azure-functions-shared 0.6.0

use std::env;
use std::fs;
use std::path::PathBuf;

const OUT_DIR_VAR: &str = "OUT_DIR";
const CACHE_DIR_NAME: &str = "cache";
const PROTOBUF_INPUT_FILES: &[&str] = &["FunctionRpc.proto", "identity/ClaimsIdentityRpc.proto"];
const OUTPUT_FILES: &[&str] = &[
    "FunctionRpc.rs",
    "FunctionRpc_grpc.rs",
    "ClaimsIdentityRpc.rs",
];

fn compile_protobufs(out_dir: &PathBuf, cache_dir: &PathBuf) {
    protoc_grpcio::compile_grpc_protos(
        PROTOBUF_INPUT_FILES,
        &["protobuf/src/proto"],
        &out_dir,
        None,
    )
    .expect("Failed to compile gRPC definitions.");

    for file in OUTPUT_FILES.iter() {
        fs::copy(out_dir.join(file), cache_dir.join(file))
            .expect(&format!("can't update cache file '{}'", file));
    }
}

fn use_cached_files(out_dir: &PathBuf, cache_dir: &PathBuf) {
    for file in OUTPUT_FILES.iter() {
        fs::copy(cache_dir.join(file), out_dir.join(file)).expect(&format!(
            "can't copy cache file '{}' to output directory",
            file
        ));
    }
}

fn main() {
    println!("cargo:rerun-if-changed=protobuf/src/proto/FunctionRpc.proto");

    let out_dir = PathBuf::from(env::var(OUT_DIR_VAR).unwrap());

    let cache_dir = env::current_dir()
        .expect("couldn't determine current working directory")
        .join(CACHE_DIR_NAME);

    fs::create_dir_all(&cache_dir).expect("failed to create cache directory");

    if cfg!(feature = "compile_protobufs") {
        compile_protobufs(&out_dir, &cache_dir);
    } else {
        use_cached_files(&out_dir, &cache_dir);
    }
}