use scythe_backend::manifest::BackendManifest;
use scythe_backend::naming::{
enum_type_name, enum_variant_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::GroupedQueryFn;
use crate::backend_trait::{CodegenBackend, ResolvedColumn, ResolvedParam};
use crate::backends::typescript_common::{
TsRowType, generate_grouped_interface_structs, generate_ts_grouped_fold_body, generate_zod_enum,
generate_zod_grouped_structs, generate_zod_row_struct,
};
use crate::singularize;
const DEFAULT_MANIFEST_TOML: &str = include_str!("../../manifests/typescript-postgres.toml");
const DEFAULT_MANIFEST_REDSHIFT: &str = include_str!("../../manifests/typescript-postgres.redshift.toml");
pub struct TypescriptPostgresBackend {
manifest: BackendManifest,
row_type: TsRowType,
}
impl TypescriptPostgresBackend {
pub fn new(engine: &str) -> Result<Self, ScytheError> {
let default_toml = match engine {
"postgresql" | "postgres" | "pg" => DEFAULT_MANIFEST_TOML,
"redshift" => DEFAULT_MANIFEST_REDSHIFT,
_ => {
return Err(ScytheError::new(
ErrorCode::InternalError,
format!(
"typescript-postgres only supports PostgreSQL/Redshift, got engine '{}'",
engine
),
));
}
};
let manifest = super::load_or_default_manifest("backends/typescript-postgres/manifest.toml", default_toml)?;
Ok(Self {
manifest,
row_type: TsRowType::default(),
})
}
}
impl CodegenBackend for TypescriptPostgresBackend {
fn name(&self) -> &str {
"typescript-postgres"
}
fn manifest(&self) -> &scythe_backend::manifest::BackendManifest {
&self.manifest
}
fn supported_engines(&self) -> &[&str] {
&["postgresql", "redshift"]
}
fn file_header(&self) -> String {
let mut header =
"/** Auto-generated by scythe. Do not edit. */\n\nimport type { Sql } from \"postgres\";\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 _sep = if param_list.is_empty() { "" } else { ", " };
let sql_clean = super::clean_sql_with_optional(&analyzed.sql, &analyzed.optional_params, &analyzed.params);
let name_map: std::collections::HashMap<u32, String> = analyzed
.params
.iter()
.zip(params.iter())
.map(|(ap, rp)| (ap.position as u32, rp.field_name.clone()))
.collect();
let sql_template = super::rewrite_pg_placeholders(&sql_clean, |n| {
format!("${{{}}}", name_map.get(&n).map_or("?", |s| s.as_str()))
});
let inline_params = if params.is_empty() {
"sql: Sql".to_string()
} else {
format!("sql: Sql, {}", param_list)
};
let write_fn_sig = |out: &mut String, name: &str, params_inline: &str, ret: &str| {
let oneliner = format!("export async function {}({}): {} {{", name, params_inline, ret);
if oneliner.len() <= 80 {
let _ = writeln!(out, "{}", oneliner);
} else {
let mut parts = vec!["\tsql: Sql".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, "): {} {{", ret);
}
};
match &analyzed.command {
QueryCommand::One | QueryCommand::Opt => {
let _ = writeln!(out, "/** Fetch a single {} or null. */", struct_name);
let ret = format!("Promise<{} | null>", struct_name);
write_fn_sig(&mut out, &func_name, &inline_params, &ret);
let _ = writeln!(out, "\tconst rows = await sql<{}[]>`", struct_name);
let _ = writeln!(out, " {}", sql_template);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\treturn rows[0] ?? null;");
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 within a transaction. */",
analyzed.name
);
let batch_params = format!("sql: Sql, items: {}[]", params_type_name);
write_fn_sig(&mut out, &batch_fn_name, &batch_params, "Promise<void>");
let _ = writeln!(out, "\tawait sql.begin(async (tx) => {{");
let _ = writeln!(out, "\t\tfor (const item of items) {{");
let batch_sql = {
let mut s = sql_clean.clone();
let mut indexed: Vec<(i64, &str)> = analyzed
.params
.iter()
.zip(params.iter())
.map(|(ap, rp)| (ap.position, rp.field_name.as_str()))
.collect();
indexed.sort_by_key(|b| std::cmp::Reverse(b.0));
for (pos, field_name) in indexed {
let placeholder = format!("${}", pos);
let replacement = format!("${{item.{}}}", field_name);
s = s.replace(&placeholder, &replacement);
}
s
};
let _ = writeln!(out, "\t\t\tawait tx`");
let _ = writeln!(out, " {}", batch_sql);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\t\t}}");
let _ = writeln!(out, "\t}});");
let _ = write!(out, "}}");
} else if params.len() == 1 {
let _ = writeln!(
out,
"/** Execute {} for each item in the batch within a transaction. */",
analyzed.name
);
let batch_params = format!("sql: Sql, items: {}[]", params[0].full_type);
write_fn_sig(&mut out, &batch_fn_name, &batch_params, "Promise<void>");
let _ = writeln!(out, "\tawait sql.begin(async (tx) => {{");
let _ = writeln!(out, "\t\tfor (const item of items) {{");
let batch_sql = sql_template.replace(&format!("${{{}}}", params[0].field_name), "${item}");
let _ = writeln!(out, "\t\t\tawait tx`");
let _ = writeln!(out, " {}", batch_sql);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\t\t}}");
let _ = writeln!(out, "\t}});");
let _ = write!(out, "}}");
} else {
let _ = writeln!(
out,
"/** Execute {} for each item in the batch within a transaction. */",
analyzed.name
);
write_fn_sig(&mut out, &batch_fn_name, "sql: Sql, count: number", "Promise<void>");
let _ = writeln!(out, "\tawait sql.begin(async (tx) => {{");
let _ = writeln!(out, "\t\tfor (let i = 0; i < count; i++) {{");
let _ = writeln!(out, "\t\t\tawait tx`");
let _ = writeln!(out, " {}", sql_template);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\t\t}}");
let _ = writeln!(out, "\t}});");
let _ = write!(out, "}}");
}
}
QueryCommand::Many => {
let _ = writeln!(out, "/** Fetch all {} rows. */", struct_name);
let ret = format!("Promise<{}[]>", struct_name);
write_fn_sig(&mut out, &func_name, &inline_params, &ret);
let _ = writeln!(out, "\tconst rows = await sql<{}[]>`", struct_name);
let _ = writeln!(out, " {}", sql_template);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\treturn rows;");
let _ = write!(out, "}}");
}
QueryCommand::Exec => {
let _ = writeln!(out, "/** Execute a query returning no rows. */");
write_fn_sig(&mut out, &func_name, &inline_params, "Promise<void>");
let _ = writeln!(out, "\tawait sql`");
let _ = writeln!(out, " {}", sql_template);
let _ = writeln!(out, " `;");
let _ = write!(out, "}}");
}
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, "Promise<number>");
let _ = writeln!(out, "\tconst result = await sql`");
let _ = writeln!(out, " {}", sql_template);
let _ = writeln!(out, " `;");
let _ = writeln!(out, "\treturn result.count;");
let _ = write!(out, "}}");
}
QueryCommand::Grouped => {
unreachable!("Grouped command is routed through generate_grouped_query_fn, not generate_query_fn")
}
}
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_clean = super::clean_sql_with_optional(&analyzed.sql, &analyzed.optional_params, &analyzed.params);
let name_map: std::collections::HashMap<u32, String> = analyzed
.params
.iter()
.zip(params.iter())
.map(|(ap, rp)| (ap.position as u32, rp.field_name.clone()))
.collect();
let sql_template = super::rewrite_pg_placeholders(&sql_clean, |n| {
format!("${{{}}}", name_map.get(&n).map_or("?", |s| s.as_str()))
});
let param_list = params
.iter()
.map(|p| format!("{}: {}", p.field_name, p.full_type))
.collect::<Vec<_>>()
.join(", ");
let inline_params = if params.is_empty() {
"sql: Sql".to_string()
} else {
format!("sql: Sql, {}", 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, "\tsql: Sql,");
for p in params {
let _ = writeln!(out, "\t{}: {},", p.field_name, p.full_type);
}
let _ = writeln!(out, "): {ret} {{");
}
let _ = writeln!(out, "\tconst flatRows = await sql<Record<string, unknown>[]>`");
let _ = writeln!(out, " {sql_template}");
let _ = writeln!(out, " `;");
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(generate_zod_enum(&type_name, &enum_info.values));
}
let mut out = String::new();
let _ = writeln!(out, "export enum {} {{", type_name);
for value in &enum_info.values {
let variant = enum_variant_name(value, &self.manifest.naming);
let _ = writeln!(out, "\t{} = \"{}\",", variant, value);
}
let _ = write!(out, "}}");
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);
if composite.fields.is_empty() {
} else {
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::TypescriptPostgresBackend;
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,
},
AnalyzedColumn {
name: "email".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,
},
AnalyzedColumn {
name: "order_date".to_string(),
neutral_type: "datetime".to_string(),
nullable: false,
},
];
let all_cols = [parent_cols.clone(), child_cols.clone()].concat();
AnalyzedQuery {
name: "GetUsersWithOrders".to_string(),
command: QueryCommand::Grouped,
sql: "SELECT u.id, u.name, u.email, o.id AS order_id, o.total, o.created_at AS order_date\nFROM users u\nJOIN 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_postgres_structs() {
let backend = TypescriptPostgresBackend::new("postgresql").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("order_id: number"),
"child missing order_id; 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_postgres_query_fn() {
let backend = TypescriptPostgresBackend::new("postgresql").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("sql<Record<string, unknown>[]>"),
"must use typed sql template; 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}"
);
assert!(
query_fn.contains("return result"),
"must return result; got:\n{query_fn}"
);
}
}