From a1e6284a169696cbe7baf255866565d0a9e0b7f5 Mon Sep 17 00:00:00 2001
From: Dmitry Anderson <4nd3r5z0n@gmail.com>
Date: Fri, 25 Oct 2024 20:10:48 +0200
Subject: [PATCH] drop DB functionality added

---
 config.ts        |  50 +++++++++++-----------
 repo/setup_db.ts | 105 +++++++++++++++++++++++++++++------------------
 2 files changed, 89 insertions(+), 66 deletions(-)

diff --git a/config.ts b/config.ts
index 4c31b26..d743f04 100644
--- a/config.ts
+++ b/config.ts
@@ -13,30 +13,30 @@ export const DEFAULT_DB_PORT = 5432
 export const DEFAULT_DB_TLS  = false
 
 export const loadConfig = (): CompiledConfig => {
-    const cfg = getConfig()
-    const pgPoolCfg: PoolConfig = {
-        host: cfg.db_host     || DEFAULT_DB_HOST,
-        user: cfg.db_user     || DEFAULT_DB_USER,
-        database: cfg.db_name || DEFAULT_DB_NAME,
-        port: cfg.db_port     || DEFAULT_DB_PORT,
-        ssl: cfg.db_tls       || DEFAULT_DB_TLS,
-        password: cfg.db_password,
-    }
-    const botCfg: BotConfig = {
-        mode: BotMode.normal,
-        bot_token: cfg.bot_token,
-        chat_id: MIC_CHAT_ID,
-        admin_ids: [
-            MR_ANDERSON_ID,
-        ]
-    }
-    return {
-        pgPoolCfg,       botCfg,
-        migrationCfg: {
-            dropDb:          cfg.drop_db,
-            applyMigrations: cfg.apply_migrations,
-            migrationsPath:  import.meta.dirname ?
-                path.join(import.meta.dirname, 'migrations') : '/app/migrations',
-        }
+  const cfg = getConfig()
+  const pgPoolCfg: PoolConfig = {
+    host: cfg.db_host     || DEFAULT_DB_HOST,
+    user: cfg.db_user     || DEFAULT_DB_USER,
+    database: cfg.db_name || DEFAULT_DB_NAME,
+    port: cfg.db_port     || DEFAULT_DB_PORT,
+    ssl: cfg.db_tls       || DEFAULT_DB_TLS,
+    password: cfg.db_password,
+  }
+  const botCfg: BotConfig = {
+    mode: BotMode.normal,
+    bot_token: cfg.bot_token,
+    chat_id: MIC_CHAT_ID,
+    admin_ids: [
+      MR_ANDERSON_ID,
+    ]
+  }
+  return {
+    pgPoolCfg, botCfg,
+    migrationCfg: {
+      dropDb:          cfg.drop_db,
+      applyMigrations: cfg.apply_migrations,
+      migrationsPath:  import.meta.dirname ?
+        path.join(import.meta.dirname, 'migrations') : '/app/migrations',
     }
+  }
 }
diff --git a/repo/setup_db.ts b/repo/setup_db.ts
index 7cb236d..e27e5b6 100644
--- a/repo/setup_db.ts
+++ b/repo/setup_db.ts
@@ -10,54 +10,77 @@ import pg from "npm:pg";
 import { Database } from "./scheme.ts"
 import { CompiledConfig } from "../cfg/config.ts";
 
+
+export const dropDb = async (migrator: Migrator, downLimit?: number) => {
+  console.log(`droping the DB`)
+  let downCounter: number = 0 // to prevent infinite loop
+  while (true) {
+    if (downLimit && downCounter === downLimit) return
+    const { results } = await migrator.migrateDown()
+    if (!results) continue
+
+    for (const { status, migrationName } of results) {
+      if (status === "Error" || status === "NotExecuted") {
+        return
+      }
+      console.log(`down migration "${migrationName}" was executed successfully`)
+    }
+    downCounter++
+  }
+}
+
+
 export type SetupDbOutput = {
     pool: pg.Pool,
     db: Kysely<Database>,
 }
 export const setupDB = async (cfg: CompiledConfig): Promise<SetupDbOutput> => {
-    console.log("creating db instance: ", cfg.pgPoolCfg)
-    const pool = new pg.Pool(cfg.pgPoolCfg)
-    const dialect = new PostgresDialect({ pool })
-    const db = new Kysely<Database>({ dialect })
+  console.log("creating db instance: ", cfg.pgPoolCfg)
+  const pool = new pg.Pool(cfg.pgPoolCfg)
+  const dialect = new PostgresDialect({ pool })
+  const db = new Kysely<Database>({ dialect })
 
-    if (cfg.migrationCfg?.applyMigrations) {
-        console.log("applying db migrations", cfg.migrationCfg.migrationsPath)
-        const migrator = new Migrator({
-            db,
-            provider: new FileMigrationProvider({
-                fs: {
-                    readdir(path) {
-                        return Promise.resolve(
-                            [...Deno.readDirSync(path)].map((file) => file.name)
-                        )
-                    },
-                },
-                path: {
-                    join(...path) {
-                        return path.join('/')
-                    },
-                },
-                migrationFolder: cfg.migrationCfg.migrationsPath,
-            }),
-            allowUnorderedMigrations: true
-        })
+  if (cfg.migrationCfg?.applyMigrations) {
+    console.log("applying db migrations", cfg.migrationCfg.migrationsPath)
+    const migrator = new Migrator({
+      db,
+      provider: new FileMigrationProvider({
+        fs: {
+          readdir(path) {
+            return Promise.resolve(
+              [...Deno.readDirSync(path)].map((file) => file.name)
+            )
+          },
+        },
+        path: {
+          join(...path) {
+            return path.join('/')
+          },
+        },
+        migrationFolder: cfg.migrationCfg.migrationsPath,
+      }),
+      allowUnorderedMigrations: true
+    })
 
-        const { error, results } = await migrator.migrateToLatest()
-
-        results?.forEach((it) => {
-          if (it.status === 'Success') {
-            console.log(`migration "${it.migrationName}" was executed successfully`)
-          } else if (it.status === 'Error') {
-            console.error(`failed to execute migration "${it.migrationName}"`)
-          }
-        })
-      
-        if (error) {
-          console.error('failed to migrate')
-          console.error(error)
-          throw error
-        }
+    if (cfg.migrationCfg.dropDb) {
+      await dropDb(migrator, 100)
     }
+    const { error, results } = await migrator.migrateToLatest()
 
-    return { pool, db }
+    results?.forEach((it) => {
+      if (it.status === 'Success') {
+        console.log(`migration "${it.migrationName}" was executed successfully`)
+      } else if (it.status === 'Error') {
+        console.error(`failed to execute migration "${it.migrationName}"`)
+      }
+    })
+  
+    if (error) {
+      console.error('failed to migrate')
+      console.error(error)
+      throw error
+    }
+  }
+
+  return { pool, db }
 }