# MyVC (MySQL Version Control)

Utilities to ease the maintenance of MySQL or MariaDB database versioning using
a Git repository.

This project is just to bring an idea to life and is still in an early stage of
development, so it may not be fully functional.

Any help is welcomed! Feel free to contribute.

## Requirements

* Node.js <= 12.0
* Git
* Docker (Only to setup a local server)

## Installation

It's recommended to install the package globally.

```text
# npm install -g myvc
$ myvc [command]
```

You can also install locally and use the *npx* command to execute it.

```text
$ npm install myvc
$ npx myvc [command]
```

## How to use

Execute *myvc* with the desired command.

```text
$ myvc [-w|--workspace] [-e|--env] [-h|--help] command
```

The default workspace directory is the current working directory and unless 
otherwise indicated, the default environment is *local*.

Commands for database versioning:

 * **init**: Initialize an empty workspace.
 * **pull**: Export database routines into workspace.
 * **push**: Apply changes into database.

Commands for local server management:

 * **dump**: Export database structure and fixtures from *production*.
 * **run**: Build and starts local database server container.
 * **start**: Start local database server container.

Each command can have its own specific commandline options.

## Basic information

First of all you have to initalize your workspace.

```text
$ myvc init
```

Now you can configure MyVC using *myvc.config.yml* file, located at the root of
your workspace. This file should include the project codename and schemas/tables
wich are exported when you use *pull* or *dump* commands.

### Environments

Create database connection configuration for each environment at *remotes*
folder using standard MySQL *ini* configuration files. The predefined
environment names are *production* and *test*.

```text
remotes/[environment].ini
```

### Dumps

Structure and fixture dumps will be created into hidden file *dump/.dump.sql*.
You can also create your local fixture and structure files.

* *dump/structure.sql*
* *dump/fixtures.sql*

### Routines

Routines should be placed inside *routines* folder. All objects that have
PL/SQL code are considered routines. It includes events, functions, procedures,
triggers and views with the following structure.

```text
  routines
  `- schema
     |- events
     |  `- eventName.sql
     |- functions
     |  `- functionName.sql
     |- procedures
     |  `- procedureName.sql
     |- triggers
     |  `- triggerName.sql
     `- views
        `- viewName.sql
```

### Versions

Versions should be placed inside *versions* folder with the following structure.
Don't place your PL/SQL objects here, use the routines folder!

```text
  versions
  |- 00001-firstVersionCodeName
  |  |- 00-firstExecutedScript.sql
  |  |- 01-secondScript.sql
  |  `- 99-lastScript.sql
  `- 00002-secondVersion
     |- 00-firstExecutedScript.sql
     `- 00-sameNumbers.sql
```

### Local server

The local server will be created as a MariaDB Docker container using the base
dump created with the *dump* command plus pushing local versions and changed
routines.

## Why

The main reason for starting this project it's because there are no fully free 
and opensource migration tools available that allow versioning database routines
with an standard CVS system as if they were normal application code.

Also, the existing tools are too complex and require too much knowledge to start
a small project.

## Todo

Improve the pull command to, instead of completely overwriting the routines
directory, merge the database changes with the local SQL files. It is possible
using a library that allows to manipulate git repositories (nodegit) and running
the following steps:

1. Save the current HEAD.
2. Check out to the last database push commit (saved in versioning tables).
3. Create and checkout to a new branch.
4. Export database routines.
5. Commit the new changes.
5. Checkout to the original HEAD.
6. Merge the new branch into.
7. Let the user deal with merge conflicts.

Furthermore, migrate all possible tools and code from shell scripts to native
Javascript, dealing with dependencies and compatibility issues between various
OS that this may cause.

## Built With

* [Git](https://git-scm.com/)
* [nodejs](https://nodejs.org/)
* [docker](https://www.docker.com/)