feat(build): Support compiling well-known protobuf types (#522)

tests/wellknown-compiled/Cargo.toml

@@ -0,0 +1,19 @@
+[package]
+name = "wellknown-compiled"
+version = "0.1.0"
+authors = ["Lucio Franco <[email protected]>"]
+edition = "2018"
+publish = false
+license = "MIT"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[lib]
+doctest = false
+
+[dependencies]
+tonic = { path = "../../tonic" }
+prost = "0.7"
+
+[build-dependencies]
+tonic-build = { path = "../../tonic-build" }

tests/wellknown-compiled/build.rs

@@ -0,0 +1,6 @@
+fn main() {
+    tonic_build::configure()
+        .compile_well_known_types(true)
+        .compile(&["proto/google.proto"], &["proto"])
+        .unwrap();
+}

tests/wellknown-compiled/proto/google.proto

@@ -0,0 +1,16 @@
+syntax = "proto3";
+
+package google.protobuf;
+
+import "google/protobuf/any.proto";
+import "google/protobuf/api.proto";
+import "google/protobuf/descriptor.proto";
+import "google/protobuf/duration.proto";
+import "google/protobuf/empty.proto";
+import "google/protobuf/field_mask.proto";
+import "google/protobuf/source_context.proto";
+import "google/protobuf/struct.proto";
+import "google/protobuf/timestamp.proto";
+import "google/protobuf/type.proto";
+import "google/protobuf/wrappers.proto";
+

tests/wellknown-compiled/src/lib.rs

@@ -0,0 +1,9 @@
+pub mod google {
+    pub mod protobuf {
+        tonic::include_proto!("google.protobuf");
+    }
+}
+
+pub fn grok() {
+    let _empty = crate::google::protobuf::Empty {};
+}