Using Deno core in an app that already had its own tokio runtime

I am using the deno_core and deno_ast crates to "Roll my own JavaScript runtime", as seen here (https://github.com/denoland/roll-your-own-javascript-runtime/blob/main/src/main.rs#L153-L159 ), but I don't know how to launch my deno runtime properly within my existing tokio runtime.

I've tried using a HandleHandle and spawning a thread and using block_on, like below:

pub(crate) fn run_js(args: &RunArgs) {
    let file_path = args.file.to_owned().into_string().unwrap();
    let handle = tokio::runtime::Handle::current();
    std::thread::spawn(move || {
        // Using Handle::block_on to run async code in the new thread.
        if let Err(error) = handle.block_on(run_js(file_path.as_str())) {
            eprintln!("error: {error}");
        }
    })
    .join()
    .unwrap();
}

pub(crate) fn run_js(args: &RunArgs) {
    let file_path = args.file.to_owned().into_string().unwrap();
    let handle = tokio::runtime::Handle::current();
    std::thread::spawn(move || {
        // Using Handle::block_on to run async code in the new thread.
        if let Err(error) = handle.block_on(run_js(file_path.as_str())) {
            eprintln!("error: {error}");
        }
    })
    .join()
    .unwrap();
}

But the moment I execute the example script, it fails at setTimeoutsetTimeout.

console.log("Waiting 2 seconds for timeout...");
setTimeout(() => {
  console.log("Hello World from timeout!");
}, 2000);

console.log("Waiting 2 seconds for timeout...");
setTimeout(() => {
  console.log("Hello World from timeout!");
}, 2000);

I end up with output like below:

[out]: "Waiting 2 seconds for timeout..."
Error:   × Main thread panicked.
  ├─▶ at /Users/my_user_name/.cargo/registry/src/index.crates.io-6f17d22bba15001f/deno_unsync-0.3.4/src/task.rs:56:3
  ╰─▶ assertion failed: Handle::current().runtime_flavor() == RuntimeFlavor::CurrentThread
  help: set the `RUST_BACKTRACE=1` environment variable to display a backtrace.

fatal runtime error: failed to initiate panic, error 5

[out]: "Waiting 2 seconds for timeout..."
Error:   × Main thread panicked.
  ├─▶ at /Users/my_user_name/.cargo/registry/src/index.crates.io-6f17d22bba15001f/deno_unsync-0.3.4/src/task.rs:56:3
  ╰─▶ assertion failed: Handle::current().runtime_flavor() == RuntimeFlavor::CurrentThread
  help: set the `RUST_BACKTRACE=1` environment variable to display a backtrace.

fatal runtime error: failed to initiate panic, error 5

GitHub

roll-your-own-javascript-runtime/src/main.rs at main · denoland/rol...

Contribute to denoland/roll-your-own-javascript-runtime development by creating an account on GitHub.

Using Deno core in an app that already had its own tokio runtime

pub(crate) fn run_js(args: &RunArgs) {
    let file_path = args.file.to_owned().into_string().unwrap();
    let handle = tokio::runtime::Handle::current();
    std::thread::spawn(move || {
        // Using Handle::block_on to run async code in the new thread.
        if let Err(error) = handle.block_on(run_js(file_path.as_str())) {
            eprintln!("error: {error}");
        }
    })
    .join()
    .unwrap();
}

pub(crate) fn run_js(args: &RunArgs) {
    let file_path = args.file.to_owned().into_string().unwrap();
    let handle = tokio::runtime::Handle::current();
    std::thread::spawn(move || {
        // Using Handle::block_on to run async code in the new thread.
        if let Err(error) = handle.block_on(run_js(file_path.as_str())) {
            eprintln!("error: {error}");
        }
    })
    .join()
    .unwrap();
}

But the moment I execute the example script, it fails at setTimeoutsetTimeout.

console.log("Waiting 2 seconds for timeout...");
setTimeout(() => {
  console.log("Hello World from timeout!");
}, 2000);

console.log("Waiting 2 seconds for timeout...");
setTimeout(() => {
  console.log("Hello World from timeout!");
}, 2000);

I end up with output like below:

[out]: "Waiting 2 seconds for timeout..."
Error:   × Main thread panicked.
  ├─▶ at /Users/my_user_name/.cargo/registry/src/index.crates.io-6f17d22bba15001f/deno_unsync-0.3.4/src/task.rs:56:3
  ╰─▶ assertion failed: Handle::current().runtime_flavor() == RuntimeFlavor::CurrentThread
  help: set the `RUST_BACKTRACE=1` environment variable to display a backtrace.

fatal runtime error: failed to initiate panic, error 5

[out]: "Waiting 2 seconds for timeout..."
Error:   × Main thread panicked.
  ├─▶ at /Users/my_user_name/.cargo/registry/src/index.crates.io-6f17d22bba15001f/deno_unsync-0.3.4/src/task.rs:56:3
  ╰─▶ assertion failed: Handle::current().runtime_flavor() == RuntimeFlavor::CurrentThread
  help: set the `RUST_BACKTRACE=1` environment variable to display a backtrace.

fatal runtime error: failed to initiate panic, error 5

GitHub

roll-your-own-javascript-runtime/src/main.rs at main · denoland/rol...

Contribute to denoland/roll-your-own-javascript-runtime development by creating an account on GitHub.

Using Deno core in an app that already had its own tokio runtime

Using Deno core in an app that already had its own tokio runtime

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