forked from transact-rs/sqlx
-
Notifications
You must be signed in to change notification settings - Fork 17
Expand file tree
/
Copy pathquery_as.rs
More file actions
211 lines (192 loc) 路 5.74 KB
/
Copy pathquery_as.rs
File metadata and controls
211 lines (192 loc) 路 5.74 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
use std::marker::PhantomData;
use either::Either;
use futures_core::stream::BoxStream;
use futures_util::{StreamExt, TryStreamExt};
use crate::arguments::IntoArguments;
use crate::database::{Database, HasArguments, HasStatement};
use crate::encode::Encode;
use crate::error::Error;
use crate::executor::{Execute, Executor};
use crate::from_row::FromRow;
use crate::query::{query, query_statement, query_statement_with, query_with, Query};
use crate::types::Type;
/// Raw SQL query with bind parameters, mapped to a concrete type using [`FromRow`].
/// Returned from [`query_as`].
#[must_use = "query must be executed to affect database"]
pub struct QueryAs<'q, DB: Database, O, A> {
pub(crate) inner: Query<'q, DB, A>,
pub(crate) output: PhantomData<O>,
}
impl<'q, DB, O: Send, A: Send> Execute<'q, DB> for QueryAs<'q, DB, O, A>
where
DB: Database,
A: 'q + IntoArguments<'q, DB>,
{
#[inline]
fn sql(&self) -> &'q str {
self.inner.sql()
}
#[inline]
fn statement(&self) -> Option<&<DB as HasStatement<'q>>::Statement> {
self.inner.statement()
}
#[inline]
fn take_arguments(&mut self) -> Option<<DB as HasArguments<'q>>::Arguments> {
self.inner.take_arguments()
}
#[inline]
fn persistent(&self) -> bool {
self.inner.persistent()
}
}
impl<'q, DB: Database, O> QueryAs<'q, DB, O, <DB as HasArguments<'q>>::Arguments> {
/// Bind a value for use with this SQL query.
///
/// See [`Query::bind`](crate::query::Query::bind).
pub fn bind<T: 'q + Send + Encode<'q, DB> + Type<DB>>(mut self, value: T) -> Self {
self.inner = self.inner.bind(value);
self
}
}
// FIXME: This is very close, nearly 1:1 with `Map`
// noinspection DuplicatedCode
impl<'q, DB, O, A> QueryAs<'q, DB, O, A>
where
DB: Database,
A: 'q + IntoArguments<'q, DB>,
O: Send + Unpin + for<'r> FromRow<'r, DB::Row>,
{
/// Execute the query and return the generated results as a stream.
pub fn fetch<'e, 'c: 'e, E>(self, executor: E) -> BoxStream<'e, Result<O, Error>>
where
'q: 'e,
E: 'e + Executor<'c, Database = DB>,
DB: 'e,
O: 'e,
A: 'e,
{
self.fetch_many(executor)
.try_filter_map(|step| async move { Ok(step.right()) })
.boxed()
}
/// Execute multiple queries and return the generated results as a stream
/// from each query, in a stream.
pub fn fetch_many<'e, 'c: 'e, E>(
self,
executor: E,
) -> BoxStream<'e, Result<Either<DB::Done, O>, Error>>
where
'q: 'e,
E: 'e + Executor<'c, Database = DB>,
DB: 'e,
O: 'e,
A: 'e,
{
Box::pin(try_stream! {
let mut s = executor.fetch_many(self.inner);
while let Some(v) = s.try_next().await? {
r#yield!(match v {
Either::Left(v) => Either::Left(v),
Either::Right(row) => Either::Right(O::from_row(&row)?),
});
}
Ok(())
})
}
/// Execute the query and return all the generated results, collected into a [`Vec`].
#[inline]
pub async fn fetch_all<'e, 'c: 'e, E>(self, executor: E) -> Result<Vec<O>, Error>
where
'q: 'e,
E: 'e + Executor<'c, Database = DB>,
DB: 'e,
O: 'e,
A: 'e,
{
self.fetch(executor).try_collect().await
}
/// Execute the query and returns exactly one row.
pub async fn fetch_one<'e, 'c: 'e, E>(self, executor: E) -> Result<O, Error>
where
'q: 'e,
E: 'e + Executor<'c, Database = DB>,
DB: 'e,
O: 'e,
A: 'e,
{
self.fetch_optional(executor)
.await
.and_then(|row| row.ok_or(Error::RowNotFound))
}
/// Execute the query and returns at most one row.
pub async fn fetch_optional<'e, 'c: 'e, E>(self, executor: E) -> Result<Option<O>, Error>
where
'q: 'e,
E: 'e + Executor<'c, Database = DB>,
DB: 'e,
O: 'e,
A: 'e,
{
let row = executor.fetch_optional(self.inner).await?;
if let Some(row) = row {
O::from_row(&row).map(Some)
} else {
Ok(None)
}
}
}
/// Make a SQL query that is mapped to a concrete type
/// using [`FromRow`].
#[inline]
pub fn query_as<'q, DB, O>(sql: &'q str) -> QueryAs<'q, DB, O, <DB as HasArguments<'q>>::Arguments>
where
DB: Database,
O: for<'r> FromRow<'r, DB::Row>,
{
QueryAs {
inner: query(sql),
output: PhantomData,
}
}
/// Make a SQL query, with the given arguments, that is mapped to a concrete type
/// using [`FromRow`].
#[inline]
pub fn query_as_with<'q, DB, O, A>(sql: &'q str, arguments: A) -> QueryAs<'q, DB, O, A>
where
DB: Database,
A: IntoArguments<'q, DB>,
O: for<'r> FromRow<'r, DB::Row>,
{
QueryAs {
inner: query_with(sql, arguments),
output: PhantomData,
}
}
// Make a SQL query from a statement, that is mapped to a concrete type.
pub(crate) fn query_statement_as<'q, DB, O>(
statement: &'q <DB as HasStatement<'q>>::Statement,
) -> QueryAs<'q, DB, O, <DB as HasArguments<'_>>::Arguments>
where
DB: Database,
O: for<'r> FromRow<'r, DB::Row>,
{
QueryAs {
inner: query_statement(statement),
output: PhantomData,
}
}
// Make a SQL query from a statement, with the given arguments, that is mapped to a concrete type.
pub(crate) fn query_statement_as_with<'q, DB, O, A>(
statement: &'q <DB as HasStatement<'q>>::Statement,
arguments: A,
) -> QueryAs<'q, DB, O, A>
where
DB: Database,
A: IntoArguments<'q, DB>,
O: for<'r> FromRow<'r, DB::Row>,
{
QueryAs {
inner: query_statement_with(statement, arguments),
output: PhantomData,
}
}