kustomize-generators

# Kustomize Generators

Master ConfigMap and Secret generation using Kustomize generators for managing application configuration, credentials, and environment-specific settings without manual YAML creation.

## Overview

Kustomize generators automatically create ConfigMaps and Secrets from literals, files, and environment files. Generated resources include content hashes in their names, enabling automatic rollouts when configuration changes.

## ConfigMap Generator Basics

### Literal Values

```yaml
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

configMapGenerator:
  - name: app-config
    literals:
      - DATABASE_URL=postgresql://localhost:5432/mydb
      - LOG_LEVEL=info
      - CACHE_ENABLED=true
      - MAX_CONNECTIONS=100
      - TIMEOUT_SECONDS=30
```

Generated ConfigMap:

```yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: app-config-8g2h5m9k7t
data:
  DATABASE_URL: postgresql://localhost:5432/mydb
  LOG_LEVEL: info
  CACHE_ENABLED: "true"
  MAX_CONNECTIONS: "100"
  TIMEOUT_SECONDS: "30"
```

### File-Based Generation

```yaml
# kustomization.yaml
configMapGenerator:
  - name: app-config
    files:
      - application.properties
      - config/database.conf
      - config/logging.yml
```

With files:

```properties
# application.properties
server.port=8080
server.host=0.0.0.0
app.name=MyApplication
app.version=1.0.0
```

```conf
# config/database.conf
max_connections = 100
shared_buffers = 256MB
effective_cache_size = 1GB
```

```yaml
# config/logging.yml
level: info
format: json
outputs:
  - stdout
  - file: /var/log/app.log
```

### Named Files

```yaml
configMapGenerator:
  - name: app-config
    files:
      - config.properties=application.properties
      - db.conf=config/database.conf
      - log.yml=config/logging.yml
```

Generated ConfigMap:

```yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: app-config-9m4k8h2f6d
data:
  config.properties: |
    server.port=8080
    server.host=0.0.0.0
    app.na