fix(updater): release the previous download when downloading again (#3691)

Each `Update.download()` overwrote `this.downloadedBytes` without closing the
previous resource, so the whole previous update payload stayed in the webview
resources table. The previous resource is now closed once the new download
succeeded (so a failed retry still leaves the earlier download installable).

Not covered by e2e: the fixture manifest has no valid signature, so a
download can never succeed there.

plugins/updater/guest-js/index.ts

.changes/updater-js-redownload-leak.md

@@ -0,0 +1,6 @@
+---
+updater: patch
+updater-js: patch
+---
+
+Calling `Update.download()` again now releases the bytes of the previous download instead of keeping them in memory until the webview is destroyed.

plugins/updater/api-iife.js

@@ -1 +1 @@
-if("__TAURI__"in window){var __TAURI_PLUGIN_UPDATER__=function(e,n){"use strict";class t extends n.Resource{constructor(e){super(e.rid),this.available=!0,this.currentVersion=e.currentVersion,this.version=e.version,this.date=e.date,this.body=e.body,this.rawJson=e.rawJson}async download(e,t){a(t);const s=new n.Channel;e&&(s.onmessage=e);const d=await n.invoke("plugin:updater|download",{onEvent:s,rid:this.rid,...t});this.downloadedBytes=new n.Resource(d)}async install(e){if(!this.downloadedBytes)throw new Error("Update.install called before Update.download");await n.invoke("plugin:updater|install",{updateRid:this.rid,bytesRid:this.downloadedBytes.rid,...e}),this.downloadedBytes=void 0}async downloadAndInstall(e,t){a(t);const s=new n.Channel;e&&(s.onmessage=e),await n.invoke("plugin:updater|download_and_install",{onEvent:s,rid:this.rid,...t})}async close(){await(this.downloadedBytes?.close()),await super.close()}}function a(e){e?.headers&&(e.headers=Array.from(new Headers(e.headers).entries()))}return e.Update=t,e.check=async function(e){a(e);const s=await n.invoke("plugin:updater|check",{...e});return s?new t(s):null},e}({},window.__TAURI__.core);Object.defineProperty(window.__TAURI__,"updater",{value:__TAURI_PLUGIN_UPDATER__})}
+if("__TAURI__"in window){var __TAURI_PLUGIN_UPDATER__=function(e,n){"use strict";class t extends n.Resource{constructor(e){super(e.rid),this.available=!0,this.currentVersion=e.currentVersion,this.version=e.version,this.date=e.date,this.body=e.body,this.rawJson=e.rawJson}async download(e,t){a(t);const s=new n.Channel;e&&(s.onmessage=e);const d=await n.invoke("plugin:updater|download",{onEvent:s,rid:this.rid,...t});await(this.downloadedBytes?.close().catch(()=>{})),this.downloadedBytes=new n.Resource(d)}async install(e){if(!this.downloadedBytes)throw new Error("Update.install called before Update.download");await n.invoke("plugin:updater|install",{updateRid:this.rid,bytesRid:this.downloadedBytes.rid,...e}),this.downloadedBytes=void 0}async downloadAndInstall(e,t){a(t);const s=new n.Channel;e&&(s.onmessage=e),await n.invoke("plugin:updater|download_and_install",{onEvent:s,rid:this.rid,...t})}async close(){await(this.downloadedBytes?.close()),await super.close()}}function a(e){e?.headers&&(e.headers=Array.from(new Headers(e.headers).entries()))}return e.Update=t,e.check=async function(e){a(e);const s=await n.invoke("plugin:updater|check",{...e});return s?new t(s):null},e}({},window.__TAURI__.core);Object.defineProperty(window.__TAURI__,"updater",{value:__TAURI_PLUGIN_UPDATER__})}

plugins/updater/guest-js/index.ts

@@ -165,6 +165,9 @@ class Update extends Resource {
       rid: this.rid,
       ...options
     })
+    // release the bytes of a previous download, which would otherwise be kept
+    // in memory until the webview is destroyed
+    await this.downloadedBytes?.close().catch(() => {})
     this.downloadedBytes = new Resource(downloadedBytesRid)
   }