feat(cli): hotreload support for frontend static files, closes tauri-apps#2173

Author: amrbashir

.changes/cli-static-files-hot-reload.md

@@ -0,0 +1,5 @@
+---
+"cli": "minor"
+---
+
+Hot-reload the frontend when `tauri.conf.json > build > devPath` points to a directory.

.changes/utils-mimetype.md

@@ -0,0 +1,5 @@
+---
+"tauri-utils": "patch"
+---
+
+Add `mime_type` module

core/tauri-runtime/Cargo.toml

@@ -30,7 +30,6 @@ tauri-utils = { version = "1.1.1", path = "../tauri-utils" }
 uuid = { version = "1", features = [ "v4" ] }
 http = "0.2.4"
 http-range = "0.1.4"
-infer = "0.7"
 raw-window-handle = "0.5"
 rand = "0.8"
 

core/tauri-runtime/src/http/mod.rs

@@ -8,11 +8,12 @@ mod request;
 mod response;
 
 pub use self::{
-  mime_type::MimeType,
   request::{Request, RequestParts},
   response::{Builder as ResponseBuilder, Response, ResponseParts},
 };
 
+pub use tauri_utils::mime_type::MimeType;
+
 // re-expose default http types
 pub use http::{header, method, status, uri::InvalidUri, version, Uri};
 

core/tauri-utils/Cargo.toml

@@ -35,6 +35,7 @@ glob = { version = "0.3.0", optional = true }
 walkdir = { version = "2", optional = true }
 memchr = "2.4"
 semver = "1"
+infer = "0.7"
 
 [target."cfg(target_os = \"linux\")".dependencies]
 heck = "0.4"

core/tauri-utils/src/lib.rs

@@ -14,6 +14,7 @@ pub mod assets;
 pub mod config;
 pub mod html;
 pub mod io;
+pub mod mime_type;
 pub mod platform;
 /// Prepare application resources and sidecars.
 #[cfg(feature = "resources")]

core/tauri-utils/src/mime_type.rs

@@ -0,0 +1,136 @@
+// Copyright 2019-2022 Tauri Programme within The Commons Conservancy
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-License-Identifier: MIT
+
+#![allow(missing_docs)]
+
+use std::fmt;
+
+const MIMETYPE_PLAIN: &str = "text/plain";
+
+/// [Web Compatible MimeTypes](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types#important_mime_types_for_web_developers)
+pub enum MimeType {
+  Css,
+  Csv,
+  Html,
+  Ico,
+  Js,
+  Json,
+  Jsonld,
+  OctetStream,
+  Rtf,
+  Svg,
+  Mp4,
+}
+
+impl std::fmt::Display for MimeType {
+  fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    let mime = match self {
+      MimeType::Css => "text/css",
+      MimeType::Csv => "text/csv",
+      MimeType::Html => "text/html",
+      MimeType::Ico => "image/vnd.microsoft.icon",
+      MimeType::Js => "text/javascript",
+      MimeType::Json => "application/json",
+      MimeType::Jsonld => "application/ld+json",
+      MimeType::OctetStream => "application/octet-stream",
+      MimeType::Rtf => "application/rtf",
+      MimeType::Svg => "image/svg+xml",
+      MimeType::Mp4 => "video/mp4",
+    };
+    write!(f, "{}", mime)
+  }
+}
+
+impl MimeType {
+  /// parse a URI suffix to convert text/plain mimeType to their actual web compatible mimeType.
+  pub fn parse_from_uri(uri: &str) -> MimeType {
+    let suffix = uri.split('.').last();
+    match suffix {
+      Some("bin") => Self::OctetStream,
+      Some("css") => Self::Css,
+      Some("csv") => Self::Csv,
+      Some("html") => Self::Html,
+      Some("ico") => Self::Ico,
+      Some("js") => Self::Js,
+      Some("json") => Self::Json,
+      Some("jsonld") => Self::Jsonld,
+      Some("mjs") => Self::Js,
+      Some("rtf") => Self::Rtf,
+      Some("svg") => Self::Svg,
+      Some("mp4") => Self::Mp4,
+      // Assume HTML when a TLD is found for eg. `wry:://tauri.app` | `wry://hello.com`
+      Some(_) => Self::Html,
+      // https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types
+      // using octet stream according to this:
+      None => Self::OctetStream,
+    }
+  }
+
+  /// infer mimetype from content (or) URI if needed.
+  pub fn parse(content: &[u8], uri: &str) -> String {
+    let mime = if uri.ends_with(".svg") {
+      // when reading svg, we can't use `infer`
+      None
+    } else {
+      infer::get(content).map(|info| info.mime_type())
+    };
+
+    match mime {
+      Some(mime) if mime == MIMETYPE_PLAIN => Self::parse_from_uri(uri).to_string(),
+      None => Self::parse_from_uri(uri).to_string(),
+      Some(mime) => mime.to_string(),
+    }
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn should_parse_mimetype_from_uri() {
+    let css = MimeType::parse_from_uri(
+      "https://unpkg.com/browse/[email protected]/dist/css/bootstrap-grid.css",
+    )
+    .to_string();
+    assert_eq!(css, "text/css".to_string());
+
+    let csv: String = MimeType::parse_from_uri("https://example.com/random.csv").to_string();
+    assert_eq!(csv, "text/csv".to_string());
+
+    let ico: String =
+      MimeType::parse_from_uri("https://icons.duckduckgo.com/ip3/microsoft.com.ico").to_string();
+    assert_eq!(ico, String::from("image/vnd.microsoft.icon"));
+
+    let html: String = MimeType::parse_from_uri("https://tauri.app/index.html").to_string();
+    assert_eq!(html, String::from("text/html"));
+
+    let js: String =
+      MimeType::parse_from_uri("https://unpkg.com/[email protected]/umd/react.production.min.js")
+        .to_string();
+    assert_eq!(js, "text/javascript".to_string());
+
+    let json: String =
+      MimeType::parse_from_uri("https://unpkg.com/browse/[email protected]/build-info.json").to_string();
+    assert_eq!(json, String::from("application/json"));
+
+    let jsonld: String = MimeType::parse_from_uri("https:/example.com/hello.jsonld").to_string();
+    assert_eq!(jsonld, String::from("application/ld+json"));
+
+    let mjs: String = MimeType::parse_from_uri("https://example.com/bundled.mjs").to_string();
+    assert_eq!(mjs, String::from("text/javascript"));
+
+    let rtf: String = MimeType::parse_from_uri("https://example.com/document.rtf").to_string();
+    assert_eq!(rtf, String::from("application/rtf"));
+
+    let svg: String = MimeType::parse_from_uri("https://example.com/picture.svg").to_string();
+    assert_eq!(svg, String::from("image/svg+xml"));
+
+    let mp4: String = MimeType::parse_from_uri("https://example.com/video.mp4").to_string();
+    assert_eq!(mp4, String::from("video/mp4"));
+
+    let custom_scheme = MimeType::parse_from_uri("wry://tauri.app").to_string();
+    assert_eq!(custom_scheme, String::from("text/html"));
+  }
+}