From ee5bd41a372d32fb0fa53a394ad7343123aec382 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Julian=20T=C3=B6lle?= <julian.toelle97@gmail.com>
Date: Sat, 11 Jun 2022 18:47:04 +0200
Subject: [PATCH] feat(api): configurable max pool connections

This should help with failing health checks while the crawler is running.

Quick math: 10 users, 30 songs each, each song requires at least 3
queries => 900 db queries every minute.

With the default of 10 pool connections, this blocks all available db
bandwidth for some time and causes slow UI and failing healthchecks.
---
 README.md                                | 1 +
 charts/listory/templates/deployment.yaml | 2 ++
 charts/listory/values.yaml               | 3 +++
 src/config/config.module.ts              | 1 +
 src/database/database.module.ts          | 5 +++++
 5 files changed, 12 insertions(+)

diff --git a/README.md b/README.md
index 8e6ec6d..334ef14 100644
--- a/README.md
+++ b/README.md
@@ -41,6 +41,7 @@ All configuration must be set as environment variables. Default values are added
 - `DB_USERNAME`: _Required_, Database username
 - `DB_PASSWORD`: _Required_, Database password
 - `DB_DATABASE`: _Required_, Database database
+- `DB_POOL_MAX`: **50**, max concurrent database connections
 
 #### Sentry
 
diff --git a/charts/listory/templates/deployment.yaml b/charts/listory/templates/deployment.yaml
index 695ceae..9835b33 100644
--- a/charts/listory/templates/deployment.yaml
+++ b/charts/listory/templates/deployment.yaml
@@ -37,6 +37,8 @@ spec:
                   key: postgres-password
             - name: DB_DATABASE
               value: {{ .Values.externalDatabase.database }}
+            - name: DB_POOL_MAX
+              value: "{{ .Values.database.poolMax }}"
             - name: JWT_SECRET
               valueFrom:
                 secretKeyRef:
diff --git a/charts/listory/values.yaml b/charts/listory/values.yaml
index fe16650..89c05e1 100644
--- a/charts/listory/values.yaml
+++ b/charts/listory/values.yaml
@@ -75,6 +75,9 @@ externalDatabase:
   password:
   database:
 
+database:
+  poolMax: 50
+
 spotify:
   clientId:
   clientSecret:
diff --git a/src/config/config.module.ts b/src/config/config.module.ts
index 69a9b40..20cb1d6 100644
--- a/src/config/config.module.ts
+++ b/src/config/config.module.ts
@@ -36,6 +36,7 @@ import { ConfigModule as NestConfigModule } from "@nestjs/config";
         DB_USERNAME: Joi.string().required(),
         DB_PASSWORD: Joi.string().required(),
         DB_DATABASE: Joi.string().required(),
+        DB_POOL_MAX: Joi.number().default(50),
 
         // Sentry (Optional)
         SENTRY_ENABLED: Joi.boolean().default(false),
diff --git a/src/database/database.module.ts b/src/database/database.module.ts
index 0ed79a6..06ac587 100644
--- a/src/database/database.module.ts
+++ b/src/database/database.module.ts
@@ -20,6 +20,11 @@ export const DatabaseModule = TypeOrmModule.forRootAsync({
     migrationsRun: true,
     migrations: [join(__dirname, "migrations", "*.{ts,js}")],
 
+    // PG Driver Options
+    extra: {
+      max: config.get<number>("DB_POOL_MAX"),
+    },
+
     // Debug/Development Options
     //
     // logging: true,