create beginPrepared function

.github/workflows/test.yml

@@ -35,6 +35,7 @@ jobs:
           sudo apt-get -y install "postgresql-${{ matrix.postgres }}"
           sudo cp ./tests/pg_hba.conf /etc/postgresql/${{ matrix.postgres }}/main/pg_hba.conf
           sudo sed -i 's/.*wal_level.*/wal_level = logical/' /etc/postgresql/${{ matrix.postgres }}/main/postgresql.conf
+          sudo sed -i 's/.*max_prepared_transactions.*/max_prepared_transactions = 100/' /etc/postgresql/${{ matrix.postgres }}/main/postgresql.conf
           sudo sed -i 's/.*ssl = .*/ssl = on/' /etc/postgresql/${{ matrix.postgres }}/main/postgresql.conf
           openssl req -new -x509 -nodes -days 365 -text -subj "/CN=localhost" -extensions v3_req -config <(cat /etc/ssl/openssl.cnf <(printf "\n[v3_req]\nbasicConstraints=critical,CA:TRUE\nkeyUsage=nonRepudiation,digitalSignature,keyEncipherment\nsubjectAltName=DNS:localhost")) -keyout server.key -out server.crt
           sudo cp server.key /etc/postgresql/${{ matrix.postgres }}/main/server.key

README.md

@@ -637,6 +637,26 @@ sql.begin('read write', async sql => {
 })
 ```
 
+
+#### PREPARE `await sql.prepare([name]) -> fn()`
+
+Indicates that the transactions should be prepared using the `PREPARED TRANASCTION [NAME]` statement
+instead of being committed.
+
+```js
+sql.begin('read write', async sql => {
+  const [user] = await sql`
+    insert into users (
+      name
+    ) values (
+      'Murray'
+    )
+  `
+
+  await sql.prepare('tx1')
+})
+```
+
 Do note that you can often achieve the same result using [`WITH` queries (Common Table Expressions)](https://www.postgresql.org/docs/current/queries-with.html) instead of using transactions.
 
 ## Data Transformation

cjs/src/index.js

@@ -235,6 +235,7 @@ function Postgres(a, b) {
     const queries = Queue()
     let savepoints = 0
       , connection
+    let transactionId = null
 
     try {
       await sql.unsafe('begin ' + options.replace(/[^a-z ]/ig, ''), [], { onexecute }).execute()
@@ -246,6 +247,7 @@ function Postgres(a, b) {
     async function scope(c, fn, name) {
       const sql = Sql(handler)
       sql.savepoint = savepoint
+      sql.prepare = prepare
       let uncaughtError
         , result
 
@@ -266,7 +268,11 @@ function Postgres(a, b) {
         throw e instanceof PostgresError && e.code === '25P02' && uncaughtError || e
       }
 
-      !name && await sql`commit`
+      if (transactionId) {
+        !name && await sql.unsafe(`prepare transaction '${transactionId}'`)
+      }else{
+        !name && await sql`commit`
+      }
       return result
 
       function savepoint(name, fn) {
@@ -285,6 +291,9 @@ function Postgres(a, b) {
       }
     }
 
+    async function prepare(name) {
+      transactionId = name
+    }
     function onexecute(c) {
       connection = c
       move(c, reserved)
@@ -294,6 +303,7 @@ function Postgres(a, b) {
     }
   }
 
+
   function move(c, queue) {
     c.queue.remove(c)
     queue.push(c)

cjs/tests/index.js

@@ -238,6 +238,19 @@ t('Savepoint returns Result', async() => {
   return [1, result[0].x]
 })
 
+t('Prepared transaction', async() => {
+  await sql`create table test (a int)`
+
+  await sql.begin(async sql => {
+    await sql`insert into test values(1)`
+    await sql.prepare('tx1')
+  })
+
+  await sql.unsafe("commit prepared 'tx1'")
+
+  return ['1', (await sql`select count(1) from test`)[0].count, await sql`drop table test`]
+})
+
 t('Transaction requests are executed implicitly', async() => {
   const sql = postgres({ debug: true, idle_timeout: 1, fetch_types: false })
   return [

deno/README.md

@@ -633,6 +633,26 @@ sql.begin('read write', async sql => {
 })
 ```
 
+
+#### PREPARE `await sql.prepare([name]) -> fn()`
+
+Indicates that the transactions should be prepared using the `PREPARED TRANASCTION [NAME]` statement
+instead of being committed.
+
+```js
+sql.begin('read write', async sql => {
+  const [user] = await sql`
+    insert into users (
+      name
+    ) values (
+      'Murray'
+    )
+  `
+
+  await sql.prepare('tx1')
+})
+```
+
 Do note that you can often achieve the same result using [`WITH` queries (Common Table Expressions)](https://www.postgresql.org/docs/current/queries-with.html) instead of using transactions.
 
 ## Data Transformation

deno/src/index.js

@@ -236,6 +236,7 @@ function Postgres(a, b) {
     const queries = Queue()
     let savepoints = 0
       , connection
+    let transactionId = null
 
     try {
       await sql.unsafe('begin ' + options.replace(/[^a-z ]/ig, ''), [], { onexecute }).execute()
@@ -247,6 +248,7 @@ function Postgres(a, b) {
     async function scope(c, fn, name) {
       const sql = Sql(handler)
       sql.savepoint = savepoint
+      sql.prepare = prepare
       let uncaughtError
         , result
 
@@ -267,7 +269,11 @@ function Postgres(a, b) {
         throw e instanceof PostgresError && e.code === '25P02' && uncaughtError || e
       }
 
-      !name && await sql`commit`
+      if (transactionId) {
+        !name && await sql.unsafe(`prepare transaction '${transactionId}'`)
+      }else{
+        !name && await sql`commit`
+      }
       return result
 
       function savepoint(name, fn) {
@@ -286,6 +292,9 @@ function Postgres(a, b) {
       }
     }
 
+    async function prepare(name) {
+      transactionId = name
+    }
     function onexecute(c) {
       connection = c
       move(c, reserved)
@@ -295,6 +304,7 @@ function Postgres(a, b) {
     }
   }
 
+
   function move(c, queue) {
     c.queue.remove(c)
     queue.push(c)

deno/tests/index.js

@@ -240,6 +240,19 @@ t('Savepoint returns Result', async() => {
   return [1, result[0].x]
 })
 
+t('Prepared transaction', async() => {
+  await sql`create table test (a int)`
+
+  await sql.begin(async sql => {
+    await sql`insert into test values(1)`
+    await sql.prepare('tx1')
+  })
+
+  await sql.unsafe("commit prepared 'tx1'")
+
+  return ['1', (await sql`select count(1) from test`)[0].count, await sql`drop table test`]
+})
+
 t('Transaction requests are executed implicitly', async() => {
   const sql = postgres({ debug: true, idle_timeout: 1, fetch_types: false })
   return [

deno/types/index.d.ts

@@ -698,6 +698,8 @@ declare namespace postgres {
   interface TransactionSql<TTypes extends Record<string, unknown> = {}> extends Sql<TTypes> {
     savepoint<T>(cb: (sql: TransactionSql<TTypes>) => T | Promise<T>): Promise<UnwrapPromiseArray<T>>;
     savepoint<T>(name: string, cb: (sql: TransactionSql<TTypes>) => T | Promise<T>): Promise<UnwrapPromiseArray<T>>;
+
+    prepare<T>(name: string): Promise<UnwrapPromiseArray<T>>;
   }
 }
 

src/index.js

@@ -235,6 +235,7 @@ function Postgres(a, b) {
     const queries = Queue()
     let savepoints = 0
       , connection
+    let transactionId = null
 
     try {
       await sql.unsafe('begin ' + options.replace(/[^a-z ]/ig, ''), [], { onexecute }).execute()
@@ -246,6 +247,7 @@ function Postgres(a, b) {
     async function scope(c, fn, name) {
       const sql = Sql(handler)
       sql.savepoint = savepoint
+      sql.prepare = prepare
       let uncaughtError
         , result
 
@@ -266,7 +268,11 @@ function Postgres(a, b) {
         throw e instanceof PostgresError && e.code === '25P02' && uncaughtError || e
       }
 
-      !name && await sql`commit`
+      if (transactionId) {
+        !name && await sql.unsafe(`prepare transaction '${transactionId}'`)
+      }else{
+        !name && await sql`commit`
+      }
       return result
 
       function savepoint(name, fn) {
@@ -285,6 +291,9 @@ function Postgres(a, b) {
       }
     }
 
+    async function prepare(name) {
+      transactionId = name
+    }
     function onexecute(c) {
       connection = c
       move(c, reserved)
@@ -294,6 +303,7 @@ function Postgres(a, b) {
     }
   }
 
+
   function move(c, queue) {
     c.queue.remove(c)
     queue.push(c)

tests/bootstrap.js

@@ -14,7 +14,6 @@ exec('createdb', ['postgres_js_test'])
 exec('psql', ['-c', 'grant all on database postgres_js_test to postgres_js_test'])
 exec('psql', ['-c', 'alter database postgres_js_test owner to postgres_js_test'])
 
-
 export function exec(cmd, args) {
   const { stderr } = spawnSync(cmd, args, { stdio: 'pipe', encoding: 'utf8' })
   if (stderr && !stderr.includes('already exists') && !stderr.includes('does not exist'))

tests/index.js

@@ -238,6 +238,19 @@ t('Savepoint returns Result', async() => {
   return [1, result[0].x]
 })
 
+t('Prepared transaction', async() => {
+  await sql`create table test (a int)`
+
+  await sql.begin(async sql => {
+    await sql`insert into test values(1)`
+    await sql.prepare('tx1')
+  })
+
+  await sql.unsafe("commit prepared 'tx1'")
+
+  return ['1', (await sql`select count(1) from test`)[0].count, await sql`drop table test`]
+})
+
 t('Transaction requests are executed implicitly', async() => {
   const sql = postgres({ debug: true, idle_timeout: 1, fetch_types: false })
   return [

types/index.d.ts

@@ -696,6 +696,8 @@ declare namespace postgres {
   interface TransactionSql<TTypes extends Record<string, unknown> = {}> extends Sql<TTypes> {
     savepoint<T>(cb: (sql: TransactionSql<TTypes>) => T | Promise<T>): Promise<UnwrapPromiseArray<T>>;
     savepoint<T>(name: string, cb: (sql: TransactionSql<TTypes>) => T | Promise<T>): Promise<UnwrapPromiseArray<T>>;
+
+    prepare<T>(name: string): Promise<UnwrapPromiseArray<T>>;
   }
 }