1use byteorder::*;
2use std::io::Write;
3use std::num::NonZeroU32;
4
5use crate::deserialize::{self, FromSql, Queryable};
6use crate::expression::{
7 AppearsOnTable, AsExpression, Expression, SelectableExpression, TypedExpressionType,
8 ValidGrouping,
9};
10use crate::pg::{Pg, PgValue};
11use crate::query_builder::bind_collector::ByteWrapper;
12use crate::query_builder::{AstPass, QueryFragment, QueryId};
13use crate::result::QueryResult;
14use crate::serialize::{self, IsNull, Output, ToSql, WriteTuple};
15use crate::sql_types::{HasSqlType, Record, SqlType};
16
17macro_rules! tuple_impls {
18 ($(
19 $Tuple:tt {
20 $(($idx:tt) -> $T:ident, $ST:ident, $TT:ident,)+
21 }
22 )+) => {$(
23 #[cfg(feature = "postgres_backend")]
24 impl<$($T,)+ $($ST,)+> FromSql<Record<($($ST,)+)>, Pg> for ($($T,)+)
25 where
26 $($T: FromSql<$ST, Pg>,)+
27 {
28 #[allow(clippy::mixed_read_write_in_expression)]
32 fn from_sql(value: PgValue<'_>) -> deserialize::Result<Self> {
33 let mut bytes = value.as_bytes();
34 let num_elements = bytes.read_i32::<NetworkEndian>()?;
35
36 if num_elements != $Tuple {
37 return Err(format!(
38 "Expected a tuple of {} elements, got {}",
39 $Tuple,
40 num_elements,
41 ).into());
42 }
43
44 let result = ($({
45 let oid = NonZeroU32::new(bytes.read_u32::<NetworkEndian>()?).expect("Oid's aren't zero");
50 let num_bytes = bytes.read_i32::<NetworkEndian>()?;
51
52 if num_bytes == -1 {
53 $T::from_nullable_sql(None)?
54 } else {
55 let (elem_bytes, new_bytes) = bytes.split_at(num_bytes.try_into()?);
56 bytes = new_bytes;
57 $T::from_sql(PgValue::new_internal(
58 elem_bytes,
59 &oid,
60 ))?
61 }
62 },)+);
63
64 if bytes.is_empty() {
65 Ok(result)
66 } else {
67 Err("Received too many bytes. This tuple likely contains \
68 an element of the wrong SQL type.".into())
69 }
70 }
71 }
72
73 #[cfg(feature = "postgres_backend")]
74 impl<$($T,)+ $($ST,)+> Queryable<Record<($($ST,)+)>, Pg> for ($($T,)+)
75 where Self: FromSql<Record<($($ST,)+)>, Pg>
76 {
77 type Row = Self;
78
79 fn build(row: Self::Row) -> deserialize::Result<Self> {
80 Ok(row)
81 }
82 }
83
84 #[cfg(feature = "postgres_backend")]
85 impl<$($T,)+ $($ST,)+> AsExpression<Record<($($ST,)+)>> for ($($T,)+)
86 where
87 $($ST: SqlType + TypedExpressionType,)+
88 $($T: AsExpression<$ST>,)+
89 PgTuple<($($T::Expression,)+)>: Expression<SqlType = Record<($($ST,)+)>>,
90 {
91 type Expression = PgTuple<($($T::Expression,)+)>;
92
93 fn as_expression(self) -> Self::Expression {
94 PgTuple(($(
95 self.$idx.as_expression(),
96 )+))
97 }
98 }
99
100 #[cfg(feature = "postgres_backend")]
101 impl<$($T,)+ $($ST,)+> WriteTuple<($($ST,)+)> for ($($T,)+)
102 where
103 $($T: ToSql<$ST, Pg>,)+
104 $(Pg: HasSqlType<$ST>),+
105 {
106 fn write_tuple(&self, out: &mut Output<'_, '_, Pg>) -> serialize::Result {
107 let mut buffer = Vec::new();
108 out.write_i32::<NetworkEndian>($Tuple)?;
109
110 $(
111 let oid = <Pg as HasSqlType<$ST>>::metadata(out.metadata_lookup()).oid()?;
112 out.write_u32::<NetworkEndian>(oid)?;
113 let is_null = {
114 let mut temp_buffer = Output::new(ByteWrapper(&mut buffer), out.metadata_lookup());
115 let is_null = self.$idx.to_sql(&mut temp_buffer)?;
116 is_null
117 };
118
119 if let IsNull::No = is_null {
120 out.write_i32::<NetworkEndian>(buffer.len().try_into()?)?;
121 out.write_all(&buffer)?;
122 buffer.clear();
123 } else {
124 out.write_i32::<NetworkEndian>(-1)?;
125 }
126 )+
127
128 Ok(IsNull::No)
129 }
130 }
131 )+}
132}
133
134diesel_derives::__diesel_for_each_tuple!(tuple_impls);
135
136#[derive(Debug, Clone, Copy, QueryId, ValidGrouping)]
137pub struct PgTuple<T>(T);
138
139impl<T> QueryFragment<Pg> for PgTuple<T>
140where
141 T: QueryFragment<Pg>,
142{
143 fn walk_ast<'b>(&'b self, mut out: AstPass<'_, 'b, Pg>) -> QueryResult<()> {
144 out.push_sql("ROW(");
145 self.0.walk_ast(out.reborrow())?;
146 out.push_sql(")");
147 Ok(())
148 }
149}
150
151impl<T> Expression for PgTuple<T>
152where
153 T: Expression,
154 T::SqlType: 'static,
155{
156 type SqlType = Record<T::SqlType>;
157}
158
159impl<T, QS> SelectableExpression<QS> for PgTuple<T>
160where
161 T: SelectableExpression<QS>,
162 Self: AppearsOnTable<QS>,
163{
164}
165
166impl<T, QS> AppearsOnTable<QS> for PgTuple<T>
167where
168 T: AppearsOnTable<QS>,
169 Self: Expression,
170{
171}
172
173#[cfg(test)]
174mod tests {
175 use super::*;
176 use crate::dsl::sql;
177 use crate::prelude::*;
178 use crate::sql_types::*;
179 use crate::test_helpers::*;
180
181 #[diesel_test_helper::test]
182 fn record_deserializes_correctly() {
183 let conn = &mut pg_connection();
184
185 let tup =
186 sql::<Record<(Integer, Text)>>("SELECT (1, 'hi')").get_result::<(i32, String)>(conn);
187 assert_eq!(Ok((1, String::from("hi"))), tup);
188
189 let tup = sql::<Record<(Record<(Integer, Text)>, Integer)>>("SELECT ((2, 'bye'), 3)")
190 .get_result::<((i32, String), i32)>(conn);
191 assert_eq!(Ok(((2, String::from("bye")), 3)), tup);
192
193 let tup = sql::<
194 Record<(
195 Record<(Nullable<Integer>, Nullable<Text>)>,
196 Nullable<Integer>,
197 )>,
198 >("SELECT ((4, NULL), NULL)")
199 .get_result::<((Option<i32>, Option<String>), Option<i32>)>(conn);
200 assert_eq!(Ok(((Some(4), None), None)), tup);
201
202 let tup = sql::<Record<(Integer,)>>("SELECT ROW(1)").get_result::<(i32,)>(conn);
203 assert_eq!(Ok((1,)), tup);
204 }
205
206 #[diesel_test_helper::test]
207 fn record_kinda_sorta_not_really_serializes_correctly() {
208 let conn = &mut pg_connection();
209
210 let tup = sql::<Record<(Integer, Text)>>("(1, 'hi')");
211 let res = crate::select(tup.eq((1, "hi"))).get_result(conn);
212 assert_eq!(Ok(true), res);
213
214 let tup = sql::<Record<(Record<(Integer, Text)>, Integer)>>("((2, 'bye'::text), 3)");
215 let res = crate::select(tup.eq(((2, "bye"), 3))).get_result(conn);
216 assert_eq!(Ok(true), res);
217
218 let tup = sql::<Record<(Integer,)>>("ROW(3)");
219 let res = crate::select(tup.eq((3,))).get_result(conn);
220 assert_eq!(Ok(true), res);
221
222 let tup = sql::<
223 Record<(
224 Record<(Nullable<Integer>, Nullable<Text>)>,
225 Nullable<Integer>,
226 )>,
227 >("((4, NULL::text), NULL::int4)");
228 let res = crate::select(tup.is_not_distinct_from(((Some(4), None::<&str>), None::<i32>)))
229 .get_result(conn);
230 assert_eq!(Ok(true), res);
231 }
232
233 #[diesel_test_helper::test]
234 fn serializing_named_composite_types() {
235 #[derive(SqlType, QueryId, Debug, Clone, Copy)]
236 #[diesel(postgres_type(name = "my_type"))]
237 struct MyType;
238
239 #[derive(Debug, AsExpression)]
240 #[diesel(sql_type = MyType)]
241 struct MyStruct<'a>(i32, &'a str);
242
243 impl ToSql<MyType, Pg> for MyStruct<'_> {
244 fn to_sql<'b>(&'b self, out: &mut Output<'b, '_, Pg>) -> serialize::Result {
245 WriteTuple::<(Integer, Text)>::write_tuple(&(self.0, self.1), out)
246 }
247 }
248
249 let conn = &mut pg_connection();
250
251 crate::sql_query("CREATE TYPE my_type AS (i int4, t text)")
252 .execute(conn)
253 .unwrap();
254 let sql = sql::<Bool>("(1, 'hi')::my_type = ").bind::<MyType, _>(MyStruct(1, "hi"));
255 let res = crate::select(sql).get_result(conn);
256 assert_eq!(Ok(true), res);
257 }
258}