sea_orm/database/stream/
query.rs

1#![allow(missing_docs, unreachable_code, unused_variables)]
2
3use tracing::instrument;
4
5#[cfg(feature = "sqlx-dep")]
6use futures_util::TryStreamExt;
7
8#[cfg(feature = "sqlx-dep")]
9use sqlx::Executor;
10
11use super::metric::MetricStream;
12#[cfg(feature = "sqlx-dep")]
13use crate::driver::*;
14use crate::{DbErr, InnerConnection, QueryResult, Statement};
15
16/// Creates a stream from a [QueryResult]
17#[ouroboros::self_referencing]
18pub struct QueryStream {
19    stmt: Statement,
20    conn: InnerConnection,
21    metric_callback: Option<crate::metric::Callback>,
22    #[borrows(mut conn, stmt, metric_callback)]
23    #[not_covariant]
24    stream: MetricStream<'this>,
25}
26
27impl std::fmt::Debug for QueryStream {
28    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
29        write!(f, "QueryStream")
30    }
31}
32
33impl QueryStream {
34    #[allow(dead_code)]
35    #[instrument(level = "trace", skip(metric_callback))]
36    pub(crate) fn build(
37        stmt: Statement,
38        conn: InnerConnection,
39        metric_callback: Option<crate::metric::Callback>,
40    ) -> QueryStream {
41        QueryStreamBuilder {
42            stmt,
43            conn,
44            metric_callback,
45            stream_builder: |conn, stmt, _metric_callback| match conn {
46                #[cfg(feature = "sqlx-mysql")]
47                InnerConnection::MySql(c) => {
48                    let query = crate::driver::sqlx_mysql::sqlx_query(stmt);
49                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
50                    let stream = c
51                        .fetch(query)
52                        .map_ok(Into::into)
53                        .map_err(sqlx_error_to_query_err);
54                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
55                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
56                }
57                #[cfg(feature = "sqlx-postgres")]
58                InnerConnection::Postgres(c) => {
59                    let query = crate::driver::sqlx_postgres::sqlx_query(stmt);
60                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
61                    let stream = c
62                        .fetch(query)
63                        .map_ok(Into::into)
64                        .map_err(sqlx_error_to_query_err);
65                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
66                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
67                }
68                #[cfg(feature = "sqlx-sqlite")]
69                InnerConnection::Sqlite(c) => {
70                    let query = crate::driver::sqlx_sqlite::sqlx_query(stmt);
71                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
72                    let stream = c
73                        .fetch(query)
74                        .map_ok(Into::into)
75                        .map_err(sqlx_error_to_query_err);
76                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
77                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
78                }
79                #[cfg(feature = "rusqlite")]
80                InnerConnection::Rusqlite(conn) => {
81                    use itertools::Either;
82                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
83                    let stream = match conn.stream(stmt) {
84                        Ok(rows) => Either::Left(rows.into_iter().map(Ok)),
85                        Err(err) => Either::Right(std::iter::once(Err(err))),
86                    };
87                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
88                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
89                }
90                #[cfg(feature = "mock")]
91                InnerConnection::Mock(c) => {
92                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
93                    let stream = c.fetch(stmt);
94                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
95                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
96                }
97                #[cfg(feature = "proxy")]
98                InnerConnection::Proxy(c) => {
99                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
100                    let stream = futures_util::stream::once({
101                        Err(DbErr::BackendNotSupported {
102                            db: "Proxy",
103                            ctx: "QueryStream",
104                        })
105                    });
106                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
107                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
108                }
109                #[allow(unreachable_patterns)]
110                _ => unreachable!(),
111            },
112        }
113        .build()
114    }
115}
116
117#[cfg(not(feature = "sync"))]
118impl Stream for QueryStream {
119    type Item = Result<QueryResult, DbErr>;
120
121    fn poll_next(
122        self: Pin<&mut Self>,
123        cx: &mut std::task::Context<'_>,
124    ) -> Poll<Option<Self::Item>> {
125        let this = self.get_mut();
126        this.with_stream_mut(|stream| Pin::new(stream).poll_next(cx))
127    }
128}
129
130#[cfg(feature = "sync")]
131impl Iterator for QueryStream {
132    type Item = Result<QueryResult, DbErr>;
133
134    fn next(&mut self) -> Option<Self::Item> {
135        self.with_stream_mut(|stream| stream.next())
136    }
137}
sea_orm/database/stream/query.rs

sea_orm/database/stream/
query.rs
