Trait CodegenBackend 

pub trait CodegenBackend: Send + Sync {
    // Required methods
    fn name(&self) -> &str;
    fn manifest(&self) -> &BackendManifest;
    fn generate_row_struct(
        &self,
        query_name: &str,
        columns: &[ResolvedColumn],
    ) -> Result<String, ScytheError>;
    fn generate_model_struct(
        &self,
        table_name: &str,
        columns: &[ResolvedColumn],
    ) -> Result<String, ScytheError>;
    fn generate_query_fn(
        &self,
        analyzed: &AnalyzedQuery,
        struct_name: &str,
        columns: &[ResolvedColumn],
        params: &[ResolvedParam],
    ) -> Result<String, ScytheError>;
    fn generate_enum_def(
        &self,
        enum_info: &EnumInfo,
    ) -> Result<String, ScytheError>;
    fn generate_composite_def(
        &self,
        composite: &CompositeInfo,
    ) -> Result<String, ScytheError>;

    // Provided methods
    fn file_header(&self) -> String { ... }
    fn file_footer(&self) -> String { ... }
    fn query_class_header(&self) -> String { ... }
    fn generate_rbs_file(
        &self,
        _context: &RbsGenerationContext,
    ) -> Option<String> { ... }
    fn apply_options(
        &mut self,
        _options: &HashMap<String, String>,
    ) -> Result<(), ScytheError> { ... }
    fn supported_engines(&self) -> &[&str] { ... }
}

Trait that all codegen backends must implement.

Required Methods

fn name(&self) -> &str

The backend’s name (e.g. “rust-sqlx”, “rust-tokio-postgres”).

fn manifest(&self) -> &BackendManifest

The backend’s manifest (type mappings, naming conventions, etc).

fn generate_row_struct( &self, query_name: &str, columns: &[ResolvedColumn], ) -> Result<String, ScytheError>

Generate a row struct for a query result.

fn generate_model_struct( &self, table_name: &str, columns: &[ResolvedColumn], ) -> Result<String, ScytheError>

Generate a model struct for a table.

fn generate_query_fn( &self, analyzed: &AnalyzedQuery, struct_name: &str, columns: &[ResolvedColumn], params: &[ResolvedParam], ) -> Result<String, ScytheError>

Generate a query function.

fn generate_enum_def(&self, enum_info: &EnumInfo) -> Result<String, ScytheError>

Generate an enum definition.

fn generate_composite_def( &self, composite: &CompositeInfo, ) -> Result<String, ScytheError>

Generate a composite type definition.

Provided Methods

fn file_header(&self) -> String

Generate a file-level header (imports, docstring, etc). Returns an empty string by default; backends may override.

fn file_footer(&self) -> String

Generate a file-level footer (closing braces, etc). Returns an empty string by default; backends may override.

fn query_class_header(&self) -> String

Generate a class header that wraps query functions only. When non-empty, the assembly will emit all type definitions (enums, row structs, model structs) first, then this class header, then all query functions, then the file footer. Returns an empty string by default (no class wrapper).

fn generate_rbs_file(&self, _context: &RbsGenerationContext) -> Option<String>

Generate an RBS type signature file for Ruby backends. Returns None by default; Ruby backends override this.

fn apply_options( &mut self, _options: &HashMap<String, String>, ) -> Result<(), ScytheError>

Apply per-backend configuration options from [[sql.gen]]. Backends override this to handle options like row_type = "pydantic".

fn supported_engines(&self) -> &[&str]

Database engines this backend supports. Defaults to PostgreSQL only. Multi-DB backends override this.

Implementors