structured-proxy 5.0.0

//! Universal gRPC→REST transcoding proxy — standalone binary.
//!
//! ```bash
//! structured-proxy --config proxy.yaml
//! ```

mod runtime;

use anyhow::Context as _;
use clap::Parser;
use tracing_subscriber::EnvFilter;

#[derive(Parser)]
#[command(
    name = "structured-proxy",
    version,
    about = "Universal gRPC→REST transcoding proxy"
)]
struct Cli {
    /// Path to YAML config file.
    #[arg(short, long, default_value = "proxy.yaml")]
    config: String,
}

fn main() -> anyhow::Result<()> {
    tracing_subscriber::fmt()
        .with_env_filter(EnvFilter::from_default_env())
        .init();

    let cli = Cli::parse();
    let yaml = std::fs::read_to_string(&cli.config)
        .with_context(|| format!("loading config {}", cli.config))?;
    // Reads the ProxyConfig and the transcoding settings kept outside it
    // (error_details, streaming.ndjson_envelope) from the same file. Loading
    // does no async work, so the runtime is built afterwards, from the same
    // file's `runtime:` section.
    let server = structured_proxy::ProxyServer::from_yaml_str(&yaml)
        .with_context(|| format!("loading config {}", cli.config))?;
    let file = runtime::FileConfig::from_yaml_str(&yaml)
        .with_context(|| format!("loading config {}", cli.config))?;
    let (rt, source) = file.runtime.build().context("starting the async runtime")?;

    let config = server.config();
    tracing::info!(
        service = %config.service.name,
        listen = %config.listen.http,
        upstream = %config.upstream.default,
        descriptors = config.descriptors.len(),
        worker_threads = rt.metrics().num_workers(),
        worker_threads_from = %source,
        "Starting structured-proxy"
    );

    rt.block_on(server.serve())
}