# Pica - Backend for Megpie budgeting app

... some description

### Prerequisites

- fcgi
- nlohmann_json
- mariadb-client
- argon2


### Building

```
$ git clone https://git.macaw.me/blue/pica
$ cd pica
$ mkdir build
$ cd build
$ cmake ..
$ cmake --build .
```

### Usage

#### Webserver
First you need a webserver. In this example I'm going to use apache.

Install apache (apache2, httpd) from your package manager.

Create a file like this in apache config dir (in my case it's `/etc/httpd/conf/extra/fcgi-pica.conf`)
```
<Location /pica>
    <IfModule mod_headers.c>
        Header set Access-Control-Allow-Origin "*"
        Header set Access-Control-Allow-Headers: "*"
    </IfModule>

    ProxyPass "unix:/run/pica/pica.sock|fcgi://localhost"
    ProxyPassReverse "http://localhost"
</Location>
```

Incude this file from apache config file (in my case it's `/etc/httpd/conf/httpd.conf`)
```
Include conf/extra/fcgi-pica.conf
```

Also you need to have 3 modules enabled:

- `proxy`
- `proxy_fcgi`
- `headers`

Usually you need to uncomment following lines in `/etc/httpd/conf/httpd.conf`
```
LoadModule headers_module modules/mod_headers.so
LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_fcgi_module modules/mod_proxy_fcgi.so
```

In case you use debian-like distro (ubuntu) you should use `a2enmod` command instead:
```
# a2enmod proxy_fcgi
```
This should enable all modules, because module `proxy_fcgi` has module `proxy` as a dependency, and headers are supposed to be enabled.

Start apache

```
$ sudo systemctl start httpd
```

#### Database
You're also goint to need a database server. For now only MySQL/Mariadb is supported. I'm going to use Mariadb as an example.

First - install mariadb (the server!). Set it up, edit config, run whatever it asks you to run on installation. Making configurations, **make sure it creates a unix socket at `/run/mysqld/mysqld.sock` and user running pica has permissions to write to this socket!** By default it does, so, you're probably okay with default configuration.

Next you need to login to mariadb database server, usually it's done like so:
```
$ mariadb -u root -p
```

It will query your password, and then you should see mariadb propt. There you need to execute following commands:
```sql
CREATE DATABASE pica;
CREATE USER 'pica'@'localhost' IDENTIFIED BY 'pica';
GRANT ALL PRIVILEGES ON pica.* TO 'pica'@'localhost';
FLUSH PRIVILEGES;
```

Flushing privileges is not really needed, but it's typicaly written. After that just quit mariadb with `quit;` command.

#### Creating a directory
Next you need to create a directory for pica socket file
```
# mkdir /run/pica
# chown <your user> /run/pica
```

#### Running an app
At this stage we're redy to run an app
```
$ cd build
$ ./pica
```