feat: add transactions

Closes #1

.gitignore

@@ -1 +1,2 @@
-target/
+target/
+.env

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "rust.unstable_features": true
+}

Cargo.lock

@@ -493,7 +493,7 @@ checksum = "692fcb63b64b1758029e0a96ee63e049ce8c5948587f2f7208df04625e5f6b56"
 
 [[package]]
 name = "ood_persistence"
-version = "0.1.1"
+version = "0.2.0"
 dependencies = [
  "async-trait",
  "bb8",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ood_persistence"
-version = "0.1.1"
+version = "0.2.0"
 edition = "2018"
 authors = ["Dmitriy Pleshevskiy <dmitriy@ideascup.me>"]
 repository = "https://github.com/pleshevskiy/ood_persistence"
@@ -11,6 +11,8 @@ license = "MIT OR Apache-2.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 [features]
+nightly = []
+
 async = ["async-trait"]
 sync = []
 

README.md

@@ -20,6 +20,9 @@ authors = ["Me <user@rust-lang.org>"]
 ood_persistence = { version = "0", features = ["bb8_postgres"] }
 ```
 
+In stable rust channel you can use only connection interface, but if you use nightly channel, add an additional
+"nightly" feature to your `Cargo.toml` and you can use transactions as well.
+
 ## Usage
 
 See examples directory.

examples/web/Cargo.toml

@@ -15,7 +15,7 @@ dotenv = { version = "0.15", optional = true }
 async-trait = "0.1"
 
 # database
-ood_persistence = { path = "../../", features = ["bb8_postgres"] }
+ood_persistence = { path = "../../", features = ["nightly", "bb8_postgres"] }
 postgres-types = { version = "0.2", features = ["derive"] }
 
 # runtime

examples/web/Makefile.toml

@@ -0,0 +1,5 @@
+[tasks.dev]
+command = "cargo"
+workspace = false
+args = ["run", "--features", "dev"]
+watch = { watch = ["src", "Cargo.toml", '.env'] }

examples/web/README.md

@@ -0,0 +1,47 @@
+# Web example
+
+Simple rest api example with hyper, bb8, postgres
+
+## Deps
+
+For this example you need to install [docker] with [docker-compose], [nightly rust]. Follow the instructions on the official sites.
+
+[docker]: https://docs.docker.com/get-docker/
+[docker-compose]: https://docs.docker.com/compose/install/
+[nightly rust]: https://www.rust-lang.org/tools/install
+
+## Running
+
+Move to the example directory
+
+```sh
+cd examples/web
+```
+
+Run configuration for docker-compose
+
+```sh
+docker-compose -f docker-compose.dev.yml up
+```
+
+Or run postgres server manually.
+
+Then copy `.env.example` to `.env` and edit if you needed.
+
+```sh
+cp .env.example .env
+```
+
+Now you can run server
+
+```sh
+cargo run --features dev
+```
+
+Or if you have a [cargo make]
+
+```sh
+cargo make dev
+```
+
+[cargo make]: https://github.com/sagiegurari/cargo-make

examples/web/src/app/list/controller.rs

@@ -12,6 +12,11 @@ pub fn create_postgres_list_controller(
     }
 }
 
+#[derive(Debug, Deserialize)]
+pub struct AddListInput {
+    name: String,
+}
+
 pub struct ListController<P>
 where
     P: PersistencePool,
@@ -29,4 +34,8 @@ where
             _ => Ok(None),
         }
     }
+
+    pub async fn add_list(&self, input: AddListInput) -> ApiResult<List> {
+        self.list_service.add_list(&input.name).await
+    }
 }

examples/web/src/app/list/service.rs

@@ -1,7 +1,9 @@
 use super::storage_type::ListStorage;
 use super::{List, ListId};
 use crate::db::list::storage::PostgresListStorage;
-use crate::db::persistence::{PersistencePool, PostgresPersistence};
+use crate::db::persistence::{
+    ConnectionClient, PersistencePool, PostgresPersistence, TransactionClient,
+};
 use crate::error::ApiResult;
 
 pub fn create_postgres_list_service(
@@ -30,4 +32,13 @@ where
         let list = self.list_storage.get_list_opt(&mut conn, list_id).await?;
         Ok(list)
     }
+
+    pub async fn add_list(&self, name: &str) -> ApiResult<List> {
+        let mut conn = self.persistence.get_connection().await?;
+
+        let mut trx = conn.start_transaction().await?;
+        let list = self.list_storage.add_list(&mut trx, name).await?;
+        trx.commit().await?;
+        Ok(list)
+    }
 }

examples/web/src/app/list/storage_type.rs

@@ -7,4 +7,6 @@ where
     Conn: ConnectionClient,
 {
     async fn get_list_opt(&self, conn: &mut Conn, id: ListId) -> QueryResult<Option<List>>;
+
+    async fn add_list(&self, conn: &mut Conn::Trx<'_>, name: &str) -> QueryResult<List>;
 }

examples/web/src/db/list/storage.rs

@@ -1,16 +1,18 @@
 use super::DbList;
 use crate::app::list::storage_type::ListStorage;
 use crate::app::list::{List, ListId};
-use crate::db::persistence::{try_get_one, ConnectionClient, PostgresConnection, QueryResult};
+use crate::db::persistence::{
+    try_get_one, ConnectionClient, PostgresConnection, PostgresTransaction, QueryResult,
+};
 use postgres_types::Type;
 
 pub struct PostgresListStorage {}
 
 #[async_trait]
-impl<'c> ListStorage<PostgresConnection<'c>> for PostgresListStorage {
+impl<'p> ListStorage<PostgresConnection<'p>> for PostgresListStorage {
     async fn get_list_opt(
         &self,
-        conn: &mut PostgresConnection<'c>,
+        conn: &mut PostgresConnection<'p>,
         list_id: ListId,
     ) -> QueryResult<Option<List>> {
         let inner_conn = conn.inner();
@@ -26,4 +28,21 @@ impl<'c> ListStorage<PostgresConnection<'c>> for PostgresListStorage {
             .transpose()
             .map_err(From::from)
     }
+
+    async fn add_list(&self, conn: &mut PostgresTransaction<'_>, name: &str) -> QueryResult<List> {
+        let inner_conn = conn.inner();
+
+        let stmt = inner_conn
+            .prepare_typed(
+                "insert into lists as l (name) values ($1) returning l",
+                &[Type::TEXT],
+            )
+            .await?;
+
+        inner_conn
+            .query_one(&stmt, &[&name])
+            .await
+            .and_then(try_get_one::<DbList, _>)
+            .map_err(From::from)
+    }
 }

examples/web/src/db/persistence.rs

@@ -2,10 +2,10 @@ use crate::config;
 use ood_persistence::bb8_postgres::{tokio_postgres, NoTlsManager};
 pub use ood_persistence::bb8_postgres::{
     NoTlsConnection as PostgresConnection, NoTlsPersistence as PostgresPersistence,
-    NoTlsPool as PostgresPool,
+    NoTlsPool as PostgresPool, Transaction as PostgresTransaction,
 };
 pub use ood_persistence::{
-    asyn::{ConnectionClient, PersistencePool},
+    asyn::{ConnectionClient, PersistencePool, TransactionClient},
     error::Result as QueryResult,
 };
 

examples/web/src/lib.rs

@@ -1,4 +1,4 @@
-#![allow(dead_code)]
+#![deny(clippy::all)]
 
 #[macro_use]
 extern crate postgres_types;

examples/web/src/rest/routes/api/list.rs

@@ -1,15 +1,19 @@
 use crate::app::list::controller::create_postgres_list_controller;
 use crate::rest::routes::*;
-use crate::rest::server_utils::{create_not_found_err_json_response, create_ok_json_response};
+use crate::rest::server_utils::{
+    create_not_found_err_json_response, create_ok_json_response, deserialize_request_body,
+};
 
 pub enum Router {
     GetListById(String),
+    AddList,
 }
 
 impl MaybeFrom<RouteParts<'_>> for Router {
     fn maybe_from((method, uri_path_parts): RouteParts<'_>) -> Option<Self> {
         match (method, uri_path_parts) {
             (&Method::GET, [list_id]) => Some(Self::GetListById(list_id.to_string())),
+            (&Method::POST, []) => Some(Self::AddList),
             _ => None,
         }
     }
@@ -27,6 +31,11 @@ impl Resolver for Router {
                     None => create_not_found_err_json_response("List not found"),
                 }
             }
+            Self::AddList => {
+                let input = deserialize_request_body(vars.body).await?;
+                let res = controller.add_list(input).await?;
+                create_ok_json_response(res)
+            }
         }
     }
 }

examples/web/src/rest/server_utils.rs

@@ -1,8 +1,7 @@
-use crate::error::StdResult;
 use crate::rest::prelude::*;
 use serde::{de, ser};
 
-pub async fn deserialize_request_body<T>(req_body: Body) -> StdResult<T>
+pub async fn deserialize_request_body<T>(req_body: Body) -> ApiResult<T>
 where
     T: de::DeserializeOwned,
 {

examples/web/src/rest/types.rs

@@ -9,8 +9,8 @@ pub type QueryParams<'a> = HashMap<&'a str, &'a str>;
 
 #[derive(Debug)]
 pub struct ReqVariables<'params> {
-    body: Body,
-    query_params: QueryParams<'params>,
+    pub body: Body,
+    pub query_params: QueryParams<'params>,
 }
 
 impl<'params> ReqVariables<'params> {

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "nightly"

src/asyn.rs

@@ -7,8 +7,23 @@ pub trait PersistencePool: Send + Sync {
     async fn get_connection(&self) -> error::Result<Self::Conn>;
 }
 
+#[cfg_attr(feature = "nightly", async_trait)]
 pub trait ConnectionClient {
     type InnerConn;
 
+    #[cfg(feature = "nightly")]
+    type Trx<'t>: TransactionClient;
+
     fn inner(&mut self) -> &mut Self::InnerConn;
+
+    #[cfg(feature = "nightly")]
+    async fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>>;
+}
+
+#[cfg(feature = "nightly")]
+#[async_trait]
+pub trait TransactionClient: ConnectionClient {
+    async fn commit(self) -> error::Result<()>;
+
+    async fn rollback(self) -> error::Result<()>;
 }

src/bb8_postgres.rs

@@ -1,3 +1,5 @@
+#[cfg(feature = "nightly")]
+use crate::asyn::TransactionClient;
 use crate::asyn::{ConnectionClient, PersistencePool};
 use crate::error;
 
@@ -5,13 +7,15 @@ pub use bb8::{Pool, PooledConnection};
 pub use bb8_postgres::tokio_postgres;
 pub use bb8_postgres::PostgresConnectionManager as Manager;
 
+pub type InnerConn<'p, M> = PooledConnection<'p, M>;
+pub type InnerTrx<'p> = tokio_postgres::Transaction<'p>;
+
 pub type NoTlsManager = Manager<tokio_postgres::NoTls>;
 pub type NoTlsPersistence<'p> = Persistence<'p, NoTlsManager>;
 pub type NoTlsConnection<'p> = Connection<'p, NoTlsManager>;
+pub type NoTlsInnerConn<'p> = InnerConn<'p, NoTlsManager>;
 pub type NoTlsPool = Pool<NoTlsManager>;
 
-pub type InnerConn<'p, M> = PooledConnection<'p, M>;
-
 pub fn new<M>(pool: &Pool<M>) -> Persistence<M>
 where
     M: bb8::ManageConnection,
@@ -20,14 +24,13 @@ where
 }
 
 #[derive(Clone)]
-pub struct Persistence<'p, M: bb8::ManageConnection>(&'p Pool<M>);
+pub struct Persistence<'p, M>(&'p Pool<M>)
+where
+    M: bb8::ManageConnection;
 
 #[async_trait]
-impl<'p, M> PersistencePool for Persistence<'p, M>
-where
-    M: bb8::ManageConnection + Send + Sync,
-{
-    type Conn = Connection<'p, M>;
+impl<'p> PersistencePool for NoTlsPersistence<'p> {
+    type Conn = NoTlsConnection<'p>;
 
     async fn get_connection(&self) -> error::Result<Self::Conn> {
         self.0
@@ -38,15 +41,68 @@ where
     }
 }
 
-pub struct Connection<'p, M: bb8::ManageConnection>(InnerConn<'p, M>);
-
-impl<'c, M> ConnectionClient for Connection<'c, M>
+pub struct Connection<'p, M>(InnerConn<'p, M>)
 where
-    M: bb8::ManageConnection,
-{
-    type InnerConn = InnerConn<'c, M>;
+    M: bb8::ManageConnection;
+
+#[cfg_attr(feature = "nightly", async_trait)]
+impl<'me> ConnectionClient for NoTlsConnection<'me> {
+    type InnerConn = NoTlsInnerConn<'me>;
+
+    #[cfg(feature = "nightly")]
+    type Trx<'t> = Transaction<'t>;
 
     fn inner(&mut self) -> &mut Self::InnerConn {
         &mut self.0
     }
+
+    #[cfg(feature = "nightly")]
+    async fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>> {
+        self.0
+            .transaction()
+            .await
+            .map_err(|_| error::PersistenceError::UpgradeToTransaction)
+            .map(Transaction)
+    }
+}
+
+#[cfg(feature = "nightly")]
+pub struct Transaction<'p>(InnerTrx<'p>);
+
+#[cfg(feature = "nightly")]
+#[async_trait]
+impl<'me> ConnectionClient for Transaction<'me> {
+    type InnerConn = InnerTrx<'me>;
+
+    type Trx<'t> = Transaction<'t>;
+
+    fn inner(&mut self) -> &mut Self::InnerConn {
+        &mut self.0
+    }
+
+    async fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>> {
+        self.0
+            .transaction()
+            .await
+            .map_err(|_| error::PersistenceError::UpgradeToTransaction)
+            .map(Transaction)
+    }
+}
+
+#[cfg(feature = "nightly")]
+#[async_trait]
+impl<'me> TransactionClient for Transaction<'me> {
+    async fn commit(self) -> error::Result<()> {
+        self.0
+            .commit()
+            .await
+            .map_err(|_| error::PersistenceError::CommitTransaction)
+    }
+
+    async fn rollback(self) -> error::Result<()> {
+        self.0
+            .rollback()
+            .await
+            .map_err(|_| error::PersistenceError::RollbackTransaction)
+    }
 }

src/lib.rs

@@ -1,3 +1,6 @@
+#![deny(clippy::all)]
+#![cfg_attr(feature = "nightly", feature(generic_associated_types))]
+
 #[cfg(feature = "async")]
 #[macro_use]
 extern crate async_trait;

src/r2d2_postgres.rs

@@ -1,17 +1,21 @@
 use crate::error;
+#[cfg(feature = "nightly")]
+use crate::syn::TransactionClient;
 use crate::syn::{ConnectionClient, PersistencePool};
 
 pub use r2d2::{Pool, PooledConnection};
 pub use r2d2_postgres::postgres;
 pub use r2d2_postgres::PostgresConnectionManager as Manager;
 
+pub type InnerConn<M> = PooledConnection<M>;
+pub type InnerTrx<'t> = postgres::Transaction<'t>;
+
 pub type NoTlsManager = Manager<postgres::NoTls>;
 pub type NoTlsPersistence<'p> = Persistence<'p, NoTlsManager>;
-pub type NoTlsConnection<'p> = Connection<NoTlsManager>;
+pub type NoTlsConnection = Connection<NoTlsManager>;
+pub type NoTlsInnerConn = InnerConn<NoTlsManager>;
 pub type NoTlsPool = Pool<NoTlsManager>;
 
-pub type InnerConn<M> = PooledConnection<M>;
-
 pub fn new<M>(pool: &Pool<M>) -> Persistence<M>
 where
     M: r2d2::ManageConnection,
@@ -20,14 +24,12 @@ where
 }
 
 #[derive(Clone)]
-pub struct Persistence<'p, M: r2d2::ManageConnection>(&'p Pool<M>);
-
-#[async_trait]
-impl<'p, M> PersistencePool for Persistence<'p, M>
+pub struct Persistence<'p, M>(&'p Pool<M>)
 where
-    M: r2d2::ManageConnection + Send + Sync,
-{
-    type Conn = Connection<M>;
+    M: r2d2::ManageConnection;
+
+impl<'p> PersistencePool for NoTlsPersistence<'p> {
+    type Conn = NoTlsConnection;
 
     fn get_connection(&self) -> error::Result<Self::Conn> {
         self.0
@@ -37,15 +39,61 @@ where
     }
 }
 
-pub struct Connection<M: r2d2::ManageConnection>(InnerConn<M>);
-
-impl<M> ConnectionClient for Connection<M>
+pub struct Connection<M>(InnerConn<M>)
 where
-    M: r2d2::ManageConnection,
-{
-    type InnerConn = InnerConn<M>;
+    M: r2d2::ManageConnection;
+
+impl ConnectionClient for NoTlsConnection {
+    type InnerConn = NoTlsInnerConn;
+
+    #[cfg(feature = "nightly")]
+    type Trx<'t> = Transaction<'t>;
 
     fn inner(&mut self) -> &mut Self::InnerConn {
         &mut self.0
     }
+
+    #[cfg(feature = "nightly")]
+    fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>> {
+        self.0
+            .transaction()
+            .map_err(|_| error::PersistenceError::UpgradeToTransaction)
+            .map(Transaction)
+    }
+}
+
+#[cfg(feature = "nightly")]
+pub struct Transaction<'me>(InnerTrx<'me>);
+
+#[cfg(feature = "nightly")]
+impl<'me> ConnectionClient for Transaction<'me> {
+    type InnerConn = InnerTrx<'me>;
+
+    type Trx<'t> = Transaction<'t>;
+
+    fn inner(&mut self) -> &mut Self::InnerConn {
+        &mut self.0
+    }
+
+    fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>> {
+        self.0
+            .transaction()
+            .map_err(|_| error::PersistenceError::UpgradeToTransaction)
+            .map(Transaction)
+    }
+}
+
+#[cfg(feature = "nightly")]
+impl TransactionClient for Transaction<'_> {
+    fn commit(self) -> error::Result<()> {
+        self.0
+            .commit()
+            .map_err(|_| error::PersistenceError::CommitTransaction)
+    }
+
+    fn rollback(self) -> error::Result<()> {
+        self.0
+            .rollback()
+            .map_err(|_| error::PersistenceError::RollbackTransaction)
+    }
 }

src/syn.rs

@@ -9,5 +9,18 @@ pub trait PersistencePool {
 pub trait ConnectionClient {
     type InnerConn;
 
+    #[cfg(feature = "nightly")]
+    type Trx<'t>: TransactionClient;
+
     fn inner(&mut self) -> &mut Self::InnerConn;
+
+    #[cfg(feature = "nightly")]
+    fn start_transaction(&mut self) -> error::Result<Self::Trx<'_>>;
+}
+
+#[cfg(feature = "nightly")]
+pub trait TransactionClient: ConnectionClient {
+    fn commit(self) -> error::Result<()>;
+
+    fn rollback(self) -> error::Result<()>;
 }