# PostgreSQL Docker Container

A Dockerized PostgreSQL database setup using Alpine Linux, designed for easy deployment and customization.

## Overview

This repository contains the necessary files to build a PostgreSQL Docker container. The container is pre-configured to initialize databases, users, and execute custom scripts on startup. It uses the lightweight Alpine Linux base image for efficiency.

## Prerequisites

- Docker installed on your system
- Access to the base image `git.esculta.es/aesculta/alpine-base` (or modify the `Dockerfile` to use a public base image)

## Getting Started

### Run the container

```bash
docker run -d \
  --name my-postgres \
  -e POSTGRES_PASSWORD=mysecretpassword \
  -e POSTGRES_USER=customuser \
  -e POSTGRES_DB=mydatabase \
  -v postgres_data:/var/lib/postgresql/data \
  -p 5432:5432 \
  git.esculta.es/aesculta/postgres:latest
```

### Environment Variables

Configure the container using these environment variables:

* **POSTGRES_USER** (default: postgres): Database superuser name

* **POSTGRES_DB** (default: same as POSTGRES_USER): Default database name

* **POSTGRES_PASSWORD**: Password for the superuser (recommended for production)

**Warning:** If no password is set, the container will use trust authentication (insecure).

### Initialization Scripts

Place SQL or Shell scripts in `/docker-entrypoint-initdb.d` to execute them during initialization:

1. Create a files directory

2. Add your scripts:

* .sql files will be executed by psql

* .sh files will be sourced in the shell

* Rebuild the Docker image

Example structure:
```bash
/files
  /docker-entrypoint-initdb.d
    init.sql
    setup.sh
```

### Persistent Data

Data is stored in the Docker volume mounted at /var/lib/postgresql/data. To persist data between container restarts:

```bash
# Create a named volume
docker volume create postgres_data

# Use the volume in your container
docker run ... -v postgres_data:/var/lib/postgresql/data ...
```
### Security Considerations

1. Always set POSTGRES_PASSWORD in production environments

2. The default configuration allows remote connections (`host all all 0.0.0.0/0`)

3. For production use:

* Consider customizing pg_hba.conf

* Use proper TLS certificates

* Restrict network access

### Exposing the Service
The container exposes PostgreSQL on port 5432. Map to host port using:

```bash
-p [HOST_PORT]:5432
```


### Build the Docker Image

```bash
docker build -t my-postgres .