Automatically include copyright headers in generated files

Author: benthecarman

CONTRIBUTING.md

@@ -41,24 +41,9 @@ cargo clippy --all-features -- -D warnings -A clippy::drop_non_drop  # Lint (CI
 
 ```bash
 RUSTFLAGS="--cfg genproto" cargo build -p ldk-server-protos
+cargo fmt --all
 ```
 
-After regenerating, you must manually readd the copyright header to each generated file in `ldk-server-protos/src/` (
-`api.rs`, `types.rs`, `events.rs`, `error.rs`):
-
-```
-// This file is Copyright its original authors, visible in version control
-// history.
-//
-// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
-// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
-// You may not use this file except in accordance with one or both of these
-// licenses.
-```
-
-Then run `cargo fmt --all` to format the generated code.
-
 ## Adding a New API Endpoint
 
 1. Define request/response messages in `ldk-server-protos/src/proto/api.proto`

ldk-server-protos/build.rs

@@ -13,6 +13,19 @@ extern crate prost_build;
 #[cfg(genproto)]
 use std::{env, fs, path::Path};
 
+#[cfg(genproto)]
+const COPYRIGHT_HEADER: &str =
+	"// This file is Copyright its original authors, visible in version control
+// history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
+// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
+// You may not use this file except in accordance with one or both of these
+// licenses.
+
+";
+
 /// To generate updated proto objects, run `RUSTFLAGS="--cfg genproto" cargo build`
 fn main() {
 	#[cfg(genproto)]
@@ -38,13 +51,12 @@ fn generate_protos() {
 			&["src/proto/"],
 		)
 		.expect("protobuf compilation failed");
-	println!("OUT_DIR: {}", &env::var("OUT_DIR").unwrap());
-	let from_path = Path::new(&env::var("OUT_DIR").unwrap()).join("api.rs");
-	fs::copy(from_path, "src/api.rs").unwrap();
-	let from_path = Path::new(&env::var("OUT_DIR").unwrap()).join("types.rs");
-	fs::copy(from_path, "src/types.rs").unwrap();
-	let from_path = Path::new(&env::var("OUT_DIR").unwrap()).join("events.rs");
-	fs::copy(from_path, "src/events.rs").unwrap();
-	let from_path = Path::new(&env::var("OUT_DIR").unwrap()).join("error.rs");
-	fs::copy(from_path, "src/error.rs").unwrap();
+	let out_dir = env::var("OUT_DIR").unwrap();
+	println!("OUT_DIR: {}", &out_dir);
+	for file in &["api.rs", "types.rs", "events.rs", "error.rs"] {
+		let from_path = Path::new(&out_dir).join(file);
+		let content = fs::read_to_string(&from_path).unwrap();
+		let with_header = format!("{}{}", COPYRIGHT_HEADER, content);
+		fs::write(Path::new("src").join(file), with_header).unwrap();
+	}
 }