else if !EXTENSIONS_SUPPORTED.contains(&path_ext.as_ref()) {
217    Err(ConfigError::UnsupportedFormat(path_ext.to_string()))
218  } else {
219    Err(ConfigError::Io {
220      path,
221      error: std::io::ErrorKind::NotFound.into(),
222    })
223  }
224}
225
226fn do_parse_json<D: DeserializeOwned>(raw: &str, path: &Path) -> Result<D, ConfigError> {
227  serde_json::from_str(raw).map_err(|error| ConfigError::FormatJson {
228    path: path.into(),
229    error,
230  })
231}
232
233#[cfg(feature = "config-json5")]
234fn do_parse_json5<D: DeserializeOwned>(raw: &str, path: &Path) -> Result<D, ConfigError> {
235  ::json5::from_str(raw).map_err(|error| ConfigError::FormatJson5 {
236    path: path.into(),
237    error,
238  })
239}
240
241#[cfg(feature = "config-toml")]
242fn do_parse_toml<D: DeserializeOwned>(raw: &str, path: &Path) -> Result<D, ConfigError> {
243  ::toml::from_str(raw).map_err(|error| ConfigError::FormatToml {
244    path: path.into(),
245    error,
246  })
247}
248
249/// Helper function to wrap IO errors from [`std::fs::read_to_string`] into a [`ConfigError`].
250fn read_to_string(path: &Path) -> Result<String, ConfigError> {
251  std::fs::read_to_string(path).map_err(|error| ConfigError::Io {
252    path: path.into(),
253    error,
254  })
255}
tauri_utils/config_v1/parse.rs

tauri_utils/config_v1/
parse.rs
