README.md

TAKPacket-SDK — C# / .NET

The .NET binding of TAKPacket-SDK: convert ATAK Cursor-on-Target (CoT) XML to Meshtastic's TAKPacketV2 protobuf and compress it with zstd dictionary compression for LoRa mesh transport (237-byte MTU, port 78). Wire payloads are byte-interoperable with the Kotlin, Swift, Python, and TypeScript bindings.

Targets .NET 9. Depends on Google.Protobuf and ZstdSharp.Port.

📚 API reference (DocFX)

Install

dotnet add package Meshtastic.TAK

Quick start

using Meshtastic.TAK;

var parser = new CotXmlParser();
var compressor = new TakCompressor();
var builder = new CotXmlBuilder();

// Sanitize raw ATAK CoT XML before parsing.
var clean = CotMeshSanitizer.NormalizeCotXml(cotXmlString);
clean = CotMeshSanitizer.StripNonEssentialForMesh(clean);

var packet = parser.Parse(clean);
byte[] wirePayload = compressor.Compress(packet);   // [flags][zstd body], ≤ 237 B

// Receive side
var received = compressor.Decompress(wirePayload);
string cotXml = builder.Build(received);

Core classes

Class	Responsibility
CotMeshSanitizer	Mesh hygiene on raw CoT XML before parsing
CotXmlParser	CoT XML → TakPacketV2Data
CotXmlBuilder	TakPacketV2Data → CoT XML
TakCompressor	TakPacketV2Data ↔ compressed wire payload
CotTypeMapper	CoT type string ↔ enum, aircraft classification
AtakPalette	ATAK 14-color palette ↔ Team enum
DictionaryProvider	Selects and loads the embedded zstd dictionaries

Errors

TakCompressor.Decompress throws on a malformed frame or one that would expand past 4096 bytes (decompression-bomb guard). The parser rejects DTD/entity declarations (XXE hardening).

Build & test (contributors)

cd csharp
dotnet build
dotnet test
dotnet tool install -g docfx && docfx docfx.json   # API docs → _site/

See the repository CONTRIBUTING guide and WIRE_FORMAT.md.