VpnHood.Assets.Ip2LocationLite 7.0.748

VpnHood.Assets.IpLocations

The IP2Location LITE country database as an inert asset package: data plus MSBuild targets, and no compiled code. Nothing in your codebase can take a reference on it — it is a store of bytes, not a library.

<PackageReference Include="VpnHood.Assets.Ip2LocationLite" />

That is the whole integration. The package's targets place IpLocations.zip where your app's platform keeps files, and you read it from the asset path iplocations/IpLocations.zip. That path is the entire contract between this package and your code.

Why it is data and not an embedded resource

.NET for Android keeps assemblies once per CPU architecture. A 14.6 MB database compiled into a DLL is therefore carried once per ABI — three or four times over in a multi-ABI package. Placed as data it is carried once, in the part of the package Android does not split by architecture.

Reading it as a stream rather than a byte[] also keeps those 14.6 MB out of the managed heap: the zip's entries are stored, not deflated, so a reader seeks straight to the country it wants.

Where the file lands

The targets live in buildTransitive/, so an app that reaches this package through another package or project gets the file placed just the same, at any depth. Only an app's build places it; a library that merely passes the reference along gets no 14.6 MB copy in its bin.

Reading it

Windows, Linux, iOS, tvOS, Mac Catalyst

An ordinary file, under AppContext.BaseDirectory:

var path = Path.Combine(AppContext.BaseDirectory, "iplocations", "IpLocations.zip");
using var zip = new ZipArchive(File.OpenRead(path), ZipArchiveMode.Read);

Android — read it in place, do not copy it

On Android the asset is not a file. It is an entry of the .apk, and AssetManager.Open returns a forward-only stream, which ZipArchive cannot use because it seeks.

Do not solve that by copying the asset to the cache folder: that spends another 14.6 MB of the user's storage on bytes the app already carries. Read it where it lies instead. OpenFd gives the entry's offset and length inside the .apk, and the .apk is an ordinary file, so a window onto that byte range is an ordinary seekable stream:

// 1. where the entry lies inside the package
using var descriptor = context.Assets.OpenFd("iplocations/IpLocations.zip");
var packagePath = context.ApplicationInfo.SourceDir;

// 2. a seekable window onto that range - nothing is copied
var stream = new SubStream(File.OpenRead(packagePath), descriptor.StartOffset, descriptor.Length);
using var zip = new ZipArchive(stream, ZipArchiveMode.Read);

SubStream here is any read-only, seekable window over another stream: position 0 is the window's start, its length is the window's length, and each read is served from offset + position of the source. It is about sixty lines, and it is the only code this package's Android support needs.

The entry must be stored, not deflated, or OpenFd has no file descriptor to hand out and throws. This package's targets already arrange that by adding .zip to AndroidStoreUncompressedFileExtensions for the consuming app, so it works out of the box; if you place the file yourself, you have to do the same.

What is in the zip

One entry per country, named by its lower-case ISO code (tr.ips), holding that country's IP ranges already sorted and unified, plus _checksum.txt naming the build of the data. Every entry is stored uncompressed.

Data source

This package includes IP geolocation data from IP2Location LITE. IP2Location LITE is Copyright (c) Hexasoft Development Sdn. Bhd. All Rights Reserved.

License & attribution

This package requires attribution under IP2Location LITE's license. If you use it, you must acknowledge IP2Location LITE as follows:

This nuget uses the IP2Location LITE database for IP geolocation.

For more details, visit the IP2Location LITE license.