Merge pull request #221 from RosLibRust/node-generics

Node generics

CHANGELOG.md

@@ -29,6 +29,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- A new `Ros` trait has been added that all backends implement. This trait behaves like a typical ROS1 node handle, and is easier to work with in generics than directly using TopicProvider or ServiceProvider. 
+
 ### Fixed
 
 ### Changed

example_package/src/main.rs

@@ -11,7 +11,7 @@ use roslibrust::Publish;
 
 // Writing a simple behavior that uses the generic traits from roslibrust
 // and the generated types from the macro above.
-async fn pub_counter(ros: impl roslibrust::TopicProvider) {
+async fn pub_counter(ros: impl roslibrust::Ros) {
     let publisher = ros
         .advertise::<std_msgs::Int16>("example_counter")
         .await

example_package_macro/src/main.rs

@@ -12,7 +12,7 @@ roslibrust::find_and_generate_ros_messages!(
 
 // Writing a simple behavior that uses the generic traits from roslibrust
 // and the generated types from the macro above.
-async fn pub_counter(ros: impl roslibrust::TopicProvider) {
+async fn pub_counter(ros: impl roslibrust::Ros) {
     let publisher = ros
         .advertise::<std_msgs::Int16>("example_counter")
         .await

roslibrust/examples/generic_client.rs

@@ -9,7 +9,7 @@ roslibrust_codegen_macro::find_and_generate_ros_messages!("assets/ros1_common_in
 #[cfg(all(feature = "rosbridge", feature = "ros1"))]
 #[tokio::main]
 async fn main() {
-    use roslibrust::{Publish, Subscribe, TopicProvider};
+    use roslibrust::{Publish, Ros, Subscribe};
     env_logger::init();
 
     // TopicProvider cannot be an "Object Safe Trait" due to its generic parameters
@@ -21,13 +21,13 @@ async fn main() {
     // single application. The critical part is to make TopicProvider a
     // generic type on you Node.
 
-    struct MyNode<T: TopicProvider> {
+    struct MyNode<T: Ros> {
         ros: T,
         name: String,
     }
 
     // Basic example of a node that publishes and subscribes to itself
-    impl<T: TopicProvider> MyNode<T> {
+    impl<T: Ros> MyNode<T> {
         async fn run(self) {
             let publisher = self
                 .ros

roslibrust/examples/generic_client_services.rs

@@ -8,7 +8,7 @@ roslibrust_codegen_macro::find_and_generate_ros_messages!("assets/ros1_common_in
 #[tokio::main]
 async fn main() {
     // Important to bring these traits into scope so we can use them
-    use roslibrust::{Service, ServiceProvider};
+    use roslibrust::{Ros, Service};
     env_logger::init();
 
     // TopicProvider cannot be an "Object Safe Trait" due to its generic parameters
@@ -20,13 +20,13 @@ async fn main() {
     // single application. The critical part is to make TopicProvider a
     // generic type on you Node.
 
-    struct MyNode<T: ServiceProvider + 'static> {
+    struct MyNode<T: Ros> {
         ros: T,
     }
 
     // Basic example of a node that publishes and subscribes to itself
     // This node will work with any backend
-    impl<T: ServiceProvider> MyNode<T> {
+    impl<T: Ros> MyNode<T> {
         fn handle_service(
             _request: std_srvs::SetBoolRequest,
         ) -> Result<std_srvs::SetBoolResponse, Box<dyn std::error::Error + Send + Sync>> {

roslibrust/examples/generic_message.rs

@@ -38,6 +38,7 @@ impl RosMessageType for GenericHeader {
 }
 
 /// Sets up a subscriber that could get either of two versions of a message
+/// Note this is currently only supported by the rosbridge backend as this behavior relies on serde_json's fallback capabilities
 #[cfg(feature = "rosbridge")]
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {

roslibrust_common/src/lib.rs

@@ -131,5 +131,5 @@ pub mod md5sum;
 
 /// Contains the generic traits represent a pubsub system and service system
 /// These traits will be implemented for specific backends to provides access to "ROS Like" functionality
-pub mod topic_provider;
-pub use topic_provider::*; // Bring topic provider traits into root namespace
+pub mod traits;
+pub use traits::*; // Bring topic provider traits into root namespace

roslibrust_common/src/topic_provider.rs → roslibrust_common/src/traits.rs

@@ -90,6 +90,19 @@ pub trait ServiceProvider {
         F: ServiceFn<T>;
 }
 
+/// Represents all "standard" ROS functionality generically supported by roslibrust
+///
+/// Implementors of this trait behave like typical ROS1 node handles.
+/// Cloning the handle does not create additional underlying connections, but instead simply returns another handle
+/// to interact with the underlying node.
+///
+/// Implementors of this trait are expected to be "self de-registering", when the last node handle for a given
+/// node is dropped, the underlying node is expected to be shut down and clean-up after itself
+pub trait Ros: 'static + Send + Sync + TopicProvider + ServiceProvider + Clone {}
+
+/// The Ros trait is auto implemented for any type that implements the required traits
+impl<T: 'static + Send + Sync + TopicProvider + ServiceProvider + Clone> Ros for T {}
+
 #[cfg(test)]
 mod test {
     // This test specifically fails because TopicProvider is not object safe

roslibrust_mock/src/lib.rs

@@ -46,18 +46,19 @@ type TypeErasedCallback = Arc<
 /// A mock ROS implementation that can be substituted for any roslibrust backend in unit tests.
 ///
 /// Implements [TopicProvider] and [ServiceProvider] to provide basic ros functionality.
+#[derive(Clone)]
 pub struct MockRos {
     // We could probably achieve some fancier type erasure than actually serializing the data
     // but this ends up being pretty simple
-    topics: RwLock<BTreeMap<String, (Channel::Sender<Vec<u8>>, Channel::Receiver<Vec<u8>>)>>,
-    services: RwLock<BTreeMap<String, TypeErasedCallback>>,
+    topics: Arc<RwLock<BTreeMap<String, (Channel::Sender<Vec<u8>>, Channel::Receiver<Vec<u8>>)>>>,
+    services: Arc<RwLock<BTreeMap<String, TypeErasedCallback>>>,
 }
 
 impl MockRos {
     pub fn new() -> Self {
         Self {
-            topics: RwLock::new(BTreeMap::new()),
-            services: RwLock::new(BTreeMap::new()),
+            topics: Arc::new(RwLock::new(BTreeMap::new())),
+            services: Arc::new(RwLock::new(BTreeMap::new())),
         }
     }
 }
@@ -289,4 +290,34 @@ mod tests {
         assert_eq!(response.success, true);
         assert_eq!(response.message, "You set my bool!");
     }
+
+    #[tokio::test(flavor = "multi_thread")]
+    async fn test_mock_node() {
+        // Proves that MockRos impls the Ros trait (via auto impl in roslibrust_common)
+        // and can be used as such
+        struct MyNode<T: Ros> {
+            ros: T,
+        }
+
+        impl<T: Ros> MyNode<T> {
+            async fn run(self) {
+                let publisher = self
+                    .ros
+                    .advertise::<std_msgs::String>("/chatter")
+                    .await
+                    .unwrap();
+
+                publisher
+                    .publish(&std_msgs::String {
+                        data: "Hello, world!".to_string(),
+                    })
+                    .await
+                    .unwrap();
+            }
+        }
+
+        let mock_ros = MockRos::new();
+        let node = MyNode { ros: mock_ros };
+        node.run().await;
+    }
 }

roslibrust_ros1/src/lib.rs

@@ -64,7 +64,7 @@ pub(crate) type TypeErasedCallback = dyn Fn(Vec<u8>) -> Result<Vec<u8>, Box<dyn
     + 'static;
 
 // Implement the generic roslibrust trait
-impl TopicProvider for NodeHandle {
+impl TopicProvider for crate::NodeHandle {
     type Publisher<T: RosMessageType> = crate::Publisher<T>;
     type Subscriber<T: RosMessageType> = crate::Subscriber<T>;
 
@@ -163,6 +163,7 @@ impl<T: RosMessageType> Publish<T> for Publisher<T> {
 
 #[cfg(test)]
 mod test {
+    use roslibrust_common::Ros;
     use roslibrust_common::TopicProvider;
 
     // Prove that we've implemented the topic provider trait fully for NodeHandle
@@ -178,7 +179,25 @@ mod test {
         let new_mock: Result<crate::NodeHandle, _> = Err(anyhow::anyhow!("Expected error"));
 
         let _x = MyClient {
+            // Will panic here which is expect, this test just needs to compile to prove
+            // NodeHandle implements TopicProvider
             _client: new_mock.unwrap(), // panic
         };
     }
+
+    #[test]
+    #[should_panic]
+    fn confirm_node_handle_impls_ros() {
+        struct MyClient<T: Ros> {
+            _client: T,
+        }
+
+        let new_mock: Result<crate::NodeHandle, _> = Err(anyhow::anyhow!("Expected error"));
+
+        let _x = MyClient {
+            // Will panic here which is expect, this test just needs to compile to prove
+            // NodeHandle implements Ros
+            _client: new_mock.unwrap(),
+        };
+    }
 }

roslibrust_rosbridge/src/lib.rs

@@ -263,4 +263,21 @@ mod test {
             _client: new_mock.unwrap(), // panic
         };
     }
+
+    #[test]
+    #[should_panic]
+    fn confirm_client_handle_impls_ros() {
+        struct MyClient<T: Ros> {
+            _client: T,
+        }
+
+        let new_mock: std::result::Result<crate::ClientHandle, _> =
+            Err(anyhow::anyhow!("Expected error"));
+
+        let _x = MyClient {
+            // Should panic here, but proves that ClientHandle implements Ros
+            // when this test compiles
+            _client: new_mock.unwrap(),
+        };
+    }
 }

roslibrust_zenoh/src/lib.rs

@@ -8,6 +8,7 @@ use zenoh::bytes::ZBytes;
 
 /// A wrapper around a normal zenoh session that adds roslibrust specific functionality.
 /// Should be created via [ZenohClient::new], and then used via the [TopicProvider] and [ServiceProvider] traits.
+#[derive(Clone)]
 pub struct ZenohClient {
     session: zenoh::Session,
 }
@@ -386,4 +387,20 @@ mod tests {
             ),
             "7374645f737276732f536574426f6f6c/09fb03525b03e7ea1fd3992bafd87e16/service_server_rs/my_set_bool");
     }
+
+    #[test]
+    #[should_panic]
+    fn confirm_client_handle_impls_ros() {
+        struct MyClient<T: Ros> {
+            _client: T,
+        }
+
+        let new_mock: std::result::Result<ZenohClient, _> = Err(anyhow::anyhow!("Expected error"));
+
+        let _x = MyClient {
+            // Should panic here, but proves that ClientHandle implements Ros
+            // when this test compiles
+            _client: new_mock.unwrap(),
+        };
+    }
 }