chore: update documentation

plugins/http/src/error.rs

@@ -5,42 +5,68 @@
 use serde::{Serialize, Serializer};
 use url::Url;
 
+/// Errors that can happen while using the HTTP plugin.
+///
+/// The error is serialized to the frontend as its [`Display`](std::fmt::Display) string.
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
+    /// JSON serialization or deserialization error.
     #[error(transparent)]
     Json(#[from] serde_json::Error),
+    /// File system error, raised for instance when the cookie store file cannot be created or
+    /// opened on startup.
     #[error(transparent)]
     Io(#[from] std::io::Error),
+    /// Error from the underlying [`reqwest`] client, raised while building the client, sending the
+    /// request or reading the response body.
     #[error(transparent)]
     Network(#[from] reqwest::Error),
+    /// Error from the [`http`] crate, raised while building the response of a `data:` URL.
     #[error(transparent)]
     Http(#[from] http::Error),
+    /// A header name given by the frontend is not a valid HTTP header name.
     #[error(transparent)]
     HttpInvalidHeaderName(#[from] http::header::InvalidHeaderName),
+    /// A header value is not a valid HTTP header value.
     #[error(transparent)]
     HttpInvalidHeaderValue(#[from] http::header::InvalidHeaderValue),
     /// URL not allowed by the scope.
+    ///
+    /// Raised for the URL requested by the frontend, and - when the
+    /// [`scope_redirects`](crate::Config::scope_redirects) configuration is enabled - for any
+    /// redirect target that is not allowed by the scope.
     #[error("url not allowed on the configured scope: {0}")]
     UrlNotAllowed(Url),
+    /// Failed to parse a URL.
     #[error(transparent)]
     UrlParseError(#[from] url::ParseError),
     /// HTTP method error.
     #[error(transparent)]
     HttpMethod(#[from] http::method::InvalidMethod),
+    /// The requested URL uses an unsupported scheme. Only `http`, `https` and `data` are handled.
     #[error("scheme {0} not supported")]
     SchemeNotSupport(String),
+    /// The request was aborted by the frontend before the response was received.
     #[error("Request canceled")]
     RequestCanceled,
+    /// Error from the file system plugin.
     #[error(transparent)]
     FsError(#[from] tauri_plugin_fs::Error),
+    /// The `data:` URL could not be processed.
     #[error("failed to process data url")]
     DataUrlError,
+    /// The body of the `data:` URL could not be decoded into bytes.
     #[error("failed to decode data url into bytes")]
     DataUrlDecodeError,
+    /// Error from the Tauri APIs, raised for instance while resolving a path or while reading the
+    /// webview resource table.
     #[error(transparent)]
     Tauri(#[from] tauri::Error),
+    /// A response header value is not valid UTF-8, so it cannot be forwarded to the frontend.
     #[error(transparent)]
     Utf8(#[from] std::string::FromUtf8Error),
+    /// The frontend requested dangerous client settings, but the `dangerous-settings` Cargo
+    /// feature is not enabled.
     #[error("dangerous settings used but are not enabled")]
     DangerousSettings,
 }
@@ -54,4 +80,5 @@ impl Serialize for Error {
     }
 }
 
+/// Alias for a [`Result`](std::result::Result) with the error type [`Error`].
 pub type Result<T> = std::result::Result<T, Error>;