# MMDB2 File Format Decoder

## Setup

Add the module as a dependency to your `mix.exs` file:

```elixir
defp deps do
  [
    {:mmdb2_decoder, "~> 0.2.0"}
  ]
end
```

Depending on your elixir version you should also update your application list:

```elixir
def application do
  [
    included_applications: [:mmdb2_decoder]
  ]
end
```

## Usage

```elixir
# "regular" flow
database = File.read!("/path/to/database.mmdb")
{meta, tree, data} = MMDB2Decoder.parse_database(database)

{:ok, ip} = :inet.parse_address(String.to_charlist("8.8.8.8"))

MMDB2Decoder.lookup(ip, meta, tree, data)

# "piping" flow
"/path/to/database.mmdb"
|> File.read!()
|> MMDB2Decoder.parse_database()
|> MMDB2Decoder.pipe_lookup({8, 8, 8, 8})
```

### Floating Point Precision

Please be aware that all values of the type `float` are rounded to 4 decimal
digits and `double` values to 8 decimal digits.

This might be changed in the future if there are datasets known to return
values with a higher precision.


## License

[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0)

License information about the supported
[MaxMind GeoIP2 Country](http://www.maxmind.com/en/country),
[MaxMind GeoIP2 City](http://www.maxmind.com/en/city) and
[MaxMind GeoLite2](http://dev.maxmind.com/geoip/geoip2/geolite2/) databases
can be found on their respective sites.