MaxMind DB Reader
Description
This is the .NET API for reading MaxMind DB files. MaxMind DB is a binary file format that stores data indexed by IP address subnets (IPv4 or IPv6).
Requirements
This library works with .NET Framework version 4.5 and above.
Installation
NuGet
We recommend installing this library with NuGet. To do this, type the following into the Visual Studio Package Manager Console:
install-package MaxMind.Db
Usage
Note: For accessing MaxMind GeoIP2 databases, we generally recommend using the GeoIP2 .NET API rather than using this package directly.
To use the API, you must first create a Reader
object. The constructor for
the reader object takes a string
with the path to the MaxMind DB file.
Optionally you may pass a second parameter with a FileAccessMode
enum with
the value MemoryMapped
or Memory
. The default mode is MemoryMapped
,
which maps the file to virtual memory. This often provides performance
comparable to loading the file into real memory with the Memory
mode while
using significantly less memory.
To look up an IP address, pass a string
representing the IP address to the
Find<T>
method on Reader
. This method will return the result as type T
.
T
may either be a generic collection or a class using the
[MaxMind.Db.Constructor]
attribute to declare which constructor to use
during deserialization and the [MaxMind.Db.Parameter("name")]
to map the
database key name
to a particular constructor parameter.
We recommend reusing the Reader
object rather than creating a new one for
each lookup. The creation of this object is relatively expensive as it must
read in metadata for the file.
Example
using (var reader = new Reader("GeoIP2-City.mmdb"))
{
var data = reader.Find<Dictionary<string, object>>("24.24.24.24");
...
}
Multi-Threaded Use
This API fully supports use in multi-threaded applications. In such
applications, we suggest creating one Reader
object and sharing that among
threads.
Format
The MaxMind DB format is an open format for quickly mapping IP addresses to records. See [the specification] (https://github.com/maxmind/MaxMind-DB/blob/master/MaxMind-DB-spec.md) for more information on the format.
Bug Tracker
Please report all issues with this code using the [GitHub issue tracker] (https://github.com/maxmind/MaxMind-DB-Reader-dotnet/issues).
If you are having an issue with a MaxMind database or service that is not specific to this reader, please [contact MaxMind support] (http://www.maxmind.com/en/support).
Contributing
Patches and pull requests are encouraged. Please include unit tests whenever possible.
Versioning
The MaxMind DB Reader API uses Semantic Versioning.
Copyright and License
This software is Copyright (c) 2016 by MaxMind, Inc.
This is free software, licensed under the Apache License, Version 2.0.