feat(types): Add gRPC Richer Error Model support (Examples) (#1300)

* types: remove unnecessary cloning from `ErrorDetails` getters

Breaking change.

* examples: add `richer-error` examples

Following implementation at flemosr/tonic-richer-error.

examples/Cargo.toml

@@ -233,6 +233,26 @@ name = "json-codec-server"
 path = "src/json-codec/server.rs"
 required-features = ["json-codec"]
 
+[[bin]]
+name = "richer-error-client"
+path = "src/richer-error/client.rs"
+required-features = ["types"]
+
+[[bin]]
+name = "richer-error-server"
+path = "src/richer-error/server.rs"
+required-features = ["types"]
+
+[[bin]]
+name = "richer-error-client-vec"
+path = "src/richer-error/client_vec.rs"
+required-features = ["types"]
+
+[[bin]]
+name = "richer-error-server-vec"
+path = "src/richer-error/server_vec.rs"
+required-features = ["types"]
+
 [features]
 gcp = ["dep:prost-types", "tonic/tls"]
 routeguide = ["dep:async-stream", "dep:futures", "tokio-stream", "dep:rand", "dep:serde", "dep:serde_json"]
@@ -254,8 +274,9 @@ tls-rustls = ["dep:hyper", "dep:hyper-rustls", "dep:tower", "tower-http/util", "
 dynamic-load-balance = ["dep:tower"]
 timeout = ["tokio/time", "dep:tower"]
 tls-client-auth = ["tonic/tls"]
+types = ["dep:tonic-types"]
 
-full = ["gcp", "routeguide", "reflection", "autoreload", "health", "grpc-web", "tracing", "hyper-warp", "hyper-warp-multiplex", "uds", "streaming", "mock", "tower", "json-codec", "compression", "tls", "tls-rustls", "dynamic-load-balance", "timeout", "tls-client-auth"]
+full = ["gcp", "routeguide", "reflection", "autoreload", "health", "grpc-web", "tracing", "hyper-warp", "hyper-warp-multiplex", "uds", "streaming", "mock", "tower", "json-codec", "compression", "tls", "tls-rustls", "dynamic-load-balance", "timeout", "tls-client-auth", "types"]
 default = ["full"]
 
 [dependencies]
@@ -267,6 +288,7 @@ tonic = { path = "../tonic" }
 tonic-web = { path = "../tonic-web", optional = true }
 tonic-health = { path = "../tonic-health", optional = true }
 tonic-reflection = { path = "../tonic-reflection", optional = true }
+tonic-types = { path = "../tonic-types", optional = true }
 async-stream = { version = "0.3", optional = true }
 futures = { version = "0.3", default-features = false, optional = true }
 tokio-stream = { version = "0.1", optional = true }

examples/README.md

@@ -153,3 +153,33 @@ The autoload example requires the following crates installed globally:
 
 * [systemfd](https://crates.io/crates/systemfd)
 * [cargo-watch](https://crates.io/crates/cargo-watch)
+
+## Richer Error
+
+Both clients and both servers do the same thing, but using the two different
+approaches. Run one of the servers in one terminal, and then run the clients
+in another.
+
+### Client using the `ErrorDetails` struct
+
+```bash
+$ cargo run --bin richer-error-client
+```
+
+### Client using a vector of error message types
+
+```bash
+$ cargo run --bin richer-error-client-vec
+```
+
+### Server using the `ErrorDetails` struct
+
+```bash
+$ cargo run --bin richer-error-server
+```
+
+### Server using a vector of error message types
+
+```bash
+$ cargo run --bin richer-error-server-vec
+```

examples/src/richer-error/client.rs

@@ -0,0 +1,52 @@
+use tonic_types::StatusExt;
+
+use hello_world::greeter_client::GreeterClient;
+use hello_world::HelloRequest;
+
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut client = GreeterClient::connect("http://[::1]:50051").await?;
+
+    let request = tonic::Request::new(HelloRequest {
+        // Valid request
+        // name: "Tonic".into(),
+        // Name cannot be empty
+        name: "".into(),
+        // Name is too long
+        // name: "some excessively long name".into(),
+    });
+
+    let response = match client.say_hello(request).await {
+        Ok(response) => response,
+        Err(status) => {
+            println!(" Error status received. Extracting error details...\n");
+
+            let err_details = status.get_error_details();
+
+            if let Some(bad_request) = err_details.bad_request() {
+                // Handle bad_request details
+                println!(" {:?}", bad_request);
+            }
+            if let Some(help) = err_details.help() {
+                // Handle help details
+                println!(" {:?}", help);
+            }
+            if let Some(localized_message) = err_details.localized_message() {
+                // Handle localized_message details
+                println!(" {:?}", localized_message);
+            }
+
+            println!();
+
+            return Ok(());
+        }
+    };
+
+    println!(" Successfull response received.\n\n {:?}\n", response);
+
+    Ok(())
+}

examples/src/richer-error/client_vec.rs

@@ -0,0 +1,58 @@
+use tonic_types::{ErrorDetail, StatusExt};
+
+use hello_world::greeter_client::GreeterClient;
+use hello_world::HelloRequest;
+
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut client = GreeterClient::connect("http://[::1]:50051").await?;
+
+    let request = tonic::Request::new(HelloRequest {
+        // Valid request
+        // name: "Tonic".into(),
+        // Name cannot be empty
+        name: "".into(),
+        // Name is too long
+        // name: "some excessively long name".into(),
+    });
+
+    let response = match client.say_hello(request).await {
+        Ok(response) => response,
+        Err(status) => {
+            println!(" Error status received. Extracting error details...\n");
+
+            let err_details = status.get_error_details_vec();
+
+            for (i, err_detail) in err_details.iter().enumerate() {
+                println!("err_detail[{i}]");
+                match err_detail {
+                    ErrorDetail::BadRequest(bad_request) => {
+                        // Handle bad_request details
+                        println!(" {:?}", bad_request);
+                    }
+                    ErrorDetail::Help(help) => {
+                        // Handle help details
+                        println!(" {:?}", help);
+                    }
+                    ErrorDetail::LocalizedMessage(localized_message) => {
+                        // Handle localized_message details
+                        println!(" {:?}", localized_message);
+                    }
+                    _ => {}
+                }
+            }
+
+            println!();
+
+            return Ok(());
+        }
+    };
+
+    println!(" Successfull response received.\n\n {:?}\n", response);
+
+    Ok(())
+}

examples/src/richer-error/server.rs

@@ -0,0 +1,71 @@
+use tonic::{transport::Server, Code, Request, Response, Status};
+use tonic_types::{ErrorDetails, StatusExt};
+
+use hello_world::greeter_server::{Greeter, GreeterServer};
+use hello_world::{HelloReply, HelloRequest};
+
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
+}
+
+#[derive(Default)]
+pub struct MyGreeter {}
+
+#[tonic::async_trait]
+impl Greeter for MyGreeter {
+    async fn say_hello(
+        &self,
+        request: Request<HelloRequest>,
+    ) -> Result<Response<HelloReply>, Status> {
+        println!("Got a request from {:?}", request.remote_addr());
+
+        // Extract request data
+        let name = request.into_inner().name;
+
+        // Create empty ErrorDetails struct
+        let mut err_details = ErrorDetails::new();
+
+        // Add error details conditionally
+        if name.is_empty() {
+            err_details.add_bad_request_violation("name", "name cannot be empty");
+        } else if name.len() > 20 {
+            err_details.add_bad_request_violation("name", "name is too long");
+        }
+
+        if err_details.has_bad_request_violations() {
+            // Add aditional error details if necessary
+            err_details
+                .add_help_link("description of link", "https://resource.example.local")
+                .set_localized_message("en-US", "message for the user");
+
+            // Generate error status
+            let status = Status::with_error_details(
+                Code::InvalidArgument,
+                "request contains invalid arguments",
+                err_details,
+            );
+
+            return Err(status);
+        }
+
+        let reply = hello_world::HelloReply {
+            message: format!("Hello {}!", name),
+        };
+        Ok(Response::new(reply))
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let addr = "[::1]:50051".parse().unwrap();
+    let greeter = MyGreeter::default();
+
+    println!("GreeterServer listening on {}", addr);
+
+    Server::builder()
+        .add_service(GreeterServer::new(greeter))
+        .serve(addr)
+        .await?;
+
+    Ok(())
+}

examples/src/richer-error/server_vec.rs

@@ -0,0 +1,71 @@
+use tonic::{transport::Server, Code, Request, Response, Status};
+use tonic_types::{BadRequest, Help, LocalizedMessage, StatusExt};
+
+use hello_world::greeter_server::{Greeter, GreeterServer};
+use hello_world::{HelloReply, HelloRequest};
+
+pub mod hello_world {
+    tonic::include_proto!("helloworld");
+}
+
+#[derive(Default)]
+pub struct MyGreeter {}
+
+#[tonic::async_trait]
+impl Greeter for MyGreeter {
+    async fn say_hello(
+        &self,
+        request: Request<HelloRequest>,
+    ) -> Result<Response<HelloReply>, Status> {
+        println!("Got a request from {:?}", request.remote_addr());
+
+        // Extract request data
+        let name = request.into_inner().name;
+
+        // Create empty BadRequest struct
+        let mut bad_request = BadRequest::new(vec![]);
+
+        // Add violations conditionally
+        if name.is_empty() {
+            bad_request.add_violation("name", "name cannot be empty");
+        } else if name.len() > 20 {
+            bad_request.add_violation("name", "name is too long");
+        }
+
+        if !bad_request.is_empty() {
+            // Add aditional error details if necessary
+            let help = Help::with_link("description of link", "https://resource.example.local");
+
+            let localized_message = LocalizedMessage::new("en-US", "message for the user");
+
+            // Generate error status
+            let status = Status::with_error_details_vec(
+                Code::InvalidArgument,
+                "request contains invalid arguments",
+                vec![bad_request.into(), help.into(), localized_message.into()],
+            );
+
+            return Err(status);
+        }
+
+        let reply = hello_world::HelloReply {
+            message: format!("Hello {}!", name),
+        };
+        Ok(Response::new(reply))
+    }
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let addr = "[::1]:50051".parse().unwrap();
+    let greeter = MyGreeter::default();
+
+    println!("GreeterServer listening on {}", addr);
+
+    Server::builder()
+        .add_service(GreeterServer::new(greeter))
+        .serve(addr)
+        .await?;
+
+    Ok(())
+}