use scythe_backend::manifest::BackendManifest;
use scythe_backend::naming::{enum_type_name, fn_name, row_struct_name, to_camel_case, to_pascal_case};
use scythe_backend::types::resolve_type;
use std::fmt::Write;
use scythe_core::analyzer::{AnalyzedQuery, CompositeInfo, EnumInfo};
use scythe_core::errors::{ErrorCode, ScytheError};
use scythe_core::parser::QueryCommand;
use crate::backend_trait::{CodegenBackend, GroupedQueryFn, ResolvedColumn, ResolvedParam};
use crate::backends::typescript_common::{
TsRowType, generate_grouped_interface_structs, generate_ts_grouped_fold_body, generate_zod_grouped_structs,
generate_zod_row_struct,
};
use crate::singularize;
const DEFAULT_MANIFEST_TOML: &str = include_str!("../../manifests/typescript-duckdb.toml");
pub struct TypescriptDuckdbBackend {
manifest: BackendManifest,
row_type: TsRowType,
}
impl TypescriptDuckdbBackend {
pub fn new(engine: &str) -> Result<Self, ScytheError> {
match engine {
"duckdb" => {}
_ => {
return Err(ScytheError::new(
ErrorCode::InternalError,
format!("typescript-duckdb only supports DuckDB, got engine '{}'", engine),
));
}
}
let manifest =
super::load_or_default_manifest("backends/typescript-duckdb/manifest.toml", DEFAULT_MANIFEST_TOML)?;
Ok(Self {
manifest,
row_type: TsRowType::default(),
})
}
}
impl CodegenBackend for TypescriptDuckdbBackend {
fn name(&self) -> &str {
"typescript-duckdb"
}
fn manifest(&self) -> &scythe_backend::manifest::BackendManifest {
&self.manifest
}
fn supported_engines(&self) -> &[&str] {
&["duckdb"]
}
fn file_header(&self) -> String {
let mut header =
"/** Auto-generated by scythe. Do not edit. */\n\nimport type { Connection } from \"@duckdb/node-api\";\n"
.to_string();
if self.row_type == TsRowType::Zod {
header.push_str("import { z } from \"zod\";\n");
}
header
}
fn generate_row_struct(&self, query_name: &str, columns: &[ResolvedColumn]) -> Result<String, ScytheError> {
let struct_name = row_struct_name(query_name, &self.manifest.naming);
if self.row_type == TsRowType::Zod {
return Ok(generate_zod_row_struct(&struct_name, query_name, columns));
}
let mut out = String::new();
let _ = writeln!(out, "/** Row type for {} queries. */", query_name);
let _ = writeln!(out, "export interface {} {{", struct_name);
for col in columns {
let _ = writeln!(out, "\t{}: {};", col.field_name, col.full_type);
}
let _ = write!(out, "}}");
Ok(out)
}
fn generate_model_struct(&self, table_name: &str, columns: &[ResolvedColumn]) -> Result<String, ScytheError> {
let singular = singularize(table_name);
let name = to_pascal_case(&singular);
self.generate_row_struct(&name, columns)
}
fn generate_query_fn(
&self,
analyzed: &AnalyzedQuery,
struct_name: &str,
_columns: &[ResolvedColumn],
params: &[ResolvedParam],
) -> Result<String, ScytheError> {
let func_name = fn_name(&analyzed.name, &self.manifest.naming);
let mut out = String::new();
let param_list = params
.iter()
.map(|p| format!("{}: {}", p.field_name, p.full_type))
.collect::<Vec<_>>()
.join(", ");
let sql = super::clean_sql_with_optional(&analyzed.sql, &analyzed.optional_params, &analyzed.params);
let inline_params = if params.is_empty() {
"conn: Connection".to_string()
} else {
format!("conn: Connection, {}", param_list)
};
let write_fn_sig = |out: &mut String, name: &str, params_inline: &str, ret: &str| {
let oneliner = format!("export async function {}({}): Promise<{}> {{", name, params_inline, ret);
if oneliner.len() <= 80 {
let _ = writeln!(out, "{}", oneliner);
} else {
let mut parts = vec!["\tconn: Connection".to_string()];
for p in params {
parts.push(format!("\t{}: {}", p.field_name, p.full_type));
}
let _ = writeln!(out, "export async function {}(", name);
for part in &parts {
let _ = writeln!(out, "{},", part);
}
let _ = writeln!(out, "): Promise<{}> {{", ret);
}
};
let write_prepare = |out: &mut String, sql: &str| {
let oneliner = format!("\tconst stmt = await conn.prepare(`{}`);", sql);
if oneliner.len() <= 80 {
let _ = writeln!(out, "{}", oneliner);
} else {
let _ = writeln!(out, "\tconst stmt = await conn.prepare(\n\t\t`{}`,\n\t);", sql);
}
};
let param_args = if params.is_empty() {
String::new()
} else {
let args: Vec<String> = params.iter().map(|p| p.field_name.clone()).collect();
args.join(", ")
};
match &analyzed.command {
QueryCommand::One | QueryCommand::Opt => {
let _ = writeln!(out, "/** Fetch a single {} or null. */", struct_name);
let ret = format!("{} | null", struct_name);
write_fn_sig(&mut out, &func_name, &inline_params, &ret);
write_prepare(&mut out, &sql);
if params.is_empty() {
let _ = writeln!(out, "\tconst result = await stmt.run();");
} else {
let _ = writeln!(out, "\tconst result = await stmt.run({});", param_args);
}
let _ = writeln!(out, "\tconst rows = await result.getRows();");
let _ = writeln!(
out,
"\tconst row = rows.length > 0 ? (rows[0] as unknown as {}) : null;",
struct_name
);
let _ = writeln!(out, "\treturn row;");
let _ = write!(out, "}}");
}
QueryCommand::Batch => {
let batch_fn_name = format!("{}Batch", func_name);
if params.len() > 1 {
let params_type_name = format!("{}BatchParams", struct_name);
let _ = writeln!(out, "/** Params for {} batch operation. */", struct_name);
let _ = writeln!(out, "export interface {} {{", params_type_name);
for p in params {
let _ = writeln!(out, "\t{}: {};", p.field_name, p.full_type);
}
let _ = writeln!(out, "}}");
let _ = writeln!(out);
let _ = writeln!(out, "/** Execute {} for each item in the batch. */", analyzed.name);
let batch_params = format!("conn: Connection, items: {}[]", params_type_name);
write_fn_sig(&mut out, &batch_fn_name, &batch_params, "void");
write_prepare(&mut out, &sql);
let _ = writeln!(out, "\tfor (const item of items) {{");
let args: Vec<String> = params.iter().map(|p| format!("item.{}", p.field_name)).collect();
let _ = writeln!(out, "\t\tawait stmt.run({});", args.join(", "));
let _ = writeln!(out, "\t}}");
let _ = write!(out, "}}");
} else if params.len() == 1 {
let _ = writeln!(out, "/** Execute {} for each item in the batch. */", analyzed.name);
let batch_params = format!("conn: Connection, items: {}[]", params[0].full_type);
write_fn_sig(&mut out, &batch_fn_name, &batch_params, "void");
write_prepare(&mut out, &sql);
let _ = writeln!(out, "\tfor (const item of items) {{");
let _ = writeln!(out, "\t\tawait stmt.run(item);");
let _ = writeln!(out, "\t}}");
let _ = write!(out, "}}");
} else {
let _ = writeln!(out, "/** Execute {} for each item in the batch. */", analyzed.name);
write_fn_sig(&mut out, &batch_fn_name, "conn: Connection, count: number", "void");
write_prepare(&mut out, &sql);
let _ = writeln!(out, "\tfor (let i = 0; i < count; i++) {{");
let _ = writeln!(out, "\t\tawait stmt.run();");
let _ = writeln!(out, "\t}}");
let _ = write!(out, "}}");
}
}
QueryCommand::Many => {
let _ = writeln!(out, "/** Fetch all {} rows. */", struct_name);
let ret = format!("{}[]", struct_name);
write_fn_sig(&mut out, &func_name, &inline_params, &ret);
write_prepare(&mut out, &sql);
if params.is_empty() {
let _ = writeln!(out, "\tconst result = await stmt.run();");
} else {
let _ = writeln!(out, "\tconst result = await stmt.run({});", param_args);
}
let _ = writeln!(
out,
"\treturn (await result.getRows()) as unknown as {}[];",
struct_name
);
let _ = write!(out, "}}");
}
QueryCommand::Exec => {
let _ = writeln!(out, "/** Execute a query returning no rows. */");
write_fn_sig(&mut out, &func_name, &inline_params, "void");
write_prepare(&mut out, &sql);
if params.is_empty() {
let _ = writeln!(out, "\tawait stmt.run();");
} else {
let _ = writeln!(out, "\tawait stmt.run({});", param_args);
}
let _ = write!(out, "}}");
}
QueryCommand::Grouped => {
unreachable!("Grouped command is routed through generate_grouped_query_fn, not generate_query_fn")
}
QueryCommand::ExecResult | QueryCommand::ExecRows => {
let _ = writeln!(out, "/** Execute a query and return the number of affected rows. */");
write_fn_sig(&mut out, &func_name, &inline_params, "number");
write_prepare(&mut out, &sql);
if params.is_empty() {
let _ = writeln!(out, "\tconst result = await stmt.run();");
} else {
let _ = writeln!(out, "\tconst result = await stmt.run({});", param_args);
}
let _ = writeln!(out, "\treturn result.rowsChanged;");
let _ = write!(out, "}}");
}
}
Ok(out)
}
fn generate_grouped_structs(
&self,
parent_struct_name: &str,
child_struct_name: &str,
parent_columns: &[ResolvedColumn],
child_columns: &[ResolvedColumn],
_key_column: &str,
) -> Result<String, ScytheError> {
if self.row_type == TsRowType::Zod {
return Ok(generate_zod_grouped_structs(
child_struct_name,
parent_struct_name,
parent_columns,
child_columns,
));
}
Ok(generate_grouped_interface_structs(
child_struct_name,
parent_struct_name,
parent_columns,
child_columns,
))
}
fn generate_grouped_query_fn(&self, request: &GroupedQueryFn<'_>) -> Result<String, ScytheError> {
let analyzed = request.analyzed;
let parent_struct_name = request.parent_struct_name;
let child_struct_name = request.child_struct_name;
let parent_columns = request.parent_columns;
let child_columns = request.child_columns;
let params = request.params;
let key_column = request.key_column;
let func_name = fn_name(&analyzed.name, &self.manifest.naming);
let sql = super::clean_sql_with_optional(&analyzed.sql, &analyzed.optional_params, &analyzed.params);
let param_list = params
.iter()
.map(|p| format!("{}: {}", p.field_name, p.full_type))
.collect::<Vec<_>>()
.join(", ");
let inline_params = if params.is_empty() {
"conn: Connection".to_string()
} else {
format!("conn: Connection, {}", param_list)
};
let ret = format!("Promise<{parent_struct_name}[]>");
let mut out = String::new();
let oneliner = format!("export async function {func_name}({inline_params}): {ret} {{");
if oneliner.len() <= 80 {
let _ = writeln!(out, "/** Fetch grouped {} rows. */", analyzed.name);
let _ = writeln!(out, "{oneliner}");
} else {
let _ = writeln!(out, "/** Fetch grouped {} rows. */", analyzed.name);
let _ = writeln!(out, "export async function {func_name}(");
let _ = writeln!(out, "\tconn: Connection,");
for p in params {
let _ = writeln!(out, "\t{}: {},", p.field_name, p.full_type);
}
let _ = writeln!(out, "): {ret} {{");
}
let _ = writeln!(out, "\tconst stmt = await conn.prepare(`{sql}`);");
if params.is_empty() {
let _ = writeln!(out, "\tconst _result = await stmt.run();");
} else {
let args: Vec<String> = params.iter().map(|p| p.field_name.clone()).collect();
let _ = writeln!(out, "\tconst _result = await stmt.run({});", args.join(", "));
}
let _ = writeln!(
out,
"\tconst flatRows = await _result.getRows() as unknown as Record<string, unknown>[];"
);
let fold = generate_ts_grouped_fold_body(
parent_struct_name,
child_struct_name,
parent_columns,
child_columns,
key_column,
|name, ty| format!("row['{name}'] as {ty}"),
);
out.push_str(&fold);
let _ = write!(out, "}}");
Ok(out)
}
fn generate_enum_def(&self, enum_info: &EnumInfo) -> Result<String, ScytheError> {
let type_name = enum_type_name(&enum_info.sql_name, &self.manifest.naming);
if self.row_type == TsRowType::Zod {
return Ok(super::typescript_common::generate_zod_enum(
&type_name,
&enum_info.values,
));
}
let mut out = String::new();
let variants: Vec<String> = enum_info.values.iter().map(|v| format!("\"{}\"", v)).collect();
let _ = write!(out, "export type {} = {};", type_name, variants.join(" | "));
Ok(out)
}
fn generate_composite_def(&self, composite: &CompositeInfo) -> Result<String, ScytheError> {
let name = to_pascal_case(&composite.sql_name);
let mut out = String::new();
let _ = writeln!(out, "/** Composite type {}. */", composite.sql_name);
let _ = writeln!(out, "export interface {} {{", name);
for field in &composite.fields {
let ts_type = resolve_type(&field.neutral_type, &self.manifest, false)
.map(|t| t.into_owned())
.map_err(|e| {
ScytheError::new(ErrorCode::InternalError, format!("composite field type error: {}", e))
})?;
let _ = writeln!(out, "\t{}: {};", to_camel_case(&field.name), ts_type);
}
let _ = write!(out, "}}");
Ok(out)
}
fn apply_options(&mut self, options: &std::collections::HashMap<String, String>) -> Result<(), ScytheError> {
if let Some(value) = options.get("row_type") {
self.row_type = TsRowType::from_option(value)?;
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::TypescriptDuckdbBackend;
use scythe_core::analyzer::{AnalyzedColumn, AnalyzedQuery, GroupByConfig};
use scythe_core::parser::QueryCommand;
fn make_grouped_query() -> AnalyzedQuery {
let parent_cols = vec![
AnalyzedColumn {
name: "id".to_string(),
neutral_type: "int32".to_string(),
nullable: false,
},
AnalyzedColumn {
name: "name".to_string(),
neutral_type: "string".to_string(),
nullable: false,
},
];
let child_cols = vec![
AnalyzedColumn {
name: "order_id".to_string(),
neutral_type: "int32".to_string(),
nullable: false,
},
AnalyzedColumn {
name: "total".to_string(),
neutral_type: "decimal".to_string(),
nullable: true,
},
];
let all_cols = [parent_cols.clone(), child_cols.clone()].concat();
AnalyzedQuery {
name: "GetUsersWithOrders".to_string(),
command: QueryCommand::Grouped,
sql: "SELECT u.id, u.name, o.id AS order_id, o.total FROM users u JOIN orders o ON o.user_id = u.id"
.to_string(),
columns: all_cols,
params: vec![],
deprecated: None,
source_table: None,
composites: vec![],
enums: vec![],
optional_params: vec![],
group_by: Some(GroupByConfig {
table: "users".to_string(),
key_column: "id".to_string(),
parent_columns: parent_cols,
child_columns: child_cols,
}),
custom: vec![],
}
}
#[test]
fn test_grouped_typescript_duckdb_structs() {
let backend = TypescriptDuckdbBackend::new("duckdb").unwrap();
let query = make_grouped_query();
let result = crate::generate_with_backend(&query, &backend).unwrap();
let row_struct = result.row_struct.as_deref().unwrap();
assert!(
row_struct.contains("interface GetUsersWithOrdersChildRow"),
"missing child; got:\n{row_struct}"
);
assert!(
row_struct.contains("interface GetUsersWithOrdersRow"),
"missing parent; got:\n{row_struct}"
);
assert!(
row_struct.contains("children: GetUsersWithOrdersChildRow[]"),
"missing children; got:\n{row_struct}"
);
let child_pos = row_struct.find("GetUsersWithOrdersChildRow").unwrap();
let parent_pos = row_struct.find("interface GetUsersWithOrdersRow").unwrap();
assert!(child_pos < parent_pos, "child must precede parent");
}
#[test]
fn test_grouped_typescript_duckdb_query_fn() {
let backend = TypescriptDuckdbBackend::new("duckdb").unwrap();
let query = make_grouped_query();
let result = crate::generate_with_backend(&query, &backend).unwrap();
let query_fn = result.query_fn.as_deref().unwrap();
assert!(query_fn.contains("getUsersWithOrders"), "missing fn; got:\n{query_fn}");
assert!(
query_fn.contains("Promise<GetUsersWithOrdersRow[]>"),
"wrong return type; got:\n{query_fn}"
);
assert!(
query_fn.contains("conn.prepare"),
"must use conn.prepare; got:\n{query_fn}"
);
assert!(query_fn.contains("getRows()"), "must call getRows; got:\n{query_fn}");
assert!(
query_fn.contains("new Map<unknown, GetUsersWithOrdersRow>()"),
"must use Map; got:\n{query_fn}"
);
assert!(
query_fn.contains("parent.children.push"),
"must fold children; got:\n{query_fn}"
);
}
}