foxhunt/services/api_gateway/build.rs

//! Build script for API Gateway service
//!
//! Compiles protobuf definitions from the canonical proto/ directory at workspace root.
//! Proto packages:
//! - `foxhunt.tli` (fxt_trading.proto) - Fat-client unified interface (server+client)
//! - `trading` (trading.proto) - Backend trading service (client-only)
//! - `foxhunt.config` (config_service.proto) - Config service (server+client)
//! - `risk` (risk.proto) - Risk service (client-only)
//! - `monitoring` (monitoring.proto) - Monitoring service (server+client)
//! - `config` (config.proto) - Config backend (client-only)
//! - `ml_training` (ml_training.proto) - ML Training service (server+client)
//! - `trading_agent` (trading_agent.proto) - Trading Agent service (server+client)

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // NOTE: Tonic 0.14+ uses tonic_prost_build instead of tonic_build
    let config = tonic_prost_build::configure();

    let out_dir = std::path::PathBuf::from(std::env::var("OUT_DIR")?);

    // Compile Config Service proto (foxhunt.config package)
    config
        .clone()
        .build_server(true)
        .build_client(true)
        .file_descriptor_set_path(out_dir.join("config_service_descriptor.bin"))
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(&["../../proto/config_service.proto"], &["../../proto"])?;

    // Compile fat-client TLI proto (package: foxhunt.tli) — server+client
    // Contains TradingService, BacktestingService, and MLService
    // API Gateway acts as server for incoming client requests
    config
        .clone()
        .build_server(true)
        .build_client(true)
        .file_descriptor_set_path(out_dir.join("tli_descriptor.bin"))
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/fxt_trading.proto"],
            &["../../proto"],
        )?;

    // Compile Trading Service backend proto (package: trading) — client-only
    // API Gateway forwards translated requests to Trading Service
    config
        .clone()
        .build_server(false)
        .build_client(true)
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/trading.proto"],
            &["../../proto"],
        )?;

    // Compile Risk Service proto (package: risk) — client-only
    config
        .clone()
        .build_server(false)
        .build_client(true)
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/risk.proto"],
            &["../../proto"],
        )?;

    // Compile Monitoring Service proto (package: monitoring) — server+client
    config
        .clone()
        .build_server(true)
        .build_client(true)
        .file_descriptor_set_path(out_dir.join("monitoring_descriptor.bin"))
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/monitoring.proto"],
            &["../../proto"],
        )?;

    // Compile Config backend proto (package: config) — client-only
    config
        .clone()
        .build_server(false)
        .build_client(true)
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/config.proto"],
            &["../../proto"],
        )?;

    // Compile ML Training Service proto (package: ml_training) — server+client
    config
        .clone()
        .build_server(true)
        .build_client(true)
        .file_descriptor_set_path(out_dir.join("ml_training_descriptor.bin"))
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/ml_training.proto"],
            &["../../proto"],
        )?;

    // Compile Trading Agent Service proto (package: trading_agent) — server+client
    config
        .build_server(true)
        .build_client(true)
        .file_descriptor_set_path(out_dir.join("trading_agent_descriptor.bin"))
        .compile_well_known_types(true)
        .extern_path(".google.protobuf", "::prost_types")
        .type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]")
        .server_mod_attribute(".", "#[allow(unused_qualifications)]")
        .client_mod_attribute(".", "#[allow(unused_qualifications)]")
        .compile_protos(
            &["../../proto/trading_agent.proto"],
            &["../../proto"],
        )?;

    println!("cargo:rerun-if-changed=../../proto/config_service.proto");
    println!("cargo:rerun-if-changed=../../proto/fxt_trading.proto");
    println!("cargo:rerun-if-changed=../../proto/trading.proto");
    println!("cargo:rerun-if-changed=../../proto/risk.proto");
    println!("cargo:rerun-if-changed=../../proto/monitoring.proto");
    println!("cargo:rerun-if-changed=../../proto/config.proto");
    println!("cargo:rerun-if-changed=../../proto/ml_training.proto");
    println!("cargo:rerun-if-changed=../../proto/trading_agent.proto");

    Ok(())
}