fix crash when setting datastore and add methods to fetch all datasto…

…res and to remove a datastore (#1512)

* fix: crash when using `WebViewBuilderExtDarwin.with_data_store_identifier`

* feat: macOS: add `wry::fetch_all_data_store_identifiers` and `wry::remove_data_store`

* move api to WebView, make it blocking

* try using a dedicated NSError kind

* fix ios build

* revert back to async, fix crash on error

* update docs

---------

Co-authored-by: Lucas Nogueira <lucas@tauri.app>

.changes/WebViewExtDarwin.md

@@ -0,0 +1,5 @@
+---
+"wry": patch
+---
+
+Added `WebViewExtDarwin` to expose WebView functions available to both macOS and iOS.

.changes/datastore_id_crash_fix.md

@@ -0,0 +1,5 @@
+---
+"wry": patch
+---
+
+fix: crash when using `WebViewBuilderExtDarwin.with_data_store_identifier`

.changes/fetch_all_and_remove_data_store.md

@@ -0,0 +1,5 @@
+---
+"wry": patch
+---
+
+feat: macOS: add `WebViewExtDarwin::fetch_data_store_identifiers` and `WebViewExtDarwin::remove_data_store`.

Cargo.toml

@@ -95,7 +95,13 @@ features = [
 [target.'cfg(target_vendor = "apple")'.dependencies]
 url = "2.5"
 block2 = "0.6"
-objc2 = { version = "0.6", features = ["exception"] }
+objc2 = { version = "0.6", features = [
+    "exception",
+    # because `NSUUID::from_bytes` needs it,
+    # and `WebViewBuilderExtDarwin.with_data_store_identifier` crashes otherwise,
+    # see https://github.com/tauri-apps/tauri/issues/12843
+    "disable-encoding-assertions",
+] }
 objc2-web-kit = { version = "0.3.0", default-features = false, features = [
   "std",
   "objc2-core-foundation",

src/error.rs

@@ -71,4 +71,7 @@ pub enum Error {
   #[error(transparent)]
   #[cfg(any(target_os = "macos", target_os = "ios"))]
   UrlPrase(#[from] url::ParseError),
+  #[cfg(any(target_os = "macos", target_os = "ios"))]
+  #[error("data store is currently opened")]
+  DataStoreInUse,
 }

src/lib.rs

@@ -1391,14 +1391,14 @@ impl<'a> WebViewBuilder<'a> {
   }
 }
 
-#[cfg(any(target_os = "macos", target_os = "ios",))]
+#[cfg(any(target_os = "macos", target_os = "ios"))]
 #[derive(Clone, Default)]
 pub(crate) struct PlatformSpecificWebViewAttributes {
   data_store_identifier: Option<[u8; 16]>,
   traffic_light_inset: Option<dpi::Position>,
 }
 
-#[cfg(any(target_os = "macos", target_os = "ios",))]
+#[cfg(any(target_os = "macos", target_os = "ios"))]
 pub trait WebViewBuilderExtDarwin {
   /// Initialize the WebView with a custom data store identifier.
   /// Can be used as a replacement for data_directory not being available in WKWebView.
@@ -1415,7 +1415,7 @@ pub trait WebViewBuilderExtDarwin {
   fn with_traffic_light_inset<P: Into<dpi::Position>>(self, position: P) -> Self;
 }
 
-#[cfg(any(target_os = "macos", target_os = "ios",))]
+#[cfg(any(target_os = "macos", target_os = "ios"))]
 impl WebViewBuilderExtDarwin for WebViewBuilder<'_> {
   fn with_data_store_identifier(self, identifier: [u8; 16]) -> Self {
     self.and_then(|mut b| {
@@ -2080,6 +2080,38 @@ impl WebViewExtUnix for WebView {
   }
 }
 
+/// Additional methods on `WebView` that are specific to macOS or iOS.
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+pub trait WebViewExtDarwin {
+  /// Prints with extra options
+  fn print_with_options(&self, options: &PrintOptions) -> Result<()>;
+  /// Fetches all Data Store Identifiers of this application
+  ///
+  /// Needs to run on main thread and needs an event loop to run.
+  fn fetch_data_store_identifiers<F: FnOnce(Vec<[u8; 16]>) + Send + 'static>(cb: F) -> Result<()>;
+  /// Deletes a Data Store by an identifier.
+  ///
+  /// You must drop any WebView instances using the data store before you call this method.
+  ///
+  /// Needs to run on main thread and needs an event loop to run.
+  fn remove_data_store<F: FnOnce(Result<()>) + Send + 'static>(uuid: &[u8; 16], cb: F);
+}
+
+#[cfg(any(target_os = "macos", target_os = "ios"))]
+impl WebViewExtDarwin for WebView {
+  fn print_with_options(&self, options: &PrintOptions) -> Result<()> {
+    self.webview.print_with_options(options)
+  }
+
+  fn fetch_data_store_identifiers<F: FnOnce(Vec<[u8; 16]>) + Send + 'static>(cb: F) -> Result<()> {
+    wkwebview::InnerWebView::fetch_data_store_identifiers(cb)
+  }
+
+  fn remove_data_store<F: FnOnce(Result<()>) + Send + 'static>(uuid: &[u8; 16], cb: F) {
+    wkwebview::InnerWebView::remove_data_store(uuid, cb)
+  }
+}
+
 /// Additional methods on `WebView` that are specific to macOS.
 #[cfg(target_os = "macos")]
 pub trait WebViewExtMacOS {
@@ -2091,7 +2123,7 @@ pub trait WebViewExtMacOS {
   fn ns_window(&self) -> Retained<NSWindow>;
   /// Attaches this webview to the given NSWindow and removes it from the current one.
   fn reparent(&self, window: *mut NSWindow) -> Result<()>;
-  // Prints with extra options
+  /// Prints with extra options
   fn print_with_options(&self, options: &PrintOptions) -> Result<()>;
   /// Move the window controls to the specified position.
   /// Normally this is handled by the Window but because `WebViewBuilder::build()` overwrites the window's NSView the controls will flicker on resizing.

src/wkwebview/class/wry_web_view.rs

@@ -2,7 +2,7 @@
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-License-Identifier: MIT
 
-use std::{cell::RefCell, collections::HashMap, sync::Mutex};
+use std::{collections::HashMap, sync::Mutex};
 
 #[cfg(target_os = "macos")]
 use objc2::runtime::ProtocolObject;

src/wkwebview/mod.rs

@@ -71,6 +71,7 @@ use once_cell::sync::Lazy;
 use raw_window_handle::{HasWindowHandle, RawWindowHandle};
 
 use std::{
+  cell::RefCell,
   collections::HashSet,
   ffi::{c_void, CStr, CString},
   net::Ipv4Addr,
@@ -995,6 +996,63 @@ r#"Object.defineProperty(window, 'ipc', {
 
     Ok(())
   }
+
+  /// Fetches all Data Store Identifiers of this application
+  ///
+  /// Needs to run on main thread and needs an event loop to run.
+  pub fn fetch_data_store_identifiers<F: FnOnce(Vec<[u8; 16]>) + Send + 'static>(
+    cb: F,
+  ) -> crate::Result<()> {
+    // make the RcBlock callback be a FnOnce
+    let cb = RefCell::new(Some(cb));
+    let block = block2::RcBlock::new(move |stores: NonNull<NSArray<NSUUID>>| {
+      let uuid_list = unsafe { stores.as_ref() }
+        .to_vec()
+        .iter()
+        .map(|uuid| uuid.as_bytes())
+        .collect();
+      if let Some(cb) = cb.take() {
+        cb(uuid_list);
+      }
+    });
+
+    match MainThreadMarker::new() {
+      Some(mtn) => unsafe {
+        WKWebsiteDataStore::fetchAllDataStoreIdentifiers(&block, mtn);
+        Ok(())
+      },
+      None => Err(Error::NotMainThread),
+    }
+  }
+
+  /// Deletes a Data Store by an identifier
+  ///
+  /// Needs to run on main thread and needs an event loop to run.
+  pub fn remove_data_store<F: FnOnce(crate::Result<()>) + Send + 'static>(uuid: &[u8; 16], cb: F) {
+    let Some(mtm) = MainThreadMarker::new() else {
+      cb(Err(Error::NotMainThread));
+      return;
+    };
+    let identifier = NSUUID::from_bytes(uuid.to_owned());
+
+    // make the RcBlock callback be a FnOnce
+    let cb = RefCell::new(Some(cb));
+    let block = block2::RcBlock::new(move |error: *mut NSError| {
+      if error.is_null() {
+        if let Some(cb) = cb.take() {
+          cb(Ok(()));
+        }
+      } else {
+        if let Some(cb) = cb.take() {
+          cb(Err(Error::DataStoreInUse));
+        }
+      }
+    });
+
+    unsafe {
+      WKWebsiteDataStore::removeDataStoreForIdentifier_completionHandler(&identifier, &block, mtm);
+    }
+  }
 }
 
 pub fn url_from_webview(webview: &WKWebView) -> Result<String> {