#![expect(
clippy::min_ident_chars,
reason = "Short closure bindings keep nested metadata traversals and quoted Rust readable."
)]
use alloc::collections::{BTreeMap, BTreeSet};
use heck::{ToSnakeCase as _, ToUpperCamelCase as _};
use proc_macro2::{Ident, Span, TokenStream};
use quote::quote;
use syn::parse::Parser as _;
use crate::{Config, Error, model::*};
fn invalid(message: impl Into<String>) -> Error {
Error::Invalid(message.into())
}
fn ident(name: &str, camel: bool) -> Result<Ident, Error> {
let mut normalized = if camel {
name.to_upper_camel_case()
} else {
name.to_snake_case()
};
if normalized.is_empty() {
return Err(invalid(format!(
"identifier {name:?} has no Rust identifier characters"
)));
}
if normalized.starts_with(|c: char| c.is_ascii_digit()) {
normalized.insert(0, '_');
}
if matches!(normalized.as_str(), "self" | "Self" | "super" | "crate") {
normalized.push('_');
}
syn::parse_str::<Ident>(&normalized)
.or_else(|_| syn::parse_str::<Ident>(&format!("r#{normalized}")))
.map_err(|_error| {
invalid(format!(
"cannot convert PostgreSQL identifier {name:?} to Rust"
))
})
}
fn unique<'a>(
names: impl IntoIterator<Item = &'a str>,
camel: bool,
context: &str,
) -> Result<(), Error> {
let mut seen = BTreeMap::new();
for name in names {
let rust = ident(name, camel)?.to_string();
if let Some(previous) = seen.insert(rust.clone(), name) {
return Err(invalid(format!(
"{context}: identifiers {previous:?} and {name:?} collide as {rust}"
)));
}
}
Ok(())
}
fn identifiers(tokens: TokenStream, names: &mut BTreeSet<String>) {
for token in tokens {
match token {
proc_macro2::TokenTree::Ident(name) => {
names.insert(name.to_string());
}
proc_macro2::TokenTree::Group(group) => identifiers(group.stream(), names),
proc_macro2::TokenTree::Punct(_) | proc_macro2::TokenTree::Literal(_) => {}
}
}
}
fn override_aliases(
prelude: &syn::File,
types: BTreeMap<String, syn::Type>,
) -> (TokenStream, BTreeMap<String, Ident>) {
let mut occupied = BTreeSet::new();
identifiers(quote!(#prelude), &mut occupied);
for ty in types.values() {
identifiers(quote!(#ty), &mut occupied);
}
let mut aliases = TokenStream::new();
let mut overrides = BTreeMap::new();
let mut serial = 0_usize;
for (key, ty) in types {
let name = loop {
let name = format!("__SupabaseCodegenType{serial}");
serial = serial.saturating_add(1_usize);
if occupied.insert(name.clone()) {
break Ident::new(&name, Span::call_site());
}
};
aliases.extend(quote!(type #name = #ty;));
overrides.insert(key, name);
}
(aliases, overrides)
}
struct Emitter<'a> {
config: &'a Config,
runtime: syn::Path,
derives: Vec<syn::Path>,
attributes: Vec<syn::Attribute>,
targeted: BTreeMap<String, Vec<syn::Attribute>>,
used_targets: BTreeSet<String>,
overrides: BTreeMap<String, Ident>,
named: BTreeMap<(String, String), bool>, }
fn attributes(values: &[String]) -> Result<Vec<syn::Attribute>, Error> {
let mut result = Vec::new();
for value in values {
let parsed = syn::Attribute::parse_outer
.parse_str(value)
.map_err(|e| invalid(format!("invalid type attribute {value:?}: {e}")))?;
if parsed.is_empty() {
return Err(invalid("type attribute cannot be empty"));
}
result.extend(parsed);
}
Ok(result)
}
impl Emitter<'_> {
fn decoration(&mut self, target: &str, deserialize: bool, default: bool) -> TokenStream {
self.used_targets.insert(target.to_owned());
let attrs = &self.attributes;
let targeted = self.targeted.get(target).cloned().unwrap_or_default();
let mut derives: Vec<syn::Path> = vec![
syn::parse_quote!(::serde::Serialize),
syn::parse_quote!(Debug),
syn::parse_quote!(Clone),
];
if deserialize {
derives.push(syn::parse_quote!(::serde::Deserialize));
}
if default {
derives.push(syn::parse_quote!(Default));
}
for derive in &self.derives {
if !derives
.iter()
.any(|p| quote!(#p).to_string() == quote!(#derive).to_string())
{
derives.push(derive.clone());
}
}
quote!(#(#attrs)* #(#targeted)* #[derive(#(#derives),*)])
}
#[expect(
clippy::too_many_lines,
reason = "One SQL wire-type mapping keeps scalar choices visible together."
)]
fn ty(&self, ty: &PgType, depth: usize) -> Result<TokenStream, Error> {
let key = match ty {
PgType::Builtin(name) => Some(if name.contains('.') {
name.clone()
} else {
format!("pg_catalog.{name}")
}),
PgType::Named { schema, name } | PgType::Domain { schema, name, .. } => {
Some(format!("{schema}.{name}"))
}
PgType::Array(_) => None,
};
if let Some(overridden) = key.as_ref().and_then(|key| self.overrides.get(key)) {
let parents = core::iter::repeat_with(|| quote!(super::)).take(depth);
return Ok(quote!(#(#parents)* #overridden));
}
match ty {
PgType::Domain { base, .. } => self.ty(base, depth),
PgType::Array(inner) => {
let inner = self.ty(inner, depth)?;
let runtime = &self.runtime;
Ok(quote!(#runtime::Array<#inner>))
}
PgType::Named { schema, name } => {
let composite = self.named.get(&(schema.clone(), name.clone())).ok_or_else(|| invalid(format!("unresolved PostgreSQL type {schema}.{name}; include its schema metadata or supply type_override")))?;
let schema = ident(schema, false)?;
let name = ident(name, true)?;
let scope = if *composite {
quote!(composites)
} else {
quote!(enums)
};
let parents = core::iter::repeat_with(|| quote!(super::)).take(depth);
Ok(quote!(#(#parents)* #schema::#scope::#name))
}
PgType::Builtin(name) => {
let name = name.strip_prefix("pg_catalog.").unwrap_or(name);
Ok(match name {
"bool" | "boolean" => quote!(::core::primitive::bool),
"int2" | "smallint" => quote!(::core::primitive::i16),
"int4" | "integer" => quote!(::core::primitive::i32),
"int8" | "bigint" => quote!(::core::primitive::i64),
"oid" | "xid" | "cid" => quote!(::core::primitive::u32),
"float4" | "real" => quote!(::core::primitive::f32),
"float8" | "double precision" => quote!(::core::primitive::f64),
"numeric" | "decimal" => quote!(::serde_json::Number),
"json" | "jsonb" => quote!(::serde_json::Value),
"uuid" => quote!(::uuid::Uuid),
"date" => quote!(::chrono::NaiveDate),
"time" | "time without time zone" => quote!(::chrono::NaiveTime),
"timestamp" | "timestamp without time zone" => quote!(::chrono::NaiveDateTime),
"timestamptz" | "timestamp with time zone" => {
quote!(::chrono::DateTime<::chrono::FixedOffset>)
}
"void" => quote!(()),
"text"
| "varchar"
| "character varying"
| "bpchar"
| "character"
| "char"
| "name"
| "bytea"
| "inet"
| "cidr"
| "macaddr"
| "macaddr8"
| "interval"
| "timetz"
| "time with time zone"
| "point"
| "line"
| "lseg"
| "box"
| "path"
| "polygon"
| "circle"
| "int4range"
| "int8range"
| "numrange"
| "tsrange"
| "tstzrange"
| "daterange"
| "int4multirange"
| "int8multirange"
| "nummultirange"
| "tsmultirange"
| "tstzmultirange"
| "datemultirange"
| "tsvector"
| "tsquery"
| "bit"
| "varbit"
| "xml"
| "pg_lsn"
| "money" => quote!(::std::string::String),
_ => {
return Err(invalid(format!(
"unsupported PostgreSQL type pg_catalog.{name}; supply an explicit type_override"
)));
}
})
}
}
}
fn fields(
&self,
columns: &[Column],
depth: usize,
mode: &str,
context: &str,
) -> Result<TokenStream, Error> {
unique(columns.iter().map(|c| c.name.as_str()), false, context)?;
let mut fields = TokenStream::new();
for column in columns {
if matches!(mode, "insert" | "update")
&& (column.generated || column.identity == Identity::Always)
{
continue;
}
let name = ident(&column.name, false)?;
let wire = &column.name;
let base = self.ty(&column.ty, depth)?;
let nullable = column.nullable || matches!(mode, "composite" | "view" | "record");
let ty = if nullable {
quote!(::std::option::Option<#base>)
} else {
base
};
let optional = mode == "update"
|| mode == "insert"
&& (nullable || column.has_default || column.identity == Identity::ByDefault);
if optional {
let runtime = &self.runtime;
let skip = format!(
"{}::Field::is_omit",
quote!(#runtime).to_string().replace(' ', "")
);
fields.extend(quote!(#[serde(rename = #wire, skip_serializing_if = #skip)] pub #name: #runtime::Field<#ty>,));
} else {
fields.extend(quote!(#[serde(rename = #wire)] pub #name: #ty,));
}
}
Ok(fields)
}
fn is_record(&self, ty: &PgType) -> bool {
match ty {
PgType::Named { schema, name } => self
.named
.get(&(schema.clone(), name.clone()))
.copied()
.unwrap_or(false),
PgType::Domain { base, .. } => self.is_record(base),
PgType::Builtin(_) | PgType::Array(_) => false,
}
}
fn function_returns(
&mut self,
function: &Function,
target: &str,
) -> Result<(TokenStream, TokenStream), Error> {
let mut record = TokenStream::new();
let returns = match &function.returns {
ReturnType::Record(columns) => {
let decoration = self.decoration(&format!("{target}.Record"), true, false);
let fields = self.fields(columns, 3, "record", target)?;
record.extend(quote!(#decoration pub struct Record { #fields }));
if function.returns_set {
quote!(::std::vec::Vec<Record>)
} else {
quote!(Record)
}
}
ReturnType::Type(ty) => {
let base = self.ty(ty, 3)?;
if matches!(ty, PgType::Builtin(name) if name == "void" || name == "pg_catalog.void")
{
quote!(())
} else if self.is_record(ty) {
if function.returns_set {
quote!(::std::vec::Vec<#base>)
} else {
base
}
} else if function.returns_set {
quote!(::std::vec::Vec<::std::option::Option<#base>>)
} else {
quote!(::std::option::Option<#base>)
}
}
};
Ok((record, returns))
}
}
fn references(ty: &PgType, config: &Config, output: &mut BTreeSet<String>) {
match ty {
PgType::Named { schema, name } => {
if !config
.type_overrides
.contains_key(&format!("{schema}.{name}"))
{
output.insert(schema.clone());
}
}
PgType::Domain { schema, name, base } => {
if !config
.type_overrides
.contains_key(&format!("{schema}.{name}"))
{
references(base, config, output);
}
}
PgType::Array(base) => references(base, config, output),
PgType::Builtin(_) => {}
}
}
#[expect(
clippy::too_many_lines,
reason = "One schema traversal keeps emitted nesting and relative type paths together."
)]
pub fn generate(snapshot: &Snapshot, config: &Config) -> Result<String, Error> {
if snapshot.version != SNAPSHOT_VERSION {
return Err(invalid(format!(
"unsupported snapshot version {}",
snapshot.version
)));
}
let runtime = syn::parse_str::<syn::Path>(&config.runtime_path)
.map_err(|e| invalid(format!("invalid runtime path: {e}")))?;
let prelude =
syn::parse_file(&config.prelude).map_err(|e| invalid(format!("invalid prelude: {e}")))?;
let derives = config
.derives
.iter()
.map(|d| {
syn::parse_str::<syn::Path>(d)
.map_err(|e| invalid(format!("invalid derive {d:?}: {e}")))
})
.collect::<Result<_, _>>()?;
let override_types: BTreeMap<String, syn::Type> = config
.type_overrides
.iter()
.map(|(key, value)| {
Ok((
key.clone(),
syn::parse_str::<syn::Type>(value)
.map_err(|e| invalid(format!("invalid override for {key}: {e}")))?,
))
})
.collect::<Result<_, Error>>()?;
let (aliases, overrides) = override_aliases(&prelude, override_types);
let targeted = config
.type_attributes
.iter()
.map(|(key, value)| Ok((key.clone(), attributes(value)?)))
.collect::<Result<_, Error>>()?;
unique(
snapshot.schemas.iter().map(|s| s.name.as_str()),
false,
"schemas",
)?;
let schemas: BTreeMap<_, _> = snapshot
.schemas
.iter()
.map(|s| (s.name.clone(), s))
.collect();
let mut included: BTreeSet<_> = config.schemas.iter().cloned().collect();
if included.is_empty() {
return Err(invalid("at least one schema must be selected"));
}
loop {
let before = included.len();
for name in included.clone() {
let schema = schemas
.get(&name)
.ok_or_else(|| invalid(format!("schema {name:?} is absent from snapshot")))?;
for ty in schema
.tables
.iter()
.flat_map(|t| t.columns.iter().map(|c| &c.ty))
.chain(
schema
.composites
.iter()
.flat_map(|c| c.fields.iter().map(|c| &c.ty)),
)
.chain(
schema
.functions
.iter()
.flat_map(|f| f.arguments.iter().map(|a| &a.ty)),
)
{
references(ty, config, &mut included);
}
for function in &schema.functions {
match &function.returns {
ReturnType::Type(ty) => references(ty, config, &mut included),
ReturnType::Record(fields) => {
for field in fields {
references(&field.ty, config, &mut included);
}
}
}
}
}
if included.len() == before {
break;
}
}
let mut emitter = Emitter {
config,
runtime,
derives,
attributes: attributes(&config.attributes)?,
targeted,
used_targets: BTreeSet::new(),
overrides,
named: BTreeMap::new(),
};
for name in &included {
let schema = schemas
.get(name)
.ok_or_else(|| invalid(format!("schema {name:?} is absent from snapshot")))?;
unique(
schema.enums.iter().map(|e| e.name.as_str()),
true,
&format!("{name}.enums"),
)?;
unique(
schema.composites.iter().map(|e| e.name.as_str()),
true,
&format!("{name}.composites"),
)?;
for (type_name, composite) in schema
.enums
.iter()
.map(|e| (&e.name, false))
.chain(schema.composites.iter().map(|c| (&c.name, true)))
{
if emitter
.named
.insert((name.clone(), type_name.clone()), composite)
.is_some()
{
return Err(invalid(format!("duplicate named type {name}.{type_name}")));
}
}
}
let mut modules = TokenStream::new();
for schema_name in included {
let schema = schemas
.get(&schema_name)
.ok_or_else(|| invalid(format!("schema {schema_name:?} is absent from snapshot")))?;
let schema_ident = ident(&schema_name, false)?;
let mut enums = TokenStream::new();
let mut sorted: Vec<_> = schema.enums.iter().collect();
sorted.sort_by_key(|e| &e.name);
for enumeration in sorted {
unique(
enumeration.variants.iter().map(String::as_str),
true,
&format!("enum {schema_name}.{}", enumeration.name),
)?;
let name = ident(&enumeration.name, true)?;
let target = format!("{schema_ident}.enums.{name}");
let decoration = emitter.decoration(&target, true, false);
let mut variants = TokenStream::new();
for label in &enumeration.variants {
let variant = ident(label, true)?;
variants.extend(quote!(#[serde(rename = #label)] #variant,));
}
enums.extend(quote!(#decoration pub enum #name { #variants }));
}
let mut composites = TokenStream::new();
let mut sorted: Vec<_> = schema.composites.iter().collect();
sorted.sort_by_key(|c| &c.name);
for composite in sorted {
let name = ident(&composite.name, true)?;
let target = format!("{schema_ident}.composites.{name}");
let decoration = emitter.decoration(&target, true, false);
let fields = emitter.fields(&composite.fields, 2, "composite", &target)?;
composites.extend(quote!(#decoration pub struct #name { #fields }));
}
unique(
schema.tables.iter().map(|t| t.name.as_str()),
false,
&format!("{schema_name}.tables"),
)?;
let mut tables = TokenStream::new();
let mut sorted: Vec<_> = schema.tables.iter().collect();
sorted.sort_by_key(|t| &t.name);
for table in sorted {
let name = ident(&table.name, false)?;
let target = format!("{schema_ident}.tables.{name}");
let decoration = emitter.decoration(&format!("{target}.Row"), true, false);
let fields = emitter.fields(
&table.columns,
3,
if table.kind == TableKind::Table {
"row"
} else {
"view"
},
&target,
)?;
let runtime = emitter.runtime.clone();
let wire_name = &table.name;
let mut writes = TokenStream::new();
if table.kind == TableKind::Table {
for (rust_name, mode) in [("Insert", "insert"), ("Update", "update")] {
let default = mode == "update"
|| table
.columns
.iter()
.filter(|c| !c.generated && c.identity != Identity::Always)
.all(|c| {
c.nullable || c.has_default || c.identity == Identity::ByDefault
});
let decoration =
emitter.decoration(&format!("{target}.{rust_name}"), false, default);
let fields = emitter.fields(&table.columns, 3, mode, &target)?;
let rust_name = Ident::new(rust_name, Span::call_site());
writes.extend(quote!(#decoration pub struct #rust_name { #fields }));
}
}
tables.extend(quote!(pub mod #name { #[allow(unused_imports)] use super::*; #decoration pub struct Row { #fields } impl #runtime::Relation for Row { const SCHEMA: &'static str = #schema_name; const NAME: &'static str = #wire_name; } #writes }));
}
let mut functions = TokenStream::new();
let mut groups: BTreeMap<&str, Vec<&Function>> = BTreeMap::new();
for function in &schema.functions {
groups.entry(&function.name).or_default().push(function);
}
let mut function_names = BTreeSet::new();
for (wire_name, mut overloads) in groups {
overloads.sort_by_key(|f| {
f.arguments
.iter()
.map(|a| format!("{}:{:?}", a.name, a.ty))
.collect::<Vec<_>>()
});
let count = overloads.len();
let mut signatures = BTreeSet::new();
for (index, function) in overloads.into_iter().enumerate() {
let signature = function
.arguments
.iter()
.map(|a| format!("{}:{:?}", a.name, a.ty))
.collect::<Vec<_>>();
if !signatures.insert(signature) {
return Err(invalid(format!(
"duplicate RPC signature {schema_name}.{wire_name}"
)));
}
let base = ident(wire_name, false)?.to_string();
let generated = if count == 1 {
base
} else {
format!("{}_{index}", base.strip_prefix("r#").unwrap_or(&base))
};
if !function_names.insert(generated.clone()) {
return Err(invalid(format!(
"RPC module name collision {schema_name}.{generated}"
)));
}
let name =
syn::parse_str::<Ident>(&generated).map_err(|e| invalid(e.to_string()))?;
let target = format!("{schema_ident}.functions.{name}");
unique(
function.arguments.iter().map(|a| a.name.as_str()),
false,
&target,
)?;
let decoration = emitter.decoration(
&format!("{target}.Args"),
false,
function.arguments.iter().all(|a| a.has_default),
);
let mut args = TokenStream::new();
for argument in &function.arguments {
let field = ident(&argument.name, false)?;
let wire = &argument.name;
let base = emitter.ty(&argument.ty, 3)?;
if argument.has_default {
let runtime = &emitter.runtime;
let skip = format!(
"{}::Field::is_omit",
quote!(#runtime).to_string().replace(' ', "")
);
args.extend(quote!(#[serde(rename = #wire, skip_serializing_if = #skip)] pub #field: #runtime::Field<::std::option::Option<#base>>,));
} else {
args.extend(quote!(#[serde(rename = #wire)] pub #field: ::std::option::Option<#base>,));
}
}
let (record, returns) = emitter.function_returns(function, &target)?;
let runtime = &emitter.runtime;
functions.extend(quote!(pub mod #name { #[allow(unused_imports)] use super::*; #decoration pub struct Args { #args } #record pub type Returns = #returns; pub struct Function; impl #runtime::Function for Function { type Args = Args; type Returns = Returns; const SCHEMA: &'static str = #schema_name; const NAME: &'static str = #wire_name; } }));
}
}
modules.extend(quote!(pub mod #schema_ident { #[allow(unused_imports)] use super::*; pub mod enums { #[allow(unused_imports)] use super::*; #enums } pub mod composites { #[allow(unused_imports)] use super::*; #composites } pub mod tables { #[allow(unused_imports)] use super::*; #tables } pub mod functions { #[allow(unused_imports)] use super::*; #functions } }));
}
for target in emitter.config.type_attributes.keys() {
if !emitter.used_targets.contains(target) {
return Err(invalid(format!(
"unknown generated type attribute target {target:?}"
)));
}
}
let file = syn::parse2::<syn::File>(quote!(#prelude #aliases #modules))
.map_err(|e| invalid(format!("generated Rust is invalid: {e}")))?;
Ok(prettyplease::unparse(&file))
}
#[cfg(test)]
#[path = "emitter_tests.rs"]
mod tests;