Struct Builder 

pub struct Builder { /* private fields */ }

Builder for compiling .proto files with reflection metadata enabled.

Driving the build script:

fn main() -> Result<(), Box<dyn std::error::Error>> {
    buffa_reflect_build::Builder::new()
        .file_descriptor_set_bytes("crate::FILE_DESCRIPTOR_SET_BYTES")
        .files(&["proto/acme/api/v1/user.proto"])
        .includes(&["proto/"])
        .compile()?;
    Ok(())
}

The downstream library then ships:

pub const FILE_DESCRIPTOR_SET_BYTES: &[u8] =
    include_bytes!(concat!(env!("OUT_DIR"), "/file_descriptor_set.bin"));

buffa::include_proto!("acme.api.v1");

Every generated message is decorated with #[derive(::buffa_reflect::ReflectMessage)] so that m.descriptor() resolves the right MessageDescriptor at runtime.

Implementations

impl Builder

pub fn new() -> Self

Construct a new builder with default settings.

pub fn descriptor_pool(self, expr: impl Into<String>) -> Self

Use a user-managed DescriptorPool for runtime descriptor lookup. The argument is a Rust expression yielding &buffa_reflect::DescriptorPool (e.g. "crate::DESCRIPTOR_POOL").

pub fn file_descriptor_set_bytes(self, expr: impl Into<String>) -> Self

Embed the descriptor-set bytes directly. The argument is a Rust expression yielding &[u8], typically "crate::FILE_DESCRIPTOR_SET_BYTES" paired with include_bytes!(concat!(env!("OUT_DIR"), "/file_descriptor_set.bin")).

pub fn file_descriptor_set_path(self, path: impl Into<PathBuf>) -> Self

Override where the descriptor-set artifact is written. Defaults to <OUT_DIR>/file_descriptor_set.bin.

pub fn files(self, files: &[impl AsRef<Path>]) -> Self

.proto files to compile. Same semantics as buffa_build::Config::files.

pub fn includes(self, includes: &[impl AsRef<Path>]) -> Self

Include directories searched by protoc.

pub fn use_buf(self) -> Self

Use buf build --as-file-descriptor-set instead of protoc.

pub fn descriptor_set(self, path: impl Into<PathBuf>) -> Self

Use a precompiled descriptor-set file. Skips invoking protoc/buf. The file must contain a serialized google.protobuf.FileDescriptorSet.

pub fn out_dir(self, dir: impl Into<PathBuf>) -> Self

Override the output directory (defaults to $OUT_DIR).

pub fn type_attribute( self, path: impl Into<String>, attr: impl Into<String>, ) -> Self

Pass a type_attribute through to buffa-build.

pub fn field_attribute( self, path: impl Into<String>, attr: impl Into<String>, ) -> Self

Pass a field_attribute through to buffa-build.

pub fn message_attribute( self, path: impl Into<String>, attr: impl Into<String>, ) -> Self

Pass a message_attribute through to buffa-build (struct-only).

pub fn enum_attribute( self, path: impl Into<String>, attr: impl Into<String>, ) -> Self

Pass an enum_attribute through to buffa-build (enum-only).

pub fn extern_path( self, proto_path: impl Into<String>, rust_path: impl Into<String>, ) -> Self

Map a proto path prefix to an external Rust module. Forwarded to buffa_build::Config::extern_path.

pub fn use_bytes_type_in(self, paths: &[impl AsRef<str>]) -> Self

Mark bytes fields under the given proto-path prefixes as bytes::Bytes-typed.

pub fn generate_views(self, enabled: bool) -> Self

Toggle generation of borrowed view types. Defaults to buffa-build’s own default (currently true).

pub fn generate_json(self, enabled: bool) -> Self

Toggle proto3 JSON serde derives.

pub fn generate_text(self, enabled: bool) -> Self

Toggle textproto support.

pub fn generate_arbitrary(self, enabled: bool) -> Self

Toggle arbitrary::Arbitrary derives.

pub fn preserve_unknown_fields(self, enabled: bool) -> Self

Toggle unknown-field preservation.

pub fn strict_utf8_mapping(self, enabled: bool) -> Self

Honor features.utf8_validation = NONE by mapping such strings to bytes — see buffa_build::Config::strict_utf8_mapping.

pub fn allow_message_set(self, enabled: bool) -> Self

Permit message_set_wire_format = true on input messages.

pub fn include_file(self, name: impl Into<String>) -> Self

Emit a per-package include-file alongside the per-proto outputs.

pub fn generate_view_reflection(self, enabled: bool) -> Self

Emit impl ReflectMessageView<'a> blocks for every generated view type into OUT_DIR/<view_reflection_include_file>. The downstream user include!s the file once after their buffa::include_proto!(...) invocation.

Default: true when the file_descriptor_set_bytes binding is configured (the only binding the emitter can plumb into a OnceLock initializer); false otherwise. Override explicitly to opt out.

pub fn view_reflection_include_file(self, name: impl Into<String>) -> Self

Override the file name of the view-reflection include file. Default: _reflect_views.rs.

pub fn view_reflection_root_path(self, path: impl Into<String>) -> Self

Override the Rust module path under which the generated view types live. Default: crate::__buffa::view, matching the buffa::include_proto! invocation at the crate root.

Override when the consumer wraps include_proto! inside a non-root module, e.g. pub mod my_pkg { buffa::include_proto!(...); } — set this to crate::my_pkg::__buffa::view.

pub fn compile(self) -> Result<(), Error>

Compile the configured .proto files.

Errors

See Error for the failure modes — most user errors are an unconfigured descriptor binding, a missing OUT_DIR, or protoc/buf invocation failure.

Trait Implementations

impl Debug for Builder

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

Formats the value using the given formatter.

impl Default for Builder

fn default() -> Builder

Returns the “default value” for a type.