build.rs

/*
 * Copyright 2020 Google LLC
 *
 * 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.
 */

// This build script is used to generate the rust source files that
// we need for XDS GRPC communication.
fn main() -> Result<(), Box<dyn std::error::Error>> {
    #[cfg(feature = "vendor-protoc")]
    std::env::set_var("PROTOC", protobuf_src::protoc());

    let proto_files = vec![
        "proto/data-plane-api/envoy/config/common/matcher/v3/matcher.proto",
        "proto/data-plane-api/envoy/config/accesslog/v3/accesslog.proto",
        "proto/data-plane-api/envoy/config/cluster/v3/cluster.proto",
        "proto/data-plane-api/envoy/config/listener/v3/listener.proto",
        "proto/data-plane-api/envoy/config/listener/v3/listener_components.proto",
        "proto/data-plane-api/envoy/config/route/v3/route.proto",
        "proto/data-plane-api/envoy/service/cluster/v3/cds.proto",
        "proto/data-plane-api/envoy/service/discovery/v3/ads.proto",
        "proto/data-plane-api/envoy/service/discovery/v3/discovery.proto",
        "proto/data-plane-api/envoy/type/metadata/v3/metadata.proto",
        "proto/data-plane-api/envoy/type/tracing/v3/custom_tag.proto",
        "proto/quilkin/filters/capture/v1alpha1/capture.proto",
        "proto/quilkin/filters/compress/v1alpha1/compress.proto",
        "proto/quilkin/filters/concatenate_bytes/v1alpha1/concatenate_bytes.proto",
        "proto/quilkin/filters/debug/v1alpha1/debug.proto",
        "proto/quilkin/filters/drop/v1alpha1/drop.proto",
        "proto/quilkin/filters/firewall/v1alpha1/firewall.proto",
        "proto/quilkin/filters/load_balancer/v1alpha1/load_balancer.proto",
        "proto/quilkin/filters/local_rate_limit/v1alpha1/local_rate_limit.proto",
        "proto/quilkin/filters/match/v1alpha1/match.proto",
        "proto/quilkin/filters/pass/v1alpha1/pass.proto",
        "proto/quilkin/filters/token_router/v1alpha1/token_router.proto",
        "proto/quilkin/filters/timestamp/v1alpha1/timestamp.proto",
        "proto/udpa/xds/core/v3/resource_name.proto",
    ]
    .iter()
    .map(|name| std::env::current_dir().unwrap().join(name))
    .collect::<Vec<_>>();

    let include_dirs = vec![
        "proto/data-plane-api",
        "proto/udpa",
        "proto/googleapis",
        "proto/protoc-gen-validate",
        "proto/quilkin",
    ]
    .iter()
    .map(|i| std::env::current_dir().unwrap().join(i))
    .collect::<Vec<_>>();

    let config = {
        let mut c = prost_build::Config::new();
        c.disable_comments(Some("."));
        c
    };
    tonic_build::configure()
        .build_server(true)
        .compile_with_config(
            config,
            &proto_files
                .iter()
                .map(|path| path.to_str().unwrap())
                .collect::<Vec<_>>(),
            &include_dirs
                .iter()
                .map(|p| p.to_str().unwrap())
                .collect::<Vec<_>>(),
        )?;

    // This tells cargo to re-run this build script only when the proto files
    // we're interested in change or the any of the proto directories were updated.
    for path in vec![proto_files, include_dirs].concat() {
        println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
    }

    built::write_built_file().expect("Failed to acquire build-time information");

    Ok(())
}