canton 0.2.3

The Canton Network Rust SDK: one-stop entry point re-exporting the canton-* crate family.
Documentation 
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//! The Canton Network Rust SDK — one-stop entry point.
//!
//! This crate is a thin facade over the `canton-*` family: it contains no
//! logic of its own, only re-exports, so `cargo add canton` brings in the
//! whole SDK as one coherent, version-locked set. Each member crate can also
//! be used directly (`cargo add canton-ledger`) when only a subset is needed.
//!
//! | Module | Crate | What it is |
//! |---|---|---|
//! | [`ledger`] | `canton-ledger` | The async Ledger API v2 client (gRPC + JSON + WebSocket) |
//! | [`auth`] | `canton-auth` | JWT/OIDC authentication (client-credentials, caching, refresh) |
//! | [`admin`] | `canton-admin` | Party management, user self-inspect, topology read |
//! | [`daml`] | `canton-daml` | The runtime under generated bindings: Daml primitives, codecs, command builders |
//!
//! The shared foundation (`canton-core`: [`Config`], [`Error`], TLS, retry)
//! is re-exported at the crate root — the same types `canton-ledger` itself
//! re-exports, so both entry points name identical items.
//!
//! # Typed bindings
//!
//! [`daml`] is the runtime half of the codegen story: generated bindings
//! depend on it (as `rt`) for [`daml::Party`], [`daml::ContractId`], the
//! `Template`/`Choice` traits, and the command builders. It is re-exported
//! here so a `cargo add canton` user gets a version-locked runtime without a
//! second dependency line.
//!
//! Generating the bindings themselves is a **build-time** step, so the
//! generator is deliberately *not* re-exported: install the CLI with
//! `cargo install canton-codegen-cli`, or depend on `canton-codegen` from a
//! build script.
//!
//! # Feature flags
//!
//! Features are forwarded to the crates that implement them:
//!
//! * `ws` — WebSocket streaming for the JSON transport (`canton-ledger/ws`).
//! * `otel` — OTLP export + W3C trace-context propagation (`canton-ledger/otel`).
//!
//! # Quickstart
//!
//! ```no_run
//! use canton::ledger::{CantonClient, Config};
//!
//! # async fn run() -> canton::Result<()> {
//! let client = CantonClient::connect_lazy(Config::new("http://localhost:3901"))?;
//! println!("ledger api version: {}", client.version().await?);
//! # Ok(())
//! # }
//! ```
//!
//! This SDK is a community project funded by Canton dev-fund proposal
//! [#407](https://github.com/canton-foundation/canton-dev-fund/pull/407);
//! it is not an official Digital Asset product.

pub use canton_admin as admin;
pub use canton_auth as auth;
pub use canton_daml as daml;
pub use canton_ledger as ledger;

/// Reading a local development network out of the environment — the variables
/// `canton-devkit localnet env` exports, and the party ids that come with them.
pub use canton_core::localnet;
/// What the SDK emits, and how to export it: the span and metric names, the
/// transport labels they carry, and — behind `otel` — the OTLP setup for both
/// signals. An application building a dashboard needs these, and reaching them
/// meant depending on `canton-core` directly, which `cargo add canton` does not
/// do.
pub use canton_core::telemetry;

pub use canton_core::{
    Auth, Config, Error, ErrorCategory, ErrorInfo, ResourceInfo, Result, RetryConfig, TlsConfig,
    TokenSource,
};

#[cfg(test)]
mod tests {
    //! What `cargo add canton` can actually reach.
    //!
    //! This crate is a facade, so its failure mode is silent: a type the SDK
    //! documents is simply not there under `canton::`, nothing fails to
    //! compile, and the first person to find out is a user following the
    //! README. These name the paths the documentation promises.

    #[test]
    fn the_client_surface_is_reachable_through_the_facade() {
        fn assert_named<T>() {}
        assert_named::<crate::ledger::CantonClient>();
        assert_named::<crate::ledger::JsonClient>();
        // The recovery handles and their identity — the answer to an ambiguous
        // submission, which is the one thing a caller cannot reconstruct.
        assert_named::<crate::ledger::Submission>();
        assert_named::<crate::ledger::JsonSubmission>();
        assert_named::<crate::ledger::ChangeId>();
        // The lossless ACS read.
        assert_named::<crate::ledger::AcsEntry>();
        assert_named::<crate::admin::AdminClient>();
        assert_named::<crate::auth::TokenProvider>();
        assert_named::<crate::auth::ClientAuth>();
    }

    #[test]
    fn the_telemetry_names_a_dashboard_is_built_from_are_reachable() {
        assert_eq!(crate::telemetry::TRANSPORT_GRPC, "grpc");
        assert_eq!(crate::telemetry::TRANSPORT_JSON, "json");
        assert!(crate::telemetry::METRIC_REQUESTS.starts_with("canton_client_"));
        assert!(crate::telemetry::METRIC_ERRORS.starts_with("canton_client_"));
    }

    /// The OTLP setup the documentation points an application at. Without the
    /// facade forwarding `canton-core/otel`, this module would not exist here
    /// even with `canton = { features = ["otel"] }`.
    #[cfg(feature = "otel")]
    #[test]
    fn the_otlp_setup_is_reachable_through_the_facade() {
        // Naming them is the assertion — calling them would need a collector.
        // An unreachable body type-checks the paths without opening a socket.
        fn _paths(endpoint: String) {
            let _ = crate::telemetry::otel::otlp_metrics("svc", endpoint.clone());
            let _ = crate::telemetry::otel::otlp_tracer_provider("svc", endpoint.clone());
            let _ = crate::telemetry::otel::otlp_tracer("svc", endpoint);
        }
    }
}