feat: expose auto-updater method to update from file on disk

lib/browser/api/auto-updater/auto-updater-win.ts

@@ -65,6 +65,10 @@ class AutoUpdater extends EventEmitter implements Electron.AutoUpdater {
     }
   }
 
+  prepareUpdateFromFile () {
+    throw new Error('Not supported on Windows');
+  }
+
   // Private: Emit both error object and message, this is to keep compatibility
   // with Old APIs.
   emitError (error: Error) {

patches/squirrel.mac/.patches

@@ -7,3 +7,4 @@ fix_abort_installation_attempt_at_the_final_mile_if_the_app_is.patch
 feat_add_ability_to_prevent_version_downgrades.patch
 refactor_use_non-deprecated_nskeyedarchiver_apis.patch
 chore_turn_off_launchapplicationaturl_deprecation_errors_in_squirrel.patch
+hack_expose_verifyandprepareupdateexternal.patch

patches/squirrel.mac/hack_expose_verifyandprepareupdateexternal.patch

@@ -0,0 +1,97 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Julian Waller <[email protected]>
+Date: Fri, 31 Jan 2025 01:10:05 +0000
+Subject: hack: expose verifyAndPrepareUpdateExternal
+
+
+diff --git a/Squirrel/SQRLUpdater.h b/Squirrel/SQRLUpdater.h
+index 87119399e8548e04134d1ee0cd18f85c2ad672c2..3d0435b80b8f23f129edff9b188f32c8af3b48d5 100644
+--- a/Squirrel/SQRLUpdater.h
++++ b/Squirrel/SQRLUpdater.h
+@@ -9,6 +9,8 @@
+ #import <Foundation/Foundation.h>
+ #import <ReactiveObjC/ReactiveObjC.h>
+
++#import "SQRLUpdate.h"
++
+ // Represents the current state of the updater.
+ //
+ // SQRLUpdaterStateIdle              - Doing absolutely diddly squat.
+@@ -144,7 +146,7 @@ typedef enum {
+ //
+ // Returns the initialized `SQRLUpdater`.
+ - (id)initWithUpdateRequest:(NSURLRequest *)updateRequest
+-					   forVersion:(NSString*)version;
++					forVersion:(NSString*)version;
+
+ // Initializes an updater that will send the given request to check for updates
+ // and passes a block to provide requests for the update downloads.
+@@ -197,6 +199,15 @@ typedef enum {
+ // wrong before termination. The signal will never complete.
+ - (RACSignal *)relaunchToInstallUpdate;
+
++// Validates the code signature of the given update bundle, then prepares it for
++// installation.
++//
++// Upon success, the update will be automatically installed after the
++// application terminates.
++//
++// update - Describes the update to verify and prepare. This must not be nil.
++- (RACSignal *)verifyAndPrepareUpdateExternal:(SQRLUpdate *)update fromBundle:(NSBundle *)updateBundle;
++
+ - (BOOL)isRunningOnReadOnlyVolume;
+ - (RACSignal *)updateFromJSONData:(NSData *)data;
+
+diff --git a/Squirrel/SQRLUpdater.m b/Squirrel/SQRLUpdater.m
+index 592c7ea51515aab96934e0117df3c8065494fa09..9039276910b6a8b26aabfb385827f9430b3a6e9b 100644
+--- a/Squirrel/SQRLUpdater.m
++++ b/Squirrel/SQRLUpdater.m
+@@ -722,6 +722,48 @@ - (RACSignal *)truncateLogs {
+
+ #pragma mark Installing Updates
+
++- (RACSignal *)verifyAndPrepareUpdateExternal:(SQRLUpdate *)update fromBundle:(NSBundle *)updateBundle {
++	NSParameterAssert(update != nil);
++	NSParameterAssert(updateBundle != nil);
++
++	if (_signature == nil) {
++		NSError *error = nil;
++		_signature = [SQRLCodeSignature currentApplicationSignature:&error];
++		if (_signature == nil) {
++	#if DEBUG
++			NSLog(@"Could not get code signature for running application, application updates are disabled: %@", error);
++			return nil;
++	#else
++			NSDictionary *exceptionInfo = @{ NSUnderlyingErrorKey: error };
++			@throw [NSException exceptionWithName:NSInternalInconsistencyException reason:@"Could not get code signature for running application" userInfo:exceptionInfo];
++	#endif
++		}
++	}
++
++	if (!_shipItLauncher) {
++		@weakify(self)
++		_shipItLauncher = [[[RACSignal
++			defer:^{
++				@strongify(self);
++
++				NSURL *targetURL = NSRunningApplication.currentApplication.bundleURL;
++
++				BOOL targetWritable = [self canWriteToURL:targetURL];
++				BOOL parentWritable = [self canWriteToURL:targetURL.URLByDeletingLastPathComponent];
++				BOOL launchPrivileged = !targetWritable || !parentWritable;
++				if ([[NSUserDefaults standardUserDefaults] boolForKey:@"SquirrelMacEnableDirectContentsWrite"]) {
++					// If SquirrelMacEnableDirectContentsWrite is enabled we don't care if the parent directory is writeable or not
++					BOOL launchPrivileged = !targetWritable;
++				}
++				return [SQRLShipItLauncher launchPrivileged:launchPrivileged];
++			}]
++			replayLazily]
++			setNameWithFormat:@"shipItLauncher"];
++	}
++
++	return [self verifyAndPrepareUpdate:update fromBundle:updateBundle];
++}
++
+ - (RACSignal *)verifyAndPrepareUpdate:(SQRLUpdate *)update fromBundle:(NSBundle *)updateBundle {
+ 	NSParameterAssert(update != nil);
+ 	NSParameterAssert(updateBundle != nil);

shell/browser/api/electron_api_auto_updater.cc

@@ -138,6 +138,8 @@ gin::ObjectTemplateBuilder AutoUpdater::GetObjectTemplateBuilder(
       .SetMethod("isVersionAllowedForUpdate",
                  &auto_updater::AutoUpdater::IsVersionAllowedForUpdate)
 #endif
+      .SetMethod("prepareUpdateFromFile",
+                 &auto_updater::AutoUpdater::PrepareUpdateFromFile)
       .SetMethod("quitAndInstall", &AutoUpdater::QuitAndInstall);
 }
 

shell/browser/auto_updater.cc

@@ -30,6 +30,10 @@ void AutoUpdater::CheckForUpdates() {}
 
 void AutoUpdater::QuitAndInstall() {}
 
+bool AutoUpdater::PrepareUpdateFromFile(gin::Arguments* args) {
+  return false;
+}
+
 bool AutoUpdater::IsVersionAllowedForUpdate(const std::string& current_version,
                                             const std::string& target_version) {
   return false;

shell/browser/auto_updater.h

@@ -67,6 +67,7 @@ class AutoUpdater {
   static void SetFeedURL(gin::Arguments* args);
   static void CheckForUpdates();
   static void QuitAndInstall();
+  static bool PrepareUpdateFromFile(gin::Arguments* args);
 
   static bool IsVersionAllowedForUpdate(const std::string& current_version,
                                         const std::string& target_version);

shell/browser/auto_updater_mac.mm

@@ -180,6 +180,68 @@
   }
 }
 
+bool AutoUpdater::PrepareUpdateFromFile(gin::Arguments* args) {
+  gin_helper::ErrorThrower thrower(args->isolate());
+
+  if (update_url_ != "") {
+    thrower.ThrowError(
+        "prepareUpdateFromFile cannot be called after setFeedUrl");
+    return false;
+  }
+
+  if (g_update_available) {
+    thrower.ThrowError("An update is already pending");
+    return false;
+  }
+
+  std::string filename;
+  v8::Local<v8::Value> first_arg = args->PeekNext();
+  if (!first_arg.IsEmpty() && first_arg->IsString()) {
+    args->GetNext(&filename);
+  } else {
+    thrower.ThrowError("missing filename of bundle");
+    return false;
+  }
+
+  Delegate* delegate = GetDelegate();
+  if (!delegate) {
+    thrower.ThrowError("updater not fully initialised!");
+    return false;
+  }
+
+  if (g_updater)
+    g_updater = nil;
+
+  // Initialize the SQRLUpdater.
+  g_updater = [SQRLUpdater alloc];
+
+  // TODO - convert better
+  NSURL* url = [NSURL URLWithString:base::SysUTF8ToNSString(filename)];
+  NSBundle* bundle = [NSBundle bundleWithURL:url];
+
+  if (!bundle) {
+    thrower.ThrowError("app bundle not found!");
+    return false;
+  }
+
+  SQRLUpdate* update =
+      [SQRLUpdate alloc];  // This appears to not really be used, but is a
+                           // necessary parameter
+
+  [[g_updater verifyAndPrepareUpdateExternal:update fromBundle:bundle]
+      subscribeError:^(NSError* error) {
+        if (delegate)
+          delegate->OnError(base::SysNSStringToUTF8(error.localizedDescription),
+                            error.code, base::SysNSStringToUTF8(error.domain));
+      }
+      completed:^() {
+        g_update_available = true;
+        delegate->OnUpdateAvailable();
+      }];
+
+  return true;
+}
+
 bool AutoUpdater::IsVersionAllowedForUpdate(const std::string& current_version,
                                             const std::string& target_version) {
   return [SQRLUpdater