mongo failed with tokio no reactor running since 3.2.0

[Xuanwo]

Versions/Environment

1. What version of Rust are you using?

Latest stable rust.

2. What operating system are you using?

Linux (github action ubuntu 24.04)

3. What versions of the driver and its dependencies are you using? (Run
   cargo pkgid mongodb & cargo pkgid bson)

3.2.0

4. What version of MongoDB are you using? (Check with the MongoDB shell using db.version())

No related. (unable to connect since client side panic)

5. What is your MongoDB topology (standalone, replica set, sharded cluster, serverless)?

No related. (unable to connect since client side panic)

Describe the bug

It used to work correctly 3.1.1, but failed since 3.2.0

thread '<unnamed>' panicked at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/mongodb-3.2.0/src/client.rs:685:13:
there is no reactor running, must be called from the context of a Tokio 1.x runtime
stack backtrace:
   0: rust_begin_unwind
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/std/src/panicking.rs:665:5
   1: core::panicking::panic_fmt
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/panicking.rs:76:14
   2: core::panicking::panic_display
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/panicking.rs:269:5
   3: tokio::runtime::scheduler::Handle::current::panic_cold_display
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/panic.rs:100:13
   4: tokio::runtime::scheduler::Handle::current
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.43.0/src/runtime/scheduler/mod.rs:108:27
   5: tokio::runtime::handle::Handle::current
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.43.0/src/runtime/handle.rs:141:20
   6: mongodb::runtime::join_handle::AsyncJoinHandle<T>::spawn
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/mongodb-3.2.0/src/runtime/join_handle.rs:19:22
   7: mongodb::runtime::spawn
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/mongodb-3.2.0/src/runtime.rs:65:5
   8: <mongodb::client::Client as core::ops::drop::Drop>::drop
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/mongodb-3.2.0/src/client.rs:685:13
   9: core::ptr::drop_in_place<mongodb::client::Client>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  10: core::ptr::drop_in_place<mongodb::db::DatabaseInner>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  11: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  12: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  13: core::ptr::drop_in_place<alloc::sync::Arc<mongodb::db::DatabaseInner>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  14: core::ptr::drop_in_place<mongodb::db::Database>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  15: core::ptr::drop_in_place<mongodb::coll::CollectionInner>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  16: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  17: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  18: core::ptr::drop_in_place<alloc::sync::Arc<mongodb::coll::CollectionInner>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  19: core::ptr::drop_in_place<mongodb::coll::Collection<bson::document::Document>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  20: <tokio::sync::once_cell::OnceCell<T> as core::ops::drop::Drop>::drop::{{closure}}
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.43.0/src/sync/once_cell.rs:109:37
  21: tokio::loom::std::unsafe_cell::UnsafeCell<T>::with_mut
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.43.0/src/loom/std/unsafe_cell.rs:16:9
  22: <tokio::sync::once_cell::OnceCell<T> as core::ops::drop::Drop>::drop
             at /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/tokio-1.43.0/src/sync/once_cell.rs:108:17
  23: core::ptr::drop_in_place<tokio::sync::once_cell::OnceCell<mongodb::coll::Collection<bson::document::Document>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  24: core::ptr::drop_in_place<opendal::services::mongodb::backend::Adapter>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  25: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  26: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  27: core::ptr::drop_in_place<alloc::sync::Arc<opendal::services::mongodb::backend::Adapter>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  28: core::ptr::drop_in_place<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  29: core::ptr::drop_in_place<opendal::layers::error_context::ErrorContextAccessor<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  30: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  31: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  32: core::ptr::drop_in_place<alloc::sync::Arc<opendal::layers::error_context::ErrorContextAccessor<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  33: core::ptr::drop_in_place<opendal::layers::complete::CompleteAccessor<opendal::layers::error_context::ErrorContextAccessor<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  34: core::ptr::drop_in_place<opendal::layers::correctness_check::CorrectnessAccessor<opendal::layers::complete::CompleteAccessor<opendal::layers::error_context::ErrorContextAccessor<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  35: core::ptr::drop_in_place<opendal::layers::type_eraser::TypeEraseAccessor<opendal::layers::correctness_check::CorrectnessAccessor<opendal::layers::complete::CompleteAccessor<opendal::layers::error_context::ErrorContextAccessor<opendal::raw::adapters::kv::backend::Backend<opendal::services::mongodb::backend::Adapter>>>>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  36: core::ptr::drop_in_place<dyn opendal::raw::accessor::AccessDyn>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  37: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  38: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  39: core::ptr::drop_in_place<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  40: core::ptr::drop_in_place<opendal::layers::blocking::BlockingAccessor<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  41: core::ptr::drop_in_place<opendal::layers::type_eraser::TypeEraseAccessor<opendal::layers::blocking::BlockingAccessor<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  42: core::ptr::drop_in_place<dyn opendal::raw::accessor::AccessDyn>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  43: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  44: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  45: core::ptr::drop_in_place<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  46: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  47: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  48: core::ptr::drop_in_place<alloc::sync::Arc<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  49: core::ptr::drop_in_place<opendal::layers::retry::RetryAccessor<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>,opendal::layers::retry::DefaultRetryInterceptor>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  50: core::ptr::drop_in_place<opendal::layers::type_eraser::TypeEraseAccessor<opendal::layers::retry::RetryAccessor<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>,opendal::layers::retry::DefaultRetryInterceptor>>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  51: core::ptr::drop_in_place<dyn opendal::raw::accessor::AccessDyn>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  52: alloc::sync::Arc<T,A>::drop_slow
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:1888:18
  53: <alloc::sync::Arc<T,A> as core::ops::drop::Drop>::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/alloc/src/sync.rs:2575:13
  54: core::ptr::drop_in_place<alloc::sync::Arc<dyn opendal::raw::accessor::AccessDyn>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  55: core::ptr::drop_in_place<opendal::types::operator::blocking_operator::BlockingOperator>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  56: core::ptr::drop_in_place<alloc::boxed::Box<opendal::types::operator::blocking_operator::BlockingOperator>>
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/ptr/mod.rs:521:1
  57: core::mem::drop
             at /rustc/9fc6b43126469e3858e2fe86cafb4f0fd5068869/library/core/src/mem/mod.rs:942:24
  58: Java_org_apache_opendal_Operator_disposeInternal
             at ./src/operator.rs:44:5
  59: <unknown>
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
fatal runtime error: failed to initiate panic, error 5
Aborted (core dumped)

To Reproduce

• Create a gloabl tokio runtime.
• Start mongo driver inside it.

[Xuanwo]

Currently, we can workaround this by exclude 3.2.0:

# mongodb has known issues on 3.2.0: https://github.com/mongodb/mongo-rust-driver/issues/1287
mongodb = { version = ">=3,<3.2.0", optional = true }
mongodb-internal-macros = { version = ">=3,<3.2.0", optional = true }

[abr-egn]

Thanks for the report!

I can't reproduce this failure with a simple client binary (below) - can you give me more information about how you're constructing and managing the client, and ideally minimal code for a reproduction?

From the error stack, it looks like the issue is happening not when the client is being constructed but when it's being dropped; the client does need to do async work to release server-side resources when it's dropped so the associated tokio runtime needs to outlive the client. (This didn't change between 3.1.x and 3.2.0, so I'm not sure why you'd be getting an error when upgrading.)

Test program:

#[tokio::main]
async fn main() {
    let client = mongodb::Client::with_uri_str("mongodb://localhost:27017")
        .await
        .unwrap();
    let names = client.list_database_names().await.unwrap();
    println!("{:?}", names);
}

Cargo.toml:

[package]
name = "minimal-client"
version = "0.1.0"
edition = "2021"

[dependencies]
mongodb = "3.2.0"
tokio = "1.43.0"

Output:

["admin", "config", "local"]

[github-actions]

There has not been any recent activity on this ticket, so we are marking it as stale. If we do not hear anything further from you, this issue will be automatically closed in one week.

[Xuanwo]

Hi, thanks for the response. I'm in holiday currently. I will provide more details and maybe a reproduction later.