dh_demo

DreamHanks demo project
git clone git://git.lair.cx/dh_demo
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model_helpers.ts (1296B)

      1 import db from '@/lib/db'
      2 import { Connection, PoolConnection } from 'mysql2/promise'
      3 
      4 type ConnHandler<T> = (conn: Connection) => Promise<T>
      5 
      6 function transactionWrapper<T> (
      7   conn: PoolConnection,
      8   fn: ConnHandler<T>,
      9 ): ConnHandler<T> {
     10   return async (conn: Connection) => {
     11     try {
     12       await conn.beginTransaction()
     13       const result = await fn(conn)
     14       await conn.commit()
     15       return result
     16     } finally {
     17       await conn.rollback()
     18     }
     19   }
     20 }
     21 
     22 export async function withConnection<T> (
     23   fn: ConnHandler<T>,
     24   withoutTransaction?: boolean,
     25 ): Promise<T> {
     26   const conn = await db.getConnection()
     27 
     28   const handler = withoutTransaction
     29     ? fn
     30     : transactionWrapper(conn, fn)
     31 
     32   try {
     33     return await handler(conn)
     34   } finally {
     35     conn.release()
     36   }
     37 }
     38 
     39 export type ModelBehaviour<TArgs, TResult> =
     40   ((conn: Connection, args: TArgs) => Promise<TResult>) &
     41   ((args: TArgs) => Promise<TResult>)
     42 
     43 export function modelBehaviour<TArgs, TResult> (
     44   fn: (conn: Connection, args: TArgs) => Promise<TResult>,
     45 ): ModelBehaviour<TArgs, TResult> {
     46   return (connOrArgs: Connection | TArgs, args?: TArgs): Promise<TResult> => {
     47     if (args != null) {
     48       return fn(connOrArgs as Connection, args)
     49     }
     50     return withConnection((conn) => fn(conn, connOrArgs as TArgs))
     51   }
     52 }