build.rs

// Copyright Istio 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.

use std::env;
use std::process::Command;

// This build script is used to generate the rust source files that
// we need for XDS GRPC communication.
fn main() -> Result<(), anyhow::Error> {
    // Fuzzing uses custom cfg (https://rust-fuzz.github.io/book/cargo-fuzz/guide.html)
    // Tell cargo to expect this (https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html).
    println!("cargo::rustc-check-cfg=cfg(fuzzing)");
    let proto_files = [
        "proto/xds.proto",
        "proto/workload.proto",
        "proto/authorization.proto",
        "proto/citadel.proto",
        "proto/zds.proto",
    ]
    .iter()
    .map(|name| std::env::current_dir().unwrap().join(name))
    .collect::<Vec<_>>();
    let include_dirs = ["proto/"]
        .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.bytes([
            ".istio.workload.Workload",
            ".istio.workload.Service",
            ".istio.workload.GatewayAddress",
            ".istio.workload.Address",
            ".istio.security.Address",
        ]);
        c
    };
    tonic_build::configure()
        .build_server(true)
        .compile_protos_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 [proto_files, include_dirs].concat() {
        println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
    }

    // Adoppted from https://github.com/uutils/coreutils/blob/main/src/uu/stdbuf/build.rs
    let out_dir = env::var("OUT_DIR").unwrap();
    let profile_name = out_dir
        .split(std::path::MAIN_SEPARATOR)
        .nth_back(3)
        .unwrap();

    match Command::new("common/scripts/report_build_info.sh").output() {
        Ok(output) => {
            for line in String::from_utf8(output.stdout).unwrap().lines() {
                // Each line looks like `istio.io/pkg/version.buildGitRevision=abc`
                if let Some((key, value)) = line.split_once('=') {
                    let key = key.split('.').last().unwrap();
                    println!("cargo:rustc-env=ZTUNNEL_BUILD_{key}={value}");
                } else {
                    println!("cargo:warning=invalid build output {line}");
                }
            }
        }
        Err(err) => {
            println!("cargo:warning={err}");
        }
    };
    println!(
        "cargo:rustc-env=ZTUNNEL_BUILD_RUSTC_VERSION={}",
        rustc_version::version().unwrap()
    );
    println!(
        "cargo:rustc-env=ZTUNNEL_BUILD_PROFILE_NAME={}",
        profile_name
    );
    Ok(())
}