gRPC sample with *all* the streams

Cargo.toml

@@ -2,6 +2,7 @@
 resolver = "2"
 members = [
   "examples/grpc",
+  "examples/grpc-streaming",
   "examples/hello-world",
   "examples/http-axum-router",
   "examples/http-concurrent-outbound-calls",

examples/grpc-streaming/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "grpc-streaming"
+version = "0.1.0"
+edition = "2024"
+
+[lib]
+crate-type = ["cdylib"]
+
+[dependencies]
+anyhow = "1"
+async-stream = "0.3"
+futures = "0.3"
+prost = "0.13"
+spin-sdk = { path = "../../crates/spin-sdk", features = ["grpc"] }
+tokio-stream = "0.1"
+tonic = { version = "0.12", default-features = false, features = ["codegen", "prost", "router"] }
+
+[build-dependencies]
+tonic-build = { version = "0.12", default-features = false, features = ["prost"] }

examples/grpc-streaming/README.md

@@ -0,0 +1,48 @@
+# gRPC Streaming
+
+A Spin HTTP component that serves gRPC endpoints using [tonic](https://github.com/hyperium/tonic),
+demonstrating all combinations of unary and streaming requests and responses.
+
+## Prerequisites
+
+- [protoc](https://grpc.io/docs/protoc-installation/) (Protocol Buffers compiler)
+- `wasm32-wasip2` target: `rustup target add wasm32-wasip2`
+
+## Build and Run
+
+```sh
+spin up --build --sqlite @db.sql
+```
+
+## Test with grpcurl
+
+> **Note:** These commands pass `-import-path` and `-proto` because the server
+> does not implement gRPC server reflection.
+
+Unary call:
+
+```sh
+grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"latitude":18,"longitude":19}' localhost:3000 routeguide.RouteGuide/GetFeature
+```
+
+Server-streaming call:
+
+```sh
+ grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"lo":{"latitude":12,"longitude":10},"hi":{"latitude":28,"longitude":25}}' localhost:3000 routeguide.RouteGuide/ListFeatures
+```
+
+Client-streaming call:
+
+```sh
+grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"latitude":18,"longitude":19}{"latitude":12,"longitude":20}{"latitude":13,"longitude":17}{"latitude":14,"longitude":18}' localhost:3000 routeguide.RouteGuide/RecordRoute
+```
+
+Client- and server-streaming:
+
+```sh
+grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"location":{"latitude":18,"longitude":19},"message":"hello from fang rock!"}{"location":{"latitude":12,"longitude":20},"message":"i summited mt hobbes!"}' localhost:3000 routeguide.RouteGuide/RouteChat
+grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"location":{"latitude":18,"longitude":19},"message":"farewell from fang rock!"}' localhost:3000 routeguide.RouteGuide/RouteChat
+grpcurl -plaintext -import-path proto -proto route_guide.proto -d '{"location":{"latitude":12,"longitude":20},"message":"i was impaled on sharp claws at mt hobbes!"}{"location":{"latitude":18,"longitude":19},"message":"i got nibbled by rutans at fang rock!"}' localhost:3000 routeguide.RouteGuide/RouteChat
+```
+
+(Multiple commands because the routeguide scenario needs you to build up some history at a location to see interesting responses.)

examples/grpc-streaming/build.rs

@@ -0,0 +1,7 @@
+fn main() {
+    tonic_build::configure()
+        .type_attribute("routeguide.Point", "#[derive(Hash)]")
+        .build_transport(false)
+        .compile_protos(&["proto/route_guide.proto"], &[""])
+        .unwrap();
+}

examples/grpc-streaming/db.sql

@@ -0,0 +1,21 @@
+CREATE TABLE IF NOT EXISTS features (
+    lat NUMBER,
+    long NUMBER,
+    name TEXT
+);
+
+DELETE FROM features;
+INSERT INTO features(lat, long, name) VALUES (12, 20, 'Mount Hobbes');
+INSERT INTO features(lat, long, name) VALUES (30, 8, 'Upper Rosie');
+INSERT INTO features(lat, long, name) VALUES (14, 18, 'Slats'' Food Crater');
+INSERT INTO features(lat, long, name) VALUES (25, 30, 'Forest of Smoke');
+INSERT INTO features(lat, long, name) VALUES (22, 7, 'The Great Splodge');
+INSERT INTO features(lat, long, name) VALUES (35, 21, 'Kiki Point');
+INSERT INTO features(lat, long, name) VALUES (18, 19, 'Fang Rock');
+
+CREATE TABLE IF NOT EXISTS route_notes(
+    seq_no INTEGER PRIMARY KEY AUTOINCREMENT,
+    lat NUMBER,
+    long NUMBER,
+    msg_text TEXT
+);

examples/grpc-streaming/proto/route_guide.proto

@@ -0,0 +1,110 @@
+// Copyright 2015 gRPC authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "io.grpc.examples.routeguide";
+option java_outer_classname = "RouteGuideProto";
+
+package routeguide;
+
+// Interface exported by the server.
+service RouteGuide {
+  // A simple RPC.
+  //
+  // Obtains the feature at a given position.
+  //
+  // A feature with an empty name is returned if there's no feature at the given
+  // position.
+  rpc GetFeature(Point) returns (Feature) {}
+
+  // A server-to-client streaming RPC.
+  //
+  // Obtains the Features available within the given Rectangle.  Results are
+  // streamed rather than returned at once (e.g. in a response message with a
+  // repeated field), as the rectangle may cover a large area and contain a
+  // huge number of features.
+  rpc ListFeatures(Rectangle) returns (stream Feature) {}
+
+  // A client-to-server streaming RPC.
+  //
+  // Accepts a stream of Points on a route being traversed, returning a
+  // RouteSummary when traversal is completed.
+  rpc RecordRoute(stream Point) returns (RouteSummary) {}
+
+  // A Bidirectional streaming RPC.
+  //
+  // Accepts a stream of RouteNotes sent while a route is being traversed,
+  // while receiving other RouteNotes (e.g. from other users).
+  rpc RouteChat(stream RouteNote) returns (stream RouteNote) {}
+}
+
+// Points are represented as latitude-longitude pairs in the E7 representation
+// (degrees multiplied by 10**7 and rounded to the nearest integer).
+// Latitudes should be in the range +/- 90 degrees and longitude should be in
+// the range +/- 180 degrees (inclusive).
+message Point {
+  int32 latitude = 1;
+  int32 longitude = 2;
+}
+
+// A latitude-longitude rectangle, represented as two diagonally opposite
+// points "lo" and "hi".
+message Rectangle {
+  // One corner of the rectangle.
+  Point lo = 1;
+
+  // The other corner of the rectangle.
+  Point hi = 2;
+}
+
+// A feature names something at a given point.
+//
+// If a feature could not be named, the name is empty.
+message Feature {
+  // The name of the feature.
+  string name = 1;
+
+  // The point where the feature is detected.
+  Point location = 2;
+}
+
+// A RouteNote is a message sent while at a given point.
+message RouteNote {
+  // The location from which the message is sent.
+  Point location = 1;
+
+  // The message to be sent.
+  string message = 2;
+}
+
+// A RouteSummary is received in response to a RecordRoute rpc.
+//
+// It contains the number of individual points received, the number of
+// detected features, and the total distance covered as the cumulative sum of
+// the distance between each point.
+message RouteSummary {
+  // The number of points received.
+  int32 point_count = 1;
+
+  // The number of known features passed while traversing the route.
+  int32 feature_count = 2;
+
+  // The distance covered in metres.
+  int32 distance = 3;
+
+  // The duration of the traversal in seconds.
+  int32 elapsed_time = 4;
+}