tank_postgres/
connection.rs

1use crate::{
2    PostgresDriver, PostgresPrepared, PostgresTransaction, ValueWrap,
3    util::{
4        postgres_type_to_value, stream_postgres_row_to_tank_row,
5        stream_postgres_simple_query_message_to_tank_query_result, value_to_postgres_type,
6    },
7};
8use async_stream::try_stream;
9use openssl::ssl::{SslConnector, SslFiletype, SslMethod, SslVerifyMode};
10use postgres_openssl::MakeTlsConnector;
11use postgres_types::ToSql;
12use std::{
13    borrow::Cow,
14    env, mem,
15    path::PathBuf,
16    pin::{Pin, pin},
17    str::FromStr,
18};
19use tank_core::{
20    AsQuery, Connection, Driver, Entity, Error, ErrorContext, Executor, Query, QueryResult, Result,
21    RowsAffected, Transaction,
22    future::Either,
23    stream::{Stream, StreamExt, TryStreamExt},
24    truncate_long,
25};
26use tokio::{spawn, task::JoinHandle};
27use tokio_postgres::{NoTls, binary_copy::BinaryCopyInWriter};
28
29/// Connection wrapper for Postgres/Tokio Postgres client.
30///
31/// Manages the client handle and background task used to drive the connection
32/// and implements `Executor` for running queries against Postgres.
33#[derive(Debug)]
34pub struct PostgresConnection {
35    pub(crate) client: tokio_postgres::Client,
36    pub(crate) handle: JoinHandle<()>,
37    pub(crate) _transaction: bool,
38}
39
40impl Executor for PostgresConnection {
41    type Driver = PostgresDriver;
42
43    async fn prepare(&mut self, sql: String) -> Result<Query<Self::Driver>> {
44        let sql = sql.trim_end().trim_end_matches(';');
45        Ok(
46            PostgresPrepared::new(self.client.prepare(&sql).await.map_err(|e| {
47                let error = Error::new(e).context(format!(
48                    "While preparing the query:\n{}",
49                    truncate_long!(sql)
50                ));
51                log::error!("{:#}", error);
52                error
53            })?)
54            .into(),
55        )
56    }
57
58    fn run<'s>(
59        &'s mut self,
60        query: impl AsQuery<Self::Driver> + 's,
61    ) -> impl Stream<Item = Result<QueryResult>> + Send {
62        let mut query = query.as_query();
63        let context = format!("While running the query:\n{}", query.as_mut());
64        let mut owned = mem::take(query.as_mut());
65        match owned {
66            Query::Raw(sql) => {
67                Either::Left(stream_postgres_simple_query_message_to_tank_query_result(
68                    async move || self.client.simple_query_raw(&sql).await.map_err(Into::into),
69                ))
70            }
71            Query::Prepared(..) => Either::Right(try_stream! {
72                let mut transaction = self.begin().await?;
73                {
74                    let mut stream = pin!(transaction.run(&mut owned));
75                    while let Some(value) = stream.next().await.transpose()? {
76                        yield value;
77                    }
78                }
79                transaction.commit().await?;
80                *query.as_mut() = mem::take(&mut owned);
81            }),
82        }
83        .map_err(move |e: Error| {
84            let error = e.context(context.clone());
85            log::error!("{:#}", error);
86            error
87        })
88    }
89
90    fn fetch<'s>(
91        &'s mut self,
92        query: impl AsQuery<Self::Driver> + 's,
93    ) -> impl Stream<Item = Result<tank_core::RowLabeled>> + Send {
94        let mut query = query.as_query();
95        let context = format!("While fetching the query:\n{}", query.as_mut());
96        let owned = mem::take(query.as_mut());
97        stream_postgres_row_to_tank_row(async move || {
98            let row_stream = match owned {
99                Query::Raw(mut sql) => {
100                    let stream = self
101                        .client
102                        .query_raw(&sql, Vec::<ValueWrap>::new())
103                        .await
104                        .map_err(|e| Error::new(e).context(context.clone()))?;
105                    *query.as_mut() = Query::Raw(mem::take(&mut sql));
106                    stream
107                }
108                Query::Prepared(mut prepared) => {
109                    let mut params = prepared.take_params();
110                    let types = prepared.statement.params();
111
112                    for (i, param) in params.iter_mut().enumerate() {
113                        *param = ValueWrap(Cow::Owned(
114                            mem::take(param)
115                                .take_value()
116                                .try_as(&postgres_type_to_value(&types[i]))?,
117                        ));
118                    }
119                    let stream = self
120                        .client
121                        .query_raw(&prepared.statement, params)
122                        .await
123                        .map_err(|e| Error::new(e).context(context.clone()))?;
124                    *query.as_mut() = Query::Prepared(prepared);
125                    stream
126                }
127            };
128            Ok(row_stream).map_err(|e| {
129                log::error!("{:#}", e);
130                e
131            })
132        })
133    }
134
135    async fn append<'a, E, It>(&mut self, entities: It) -> Result<RowsAffected>
136    where
137        E: Entity + 'a,
138        It: IntoIterator<Item = &'a E> + Send,
139        <It as IntoIterator>::IntoIter: Send,
140    {
141        let context = || format!("While appending to the table `{}`", E::table().full_name());
142        let mut result = RowsAffected {
143            rows_affected: Some(0),
144            last_affected_id: None,
145        };
146        let writer = self.driver().sql_writer();
147        let mut sql = String::new();
148        writer.write_copy::<E>(&mut sql);
149        let sink = self.client.copy_in(&sql).await.with_context(context)?;
150        let types: Vec<_> = E::columns()
151            .into_iter()
152            .map(|c| value_to_postgres_type(&c.value))
153            .collect();
154        let writer = BinaryCopyInWriter::new(sink, &types);
155        let mut writer = pin!(writer);
156        let columns_len = E::columns().len();
157        let mut values = Vec::<ValueWrap>::with_capacity(columns_len);
158        let mut refs = Vec::<&(dyn ToSql + Sync)>::with_capacity(columns_len);
159        for entity in entities.into_iter() {
160            values.extend(
161                entity
162                    .row_full()
163                    .into_iter()
164                    .map(|v| ValueWrap(Cow::Owned(v))),
165            );
166            refs.extend(
167                values
168                    .iter()
169                    .map(|v| unsafe { &*(v as &(dyn ToSql + Sync) as *const _) }),
170            );
171            Pin::as_mut(&mut writer)
172                .write(&refs)
173                .await
174                .with_context(context)?;
175            refs.clear();
176            values.clear();
177            *result.rows_affected.as_mut().unwrap() += 1;
178        }
179        writer.finish().await.with_context(context)?;
180        Ok(result)
181    }
182}
183
184impl Connection for PostgresConnection {
185    #[allow(refining_impl_trait)]
186    async fn connect(url: Cow<'static, str>) -> Result<PostgresConnection> {
187        let context = format!("While trying to connect to `{}`", truncate_long!(url));
188        let mut url = Self::sanitize_url(url)?;
189        let mut take_url_param = |key: &str, env_var: &str, remove: bool| {
190            let value = url
191                .query_pairs()
192                .find_map(|(k, v)| if k == key { Some(v) } else { None })
193                .map(|v| v.to_string());
194            if remove && let Some(..) = value {
195                let mut result = url.clone();
196                result.set_query(None);
197                result
198                    .query_pairs_mut()
199                    .extend_pairs(url.query_pairs().filter(|(k, _)| k != key));
200                url = result;
201            };
202            value.or_else(|| env::var(env_var).ok().map(Into::into))
203        };
204        let sslmode = take_url_param("sslmode", "PGSSLMODE", false).unwrap_or("disable".into());
205        let (client, handle) = if sslmode == "disable" {
206            let (client, connection) = tokio_postgres::connect(url.as_str(), NoTls).await?;
207            let handle = spawn(async move {
208                if let Err(error) = connection.await
209                    && !error.is_closed()
210                {
211                    log::error!("Postgres connection error: {:#?}", error);
212                }
213            });
214            (client, handle)
215        } else {
216            let mut builder = SslConnector::builder(SslMethod::tls())?;
217            let path = PathBuf::from_str(
218                take_url_param("sslrootcert", "PGSSLROOTCERT", true)
219                    .as_deref()
220                    .unwrap_or("~/.postgresql/root.crt"),
221            )
222            .with_context(|| context.clone())?;
223            if path.exists() {
224                builder.set_ca_file(path)?;
225            }
226            let path = PathBuf::from_str(
227                take_url_param("sslcert", "PGSSLCERT", true)
228                    .as_deref()
229                    .unwrap_or("~/.postgresql/postgresql.crt"),
230            )
231            .with_context(|| context.clone())?;
232            if path.exists() {
233                builder.set_certificate_chain_file(path)?;
234            }
235            let path = PathBuf::from_str(
236                take_url_param("sslkey", "PGSSLKEY", true)
237                    .as_deref()
238                    .unwrap_or("~/.postgresql/postgresql.key"),
239            )
240            .with_context(|| context.clone())?;
241            if path.exists() {
242                builder.set_private_key_file(path, SslFiletype::PEM)?;
243            }
244            builder.set_verify(SslVerifyMode::PEER);
245            let connector = MakeTlsConnector::new(builder.build());
246            let (client, connection) = tokio_postgres::connect(url.as_str(), connector).await?;
247            let handle = spawn(async move {
248                if let Err(error) = connection.await
249                    && !error.is_closed()
250                {
251                    log::error!("Postgres connection error: {:#?}", error);
252                }
253            });
254            (client, handle)
255        };
256        Ok(Self {
257            client,
258            handle,
259            _transaction: false,
260        })
261    }
262
263    #[allow(refining_impl_trait)]
264    fn begin(&mut self) -> impl Future<Output = Result<PostgresTransaction<'_>>> {
265        PostgresTransaction::new(self)
266    }
267
268    #[allow(refining_impl_trait)]
269    async fn disconnect(self) -> Result<()> {
270        drop(self.client);
271        if let Err(e) = self.handle.await {
272            let error = Error::new(e).context("While disconnecting from Postgres");
273            log::error!("{:#}", error);
274            return Err(error);
275        }
276        Ok(())
277    }
278}
tank_postgres/connection.rs

tank_postgres/
connection.rs
