sea_orm/database/stream/
query.rs

1#![allow(missing_docs, unreachable_code, unused_variables)]
2
3use std::{pin::Pin, task::Poll};
4use tracing::instrument;
5
6#[cfg(feature = "sqlx-dep")]
7use futures_util::TryStreamExt;
8
9#[cfg(feature = "sqlx-dep")]
10use sqlx::Executor;
11
12use super::metric::MetricStream;
13#[cfg(feature = "sqlx-dep")]
14use crate::driver::*;
15use crate::{DbErr, InnerConnection, QueryResult, Statement};
16
17/// Creates a stream from a [QueryResult]
18#[ouroboros::self_referencing]
19pub struct QueryStream {
20    stmt: Statement,
21    conn: InnerConnection,
22    metric_callback: Option<crate::metric::Callback>,
23    #[borrows(mut conn, stmt, metric_callback)]
24    #[not_covariant]
25    stream: MetricStream<'this>,
26}
27
28impl std::fmt::Debug for QueryStream {
29    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
30        write!(f, "QueryStream")
31    }
32}
33
34impl QueryStream {
35    #[allow(dead_code)]
36    #[instrument(level = "trace", skip(metric_callback))]
37    pub(crate) fn build(
38        stmt: Statement,
39        conn: InnerConnection,
40        metric_callback: Option<crate::metric::Callback>,
41    ) -> QueryStream {
42        QueryStreamBuilder {
43            stmt,
44            conn,
45            metric_callback,
46            stream_builder: |conn, stmt, _metric_callback| match conn {
47                #[cfg(feature = "sqlx-mysql")]
48                InnerConnection::MySql(c) => {
49                    let query = crate::driver::sqlx_mysql::sqlx_query(stmt);
50                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
51                    let stream = c
52                        .fetch(query)
53                        .map_ok(Into::into)
54                        .map_err(sqlx_error_to_query_err);
55                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
56                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
57                }
58                #[cfg(feature = "sqlx-postgres")]
59                InnerConnection::Postgres(c) => {
60                    let query = crate::driver::sqlx_postgres::sqlx_query(stmt);
61                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
62                    let stream = c
63                        .fetch(query)
64                        .map_ok(Into::into)
65                        .map_err(sqlx_error_to_query_err);
66                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
67                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
68                }
69                #[cfg(feature = "sqlx-sqlite")]
70                InnerConnection::Sqlite(c) => {
71                    let query = crate::driver::sqlx_sqlite::sqlx_query(stmt);
72                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
73                    let stream = c
74                        .fetch(query)
75                        .map_ok(Into::into)
76                        .map_err(sqlx_error_to_query_err);
77                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
78                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
79                }
80                #[cfg(feature = "rusqlite")]
81                InnerConnection::Rusqlite(conn) => {
82                    use itertools::Either;
83                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
84                    let stream = match conn.stream(stmt) {
85                        Ok(rows) => Either::Left(rows.into_iter().map(Ok)),
86                        Err(err) => Either::Right(std::iter::once(Err(err))),
87                    };
88                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
89                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
90                }
91                #[cfg(feature = "mock")]
92                InnerConnection::Mock(c) => {
93                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
94                    let stream = c.fetch(stmt);
95                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
96                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
97                }
98                #[cfg(feature = "proxy")]
99                InnerConnection::Proxy(c) => {
100                    let start = _metric_callback.is_some().then(std::time::SystemTime::now);
101                    let stream = futures_util::stream::once({
102                        Err(DbErr::BackendNotSupported {
103                            db: "Proxy",
104                            ctx: "QueryStream",
105                        })
106                    });
107                    let elapsed = start.map(|s| s.elapsed().unwrap_or_default());
108                    MetricStream::new(_metric_callback, stmt, elapsed, stream)
109                }
110                #[allow(unreachable_patterns)]
111                _ => unreachable!(),
112            },
113        }
114        .build()
115    }
116}
117
118#[cfg(not(feature = "sync"))]
119impl Stream for QueryStream {
120    type Item = Result<QueryResult, DbErr>;
121
122    fn poll_next(
123        self: Pin<&mut Self>,
124        cx: &mut std::task::Context<'_>,
125    ) -> Poll<Option<Self::Item>> {
126        let this = self.get_mut();
127        this.with_stream_mut(|stream| Pin::new(stream).poll_next(cx))
128    }
129}
130
131#[cfg(feature = "sync")]
132impl Iterator for QueryStream {
133    type Item = Result<QueryResult, DbErr>;
134
135    fn next(&mut self) -> Option<Self::Item> {
136        self.with_stream_mut(|stream| stream.next())
137    }
138}
sea_orm/database/stream/query.rs

sea_orm/database/stream/
query.rs
