Struct Options 

#[non_exhaustive]
pub struct Options {
    pub buffa: CodeGenConfig,
    pub gate_client_feature: bool,
    pub client_feature_name: String,
    pub encodable_impls: EncodableImpls,
}

Options for ConnectRPC code generation.

These control both the underlying buffa message generation and the ConnectRPC service binding generation.

Construct via Options::default() then set fields on buffa directly (the struct is #[non_exhaustive], so struct-update syntax is unavailable from outside this crate).

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

buffa: CodeGenConfig

The underlying buffa-codegen configuration. Set any CodeGenConfig field directly here; connectrpc passes it through verbatim except for CodeGenConfig::generate_views, which is forced to true (service stubs require view types).

Options::default() starts from buffa’s defaults but enables generate_json (the Connect protocol’s JSON codec needs it; buffa’s own default is false).

buffa.extern_paths is used by generate_services to bake absolute paths into service stubs (set a (".", "crate::proto") catch-all so every type resolves); it is ignored by generate_files (the unified super::-relative path).

Every extern_path target must be buffa-generated code from buffa ≥ 0.8.0 with views enabled (and, if the crate feature-gates its generated impls, with that feature turned on): the service stubs rely on the buffa::HasMessageView impls and FooOwnedView wrappers emitted alongside each message, the same way they rely on the JSON/Serialize impls. buffa-types 0.8+ satisfies this for the well-known types. A crate generated without them fails to compile against the stubs (missing HasMessageView impl).

gate_client_feature: bool

When true, prefix every emitted FooClient<T> struct and its impl block with #[cfg(feature = "...")]. Opt in when the consuming crate wants to give server-only deployments a way to drop the client transport stack from their dependency graph.

client_feature_name: String

Cargo feature name used when Options::gate_client_feature is enabled (default: "client").

encodable_impls: EncodableImpls

Which messages get generated ::connectrpc::Encodable view impl pairs (default: EncodableImpls::Outputs, plugin opt encodable_impls=<all_messages|outputs>).

EncodableImpls::AllMessages emits the pair for every message defined in each targeted proto and emits companion files even for protos that declare no services. Use it in the generation run of a crate that owns message types consumed by other crates’ services (a shared proto crate in a multi-crate split). Rust’s orphan rules require the impl Encodable<M> for MView<'_> blocks to live in the crate that defines the view type, so a downstream service crate cannot emit them itself — its stubs skip foreign (::-rooted extern_path) types and handlers fall back to owned returns or PreEncoded::from_view. With the impls in the owning crate, those handlers can return views of the shared types directly (proto codec only — like every view body, they answer JSON-codec requests with Unimplemented).

The emitting crate must depend on connectrpc, and the companion files emitted for service-less packages must be mounted into the module tree like any other plugin output — an unmounted companion surfaces as a missing Encodable impl in the consuming crate. Messages mapped away via extern_paths are skipped, but only ::-rooted targets are recognized as foreign — a crate::-rooted re-export of another crate’s types would still get (orphan) impls. Synthetic map-entry messages never get impls.

Enabling this in a service crate’s own run is harmless (impls dedup within one run), but do not enable it in two generation runs that feed one crate and cover the same protos — each run emits its own copy of the impls (E0119).

Trait Implementations

impl Clone for Options

fn clone(&self) -> Options

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Options

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Options

fn default() -> Self

Returns the “default value” for a type.