Tauri Runtime Verso

A tauri runtime to replace the backend with Verso

What is Verso

Verso is a browser built on top of the Servo browser engine, and in our case, we use it as a webview. The reason for this is because the Servo embedding APIs are quite low level and requires the user (embedder) to send everything about the system to drive it, and with Verso, we provide Servo with these things under the hood, then expose some higher level APIs so that you can just let it run and only control it when you need something, this is similar to the windowed vs visual hosting mode of WebView2 except for when using Servo directly, you'll need to pass in more than just user inputs

Usage

To get started, you need to add this crate to your project, and use default-feature = false on tauri to disable the wry feature

  [build-dependencies]
  tauri-build = "2"
+ tauri-runtime-verso-build = { git = "https://github.com/versotile-org/tauri-runtime-verso.git" }

  [dependencies]
- tauri = { version = "2", features = [] }
+ tauri = { version = "2", default-features = false, features = ["common-controls-v6"] }
+ tauri-runtime-verso = { git = "https://github.com/versotile-org/tauri-runtime-verso.git" }

In your build script, add the tauri-runtime-verso-build script, which will download the pre-built versoview to versoview/versoview-{target-triple}

Note we currently only have pre-built versoview for x64 Linux, Windows, MacOS and arm64 MacOS, also the download might take a bit of time if you have a slow internet connection

fn main() {
+   tauri_runtime_verso_build::get_verso_as_external_bin().unwrap();
    tauri_build::build();
}

Then add the downloaded executable to your tauri config file (tauri.conf.json) as an external binary file

  {
+   "bundle": {
+     "externalBin": [
+       "versoview/versoview"
+     ]
+   }
  }

Finally, setup the code like this:

fn main() {
-   tauri::Builder::new()
+   tauri_runtime_verso::builder()
        .run(tauri::generate_context!())
        .unwrap();
}

For more, take a look at the hello world example, or a more sophisticated api example show casing how you can use React, tauri plugins, and tray icons with it

Also, you can checkout the documentation

Common Problems

No such file or directory on Linux

This error means either the path you set through set_verso_path is wrong (this should not be a problem if you're using the externalBin setup from the Usage) or the versoview exectuable requires a more recent version of glibc that your system doesn't have, in this case, you'll need to either update your linux distro or build versoview yourself

Failed to select a version for ...

error: failed to select a version for `tauri-utils`.
    ... required by package `tauri-runtime-verso v0.1.0 (https://github.com/versotile-org/tauri-runtime-verso.git#ad4815ef)`
    ... which satisfies git dependency `tauri-runtime-verso` of package `testo v0.1.0 (/src/testo/src-tauri)`
versions that meet the requirements `=2.6.0` are: 2.6.0

#19

To solve this, relax the version selection in your Cargo.toml file (e.g. tauri = "2" instead of tauri = "2.8.5") and then run cargo update

Since we rely on some unstable/non-semver compatible features of Tauri, we pinned a few tauri crates' versions, this sometimes causes package selection conflicts, and usually a cargo update would fix that

If you rely on a feature in the latest Tauri which the Verso runtime doesn't support yet, file an issue, or a pull request would be much appreciated

Tips

Devtools

Since Verso doesn't have a devtools built-in, you'll need to use the one from the Firefox, first put in this in your code

// This will make the webviews created afters this open up a devtools server on this port,
// setting it to 0 for a random port
tauri_runtime_verso::set_verso_devtools_port(1234);

Then go to about:debugging in Firefox and connect to localhost:1234 there

Known limitations

Security

We currently hard coded the Origin header for the custom protocol IPC to work, but this means Tauri won't be able to check for if the URL is a remote URL or a local one for the capabilities, so right now, please don't use this to load arbitrary websites if you have related settings

Menus

Currently, only the app wide menus on macOS are supported, per window menus are not supported yet

Mobile

We currently only support Linux, Windows, MacOS, so no mobile (e.g. Android / iOS) support yet

If your app targets both desktop and mobile and want to use this runtime only on desktop, you'll need to:

• Include the crates in this repo only in desktop target dependencies
• Enable wry feature on tauri when targeting mobile
• Use tauri::Builder::new() instead of tauri_runtime_verso::builder() on mobile
• Add checks to only run get_verso_as_external_bin when targeting desktop
• Add externalBin only for desktop platforms, either through tauri conf file for each platform or --config flag to target a different configuration file that contains the externalBin field

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For more, checkout the documentation