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use std::net::SocketAddr;
use std::path::PathBuf;
use clap::{Args, Subcommand, ValueEnum};
use super::ProfileArgs;
/// Observability dev-routing chosen at server startup. Maps to a single
/// concrete backend installed via
/// [`harn_vm::install_obs_default_backend`] before any handler runs;
/// `.harn` code can still override this with `obs.configure(...)` at
/// runtime.
#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum, Default)]
#[clap(rename_all = "snake_case")]
pub(crate) enum ServeObsMode {
/// Resolve from environment variables (`OTEL_EXPORTER_OTLP_ENDPOINT`,
/// `HONEYCOMB_API_KEY`, etc.) the same way `obs.auto_backend()` does.
#[default]
Auto,
/// Pretty-print spans/metrics/logs to stdout. Convenient for local
/// development where you want the server output in the same stream
/// as the rest of the .harn handler's logs.
Stdout,
/// Pretty-print to stderr — keeps stdout clean for response bodies
/// or piping handler output into another tool.
Stderr,
/// Force the OTel exporter even if no env-var is set. Falls back to
/// the OpenTelemetry SDK default endpoint (`localhost:4318`).
Otel,
/// Disable observability emission entirely — primitive events still
/// touch the in-process buffer (so `obs.events()` works for tests)
/// but nothing leaves the process.
Off,
}
#[derive(Debug, Args)]
pub(crate) struct ServeArgs {
#[command(subcommand)]
pub command: ServeCommand,
}
#[derive(Debug, Subcommand)]
pub(crate) enum ServeCommand {
/// Serve a .harn agent over stdio using ACP.
Acp(ServeAcpArgs),
/// Serve a .harn agent over HTTP using A2A.
A2a(A2aServeArgs),
/// Serve a `.harn` agent over the local Harn Agents HTTP API.
Api(ApiServeArgs),
/// Serve a `.harn` file as an MCP server. Exposes either exported
/// `pub fn` entrypoints (recommended) or, when the script registers
/// tools/resources/prompts via `mcp_tools(...)` / `mcp_resource(...)`
/// / `mcp_prompt(...)`, that script-driven surface.
Mcp(ServeMcpArgs),
}
#[derive(Debug, Args)]
pub(crate) struct ServeAcpArgs {
/// Static API keys accepted by the ACP authenticate method.
#[arg(long = "api-key", env = "HARN_SERVE_API_KEY", value_delimiter = ',')]
pub api_key: Vec<String>,
/// Shared secret for HMAC authentication through the ACP authenticate method.
#[arg(long = "hmac-secret", env = "HARN_SERVE_HMAC_SECRET")]
pub hmac_secret: Option<String>,
/// Enable LLM trace summaries on shutdown.
#[arg(
long = "trace",
env = "HARN_TRACE",
action = clap::ArgAction::SetTrue,
value_parser = clap::builder::BoolishValueParser::new()
)]
pub trace: bool,
/// Where to route `harness.obs.*` spans/metrics/logs.
#[arg(long = "obs", value_enum, default_value_t = ServeObsMode::Auto)]
pub obs: ServeObsMode,
#[command(flatten)]
pub profile: ProfileArgs,
/// Path to the .harn file to serve.
pub file: String,
}
#[derive(Debug, Args)]
pub(crate) struct A2aServeArgs {
/// Socket address to bind the A2A server to. Defaults to loopback; use
/// `--bind 0.0.0.0:PORT` only behind explicit auth/TLS or a trusted edge.
#[arg(long, env = "HARN_SERVE_A2A_BIND", value_name = "ADDR")]
pub bind: Option<SocketAddr>,
/// Port to bind the A2A server to.
#[arg(long, default_value_t = 8080)]
pub port: u16,
/// Public URL advertised in the A2A agent card.
#[arg(long = "public-url", env = "HARN_SERVE_A2A_PUBLIC_URL")]
pub public_url: Option<String>,
/// Static API keys accepted via `Authorization: Bearer` or `X-API-Key`.
#[arg(long = "api-key", env = "HARN_SERVE_API_KEY", value_delimiter = ',')]
pub api_key: Vec<String>,
/// Shared secret for HMAC request signing.
#[arg(long = "hmac-secret", env = "HARN_SERVE_HMAC_SECRET")]
pub hmac_secret: Option<String>,
/// Shared secret used to attach an HS256 signature to the agent card.
#[arg(long = "card-signing-secret", env = "HARN_SERVE_A2A_CARD_SECRET")]
pub card_signing_secret: Option<String>,
/// TLS listener mode. Supplying both `--cert` and `--key` implies `pem`.
#[arg(long = "tls", value_enum, default_value_t = ServeTlsMode::Plain)]
pub tls: ServeTlsMode,
/// PEM-encoded certificate chain for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_CERT", value_name = "PATH")]
pub cert: Option<PathBuf>,
/// PEM-encoded private key for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_KEY", value_name = "PATH")]
pub key: Option<PathBuf>,
/// Where to route `harness.obs.*` spans/metrics/logs.
#[arg(long = "obs", value_enum, default_value_t = ServeObsMode::Auto)]
pub obs: ServeObsMode,
/// Path to the .harn file to serve.
pub file: String,
}
#[derive(Debug, Args)]
pub(crate) struct ApiServeArgs {
/// Socket address to bind the local Agents API server to.
#[arg(
long,
env = "HARN_SERVE_API_BIND",
default_value = "127.0.0.1:8787",
value_name = "ADDR"
)]
pub bind: SocketAddr,
/// Public URL printed and advertised for the local API server.
#[arg(long = "public-url", env = "HARN_SERVE_API_PUBLIC_URL")]
pub public_url: Option<String>,
/// Static API keys accepted via `Authorization: Bearer` or `X-API-Key`.
#[arg(long = "api-key", env = "HARN_SERVE_API_KEY", value_delimiter = ',')]
pub api_key: Vec<String>,
/// Shared secret for HMAC request signing.
#[arg(long = "hmac-secret", env = "HARN_SERVE_HMAC_SECRET")]
pub hmac_secret: Option<String>,
/// TLS listener mode. Supplying both `--cert` and `--key` implies `pem`.
#[arg(long = "tls", value_enum, default_value_t = ServeTlsMode::Plain)]
pub tls: ServeTlsMode,
/// PEM-encoded certificate chain for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_CERT", value_name = "PATH")]
pub cert: Option<PathBuf>,
/// PEM-encoded private key for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_KEY", value_name = "PATH")]
pub key: Option<PathBuf>,
/// Enable LLM trace summaries on shutdown.
#[arg(
long = "trace",
env = "HARN_TRACE",
action = clap::ArgAction::SetTrue,
value_parser = clap::builder::BoolishValueParser::new()
)]
pub trace: bool,
/// Where to route `harness.obs.*` spans/metrics/logs.
#[arg(long = "obs", value_enum, default_value_t = ServeObsMode::Auto)]
pub obs: ServeObsMode,
#[command(flatten)]
pub profile: ProfileArgs,
/// Path to the `.harn` agent file to serve.
pub file: String,
}
#[derive(Debug, Args)]
pub(crate) struct ServeMcpArgs {
/// Transport to expose for MCP clients.
#[arg(long, value_enum, default_value_t = McpServeTransport::Stdio)]
pub transport: McpServeTransport,
/// Socket address to bind when serving over HTTP.
#[arg(
long,
env = "HARN_SERVE_MCP_BIND",
default_value = "127.0.0.1:8765",
value_name = "ADDR"
)]
pub bind: SocketAddr,
/// Streamable HTTP endpoint path.
#[arg(long, default_value = "/mcp", value_name = "PATH")]
pub path: String,
/// Legacy SSE endpoint path for older MCP clients.
#[arg(long = "sse-path", default_value = "/sse", value_name = "PATH")]
pub sse_path: String,
/// Legacy SSE POST endpoint path for older MCP clients.
#[arg(
long = "messages-path",
default_value = "/messages",
value_name = "PATH"
)]
pub messages_path: String,
/// Static API keys accepted over HTTP via `Authorization: Bearer` or `X-API-Key`.
#[arg(long = "api-key", env = "HARN_SERVE_API_KEY", value_delimiter = ',')]
pub api_key: Vec<String>,
/// Shared secret for HMAC request signing on HTTP transports.
#[arg(long = "hmac-secret", env = "HARN_SERVE_HMAC_SECRET")]
pub hmac_secret: Option<String>,
/// TLS listener mode. Supplying both `--cert` and `--key` implies `pem`.
#[arg(long = "tls", value_enum, default_value_t = ServeTlsMode::Plain)]
pub tls: ServeTlsMode,
/// PEM-encoded certificate chain for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_CERT", value_name = "PATH")]
pub cert: Option<PathBuf>,
/// PEM-encoded private key for in-process HTTPS termination.
#[arg(long, env = "HARN_SERVE_KEY", value_name = "PATH")]
pub key: Option<PathBuf>,
/// Optional Server Card JSON to advertise (MCP v2.1). Path to a
/// `.json` file OR an inline JSON string. The card is embedded in
/// the `initialize` response's `serverInfo.card` field AND exposed
/// as a static resource at `well-known://mcp-card`.
#[arg(long = "card", value_name = "PATH_OR_JSON")]
pub card: Option<String>,
/// Where to route `harness.obs.*` spans/metrics/logs.
#[arg(long = "obs", value_enum, default_value_t = ServeObsMode::Auto)]
pub obs: ServeObsMode,
/// Path to the `.harn` file whose exported `pub fn` entrypoints are
/// served. Scripts that instead call `mcp_tools(registry)` /
/// `mcp_resource(...)` / `mcp_prompt(...)` are detected and served
/// via the script-driven surface.
pub file: String,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum)]
pub(crate) enum McpServeTransport {
Stdio,
Http,
}
#[derive(Debug, Clone, Copy, PartialEq, Eq, ValueEnum)]
pub(crate) enum ServeTlsMode {
Plain,
Edge,
SelfSignedDev,
Pem,
}