Navigating the code

The code for UniFFI is organized into the following crates:

• ./uniffi (docs.rs, source): The main entry-point to UniFFI - almost all consumers should be able to use facilities expored by this module.

• ./uniffi_bindgen (docs.rs, source): The the source for the uniffi-bindgen executable and is where most of the logic for the foreign bindings generation lives. Its contents include:

  • ./uniffi_bindgen/src/interface/: Converting uniffi_meta types into an in-memory representation called ComponentInterface, from which we can generate code for different languages.
  • ./uniffi_bindgen/src/scaffolding: This module generates .rs files for the parts of the ComponentInterface defined in UDL
  • ./uniffi_bindgen/src/bindings/: This module turns a ComponentInterface into foreign-language bindings, the code that can load the FFI layer exposed by Rust and expose it as a higher-level API in a target language. There is a sub-module for each internally supported language.

• ./uniffi_meta(docs.rs, source): The types used to represent the metadata used to describe the ComponentInterface used to generate the Rust scaffolding and the foreign bindings.

• ./uniffi_udl(docs.rs, source) : The parsing of UDL files, turning them into uniffi_meta types.

• ./uniffi_build(docs.rs, source): A small hook to run uniffi-bindgen from the build.rs script of a UniFFI component, in order to automatically generate the Rust scaffolding as part of its build process.

• ./uniffi_macros(docs.rs, source): Contains the proc_macro support, which does much of the heavy-lifting for defining the Rust FFI.

• ./examples: Contains code examples demonstrating the capabilites and code generation process.

• ./fixtures: Our test suite.