update migrate Transaction and AsyncTransaction (#393)

execute functions, to avoid double iteration.

Author: jxs

refinery_core/src/drivers/config.rs

@@ -18,7 +18,10 @@ use std::convert::Infallible;
 impl Transaction for Config {
     type Error = Infallible;
 
-    fn execute(&mut self, _queries: &[&str]) -> Result<usize, Self::Error> {
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        _queries: T,
+    ) -> Result<usize, Self::Error> {
         Ok(0)
     }
 }
@@ -33,7 +36,10 @@ impl Query<Vec<Migration>> for Config {
 impl AsyncTransaction for Config {
     type Error = Infallible;
 
-    async fn execute(&mut self, _queries: &[&str]) -> Result<usize, Self::Error> {
+    async fn execute<'a, T: Iterator<Item = &'a str> + Send>(
+        &mut self,
+        _queries: T,
+    ) -> Result<usize, Self::Error> {
         Ok(0)
     }
 }

refinery_core/src/drivers/mysql.rs

@@ -43,10 +43,13 @@ fn query_applied_migrations(
 impl Transaction for Conn {
     type Error = MError;
 
-    fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let mut transaction = self.start_transaction(get_tx_opts())?;
         let mut count = 0;
-        for query in queries.iter() {
+        for query in queries {
             transaction.query_iter(query)?;
             count += 1;
         }
@@ -58,11 +61,14 @@ impl Transaction for Conn {
 impl Transaction for PooledConn {
     type Error = MError;
 
-    fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let mut transaction = self.start_transaction(get_tx_opts())?;
         let mut count = 0;
 
-        for query in queries.iter() {
+        for query in queries {
             transaction.query_iter(query)?;
             count += 1;
         }

refinery_core/src/drivers/mysql_async.rs

@@ -40,15 +40,18 @@ async fn query_applied_migrations<'a>(
 impl AsyncTransaction for Pool {
     type Error = MError;
 
-    async fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    async fn execute<'a, T: Iterator<Item = &'a str> + Send>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let mut conn = self.get_conn().await?;
         let mut options = TxOpts::new();
         options.with_isolation_level(Some(IsolationLevel::ReadCommitted));
 
         let mut transaction = conn.start_transaction(options).await?;
         let mut count = 0;
         for query in queries {
-            transaction.query_drop(*query).await?;
+            transaction.query_drop(query).await?;
             count += 1;
         }
         transaction.commit().await?;

refinery_core/src/drivers/postgres.rs

@@ -33,10 +33,13 @@ fn query_applied_migrations(
 impl Transaction for PgClient {
     type Error = PgError;
 
-    fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let mut transaction = PgClient::transaction(self)?;
         let mut count = 0;
-        for query in queries.iter() {
+        for query in queries {
             PgTransaction::batch_execute(&mut transaction, query)?;
             count += 1;
         }

refinery_core/src/drivers/rusqlite.rs

@@ -32,10 +32,13 @@ fn query_applied_migrations(
 
 impl Transaction for RqlConnection {
     type Error = RqlError;
-    fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let transaction = self.transaction()?;
         let mut count = 0;
-        for query in queries.iter() {
+        for query in queries {
             transaction.execute_batch(query)?;
             count += 1;
         }

refinery_core/src/drivers/tiberius.rs

@@ -47,13 +47,16 @@ where
 {
     type Error = Error;
 
-    async fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    async fn execute<'a, T: Iterator<Item = &'a str> + Send>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         // Tiberius doesn't support transactions, see https://github.com/prisma/tiberius/issues/28
         self.simple_query("BEGIN TRAN T1;").await?;
         let mut count = 0;
         for query in queries {
             // Drop the returning `QueryStream<'a>` to avoid compiler complaning regarding lifetimes
-            if let Err(err) = self.simple_query(*query).await.map(drop) {
+            if let Err(err) = self.simple_query(query).await.map(drop) {
                 if let Err(err) = self.simple_query("ROLLBACK TRAN T1").await {
                     log::error!("could not ROLLBACK transaction, {}", err);
                 }

refinery_core/src/drivers/tokio_postgres.rs

@@ -35,7 +35,10 @@ async fn query_applied_migrations(
 impl AsyncTransaction for Client {
     type Error = PgError;
 
-    async fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error> {
+    async fn execute<'a, T: Iterator<Item = &'a str> + Send>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error> {
         let transaction = self.transaction().await?;
         let mut count = 0;
         for query in queries {

refinery_core/src/traits/async.rs

@@ -12,7 +12,10 @@ use std::string::ToString;
 pub trait AsyncTransaction {
     type Error: std::error::Error + Send + Sync + 'static;
 
-    async fn execute(&mut self, query: &[&str]) -> Result<usize, Self::Error>;
+    async fn execute<'a, T: Iterator<Item = &'a str> + Send>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error>;
 }
 
 #[async_trait]
@@ -43,10 +46,13 @@ async fn migrate<T: AsyncTransaction>(
         migration.set_applied();
         let update_query = insert_migration_query(&migration, migration_table_name);
         transaction
-            .execute(&[
-                migration.sql().as_ref().expect("sql must be Some!"),
-                &update_query,
-            ])
+            .execute(
+                [
+                    migration.sql().as_ref().expect("sql must be Some!"),
+                    update_query.as_str(),
+                ]
+                .into_iter(),
+            )
             .await
             .migration_err(
                 &format!("error applying migration {migration}"),
@@ -109,10 +115,8 @@ async fn migrate_grouped<T: AsyncTransaction>(
         );
     }
 
-    let refs: Vec<&str> = grouped_migrations.iter().map(AsRef::as_ref).collect();
-
     transaction
-        .execute(refs.as_ref())
+        .execute(grouped_migrations.iter().map(AsRef::as_ref))
         .await
         .migration_err("error applying migrations", None)?;
 
@@ -142,7 +146,7 @@ where
         migration_table_name: &str,
     ) -> Result<Option<Migration>, Error> {
         let mut migrations = self
-            .query(Self::get_last_applied_migration_query(migration_table_name).as_str())
+            .query(Self::get_last_applied_migration_query(migration_table_name).as_ref())
             .await
             .migration_err("error getting last applied migration", None)?;
 
@@ -154,7 +158,7 @@ where
         migration_table_name: &str,
     ) -> Result<Vec<Migration>, Error> {
         let migrations = self
-            .query(Self::get_applied_migrations_query(migration_table_name).as_str())
+            .query(Self::get_applied_migrations_query(migration_table_name).as_ref())
             .await
             .migration_err("error getting applied migrations", None)?;
 
@@ -170,9 +174,11 @@ where
         target: Target,
         migration_table_name: &str,
     ) -> Result<Report, Error> {
-        self.execute(&[&Self::assert_migrations_table_query(migration_table_name)])
-            .await
-            .migration_err("error asserting migrations table", None)?;
+        self.execute(
+            [Self::assert_migrations_table_query(migration_table_name).as_ref()].into_iter(),
+        )
+        .await
+        .migration_err("error asserting migrations table", None)?;
 
         let applied_migrations = self
             .get_applied_migrations(migration_table_name)

refinery_core/src/traits/sync.rs

@@ -8,7 +8,10 @@ use crate::{Error, Migration, Report, Target};
 pub trait Transaction {
     type Error: std::error::Error + Send + Sync + 'static;
 
-    fn execute(&mut self, queries: &[&str]) -> Result<usize, Self::Error>;
+    fn execute<'a, T: Iterator<Item = &'a str>>(
+        &mut self,
+        queries: T,
+    ) -> Result<usize, Self::Error>;
 }
 
 pub trait Query<T>: Transaction {
@@ -66,7 +69,7 @@ pub fn migrate<T: Transaction>(
         }
     };
 
-    let refs: Vec<&str> = migration_batch.iter().map(AsRef::as_ref).collect();
+    let refs = migration_batch.iter().map(AsRef::as_ref);
 
     if batched {
         let migrations_display = applied_migrations
@@ -76,10 +79,10 @@ pub fn migrate<T: Transaction>(
             .join("\n");
         log::info!("going to apply batch migrations in single transaction:\n{migrations_display}");
         transaction
-            .execute(refs.as_ref())
+            .execute(refs)
             .migration_err("error applying migrations", None)?;
     } else {
-        for (i, update) in refs.iter().enumerate() {
+        for (i, update) in refs.enumerate() {
             // first iteration is pair so we know the following even in the iteration index
             // marks the previous (pair) migration as completed.
             let applying_migration = i % 2 == 0;
@@ -91,7 +94,7 @@ pub fn migrate<T: Transaction>(
                 log::debug!("applied migration:  {current_migration} writing state to db.");
             }
             transaction
-                .execute(&[update])
+                .execute([update].into_iter())
                 .migration_err("error applying update", Some(&applied_migrations[0..i / 2]))?;
         }
     }
@@ -119,8 +122,10 @@ where
     fn assert_migrations_table(&mut self, migration_table_name: &str) -> Result<usize, Error> {
         // Needed cause some database vendors like Mssql have a non sql standard way of checking the migrations table,
         // though on this case it's just to be consistent with the async trait `AsyncMigrate`
-        self.execute(&[Self::assert_migrations_table_query(migration_table_name).as_str()])
-            .migration_err("error asserting migrations table", None)
+        self.execute(
+            [Self::assert_migrations_table_query(migration_table_name).as_ref()].into_iter(),
+        )
+        .migration_err("error asserting migrations table", None)
     }
 
     fn get_last_applied_migration(