Strongly SignalK

A strongly typed SignalK library written in TypeScript. Can be used in JavaScript and TypeScript projects.

This library is designed for developers writing interactive marine apps and need to manipulate data in SignalK format.

A strong design decision is that the in-memory representation should be directly compatible with SignalK via JSON.serialize() calls.

Inversely, any valid SignalK file can be parsed and loaded by strongly-signalk.

However, another strong design decision is to not implement all the subtle and less used attributes of the SignalK specification which means that some signalK files that are valid may lose some information when they are parsed into strongly-signalk.

How to use

Load files

SaltedRosetta provides different methods to load files from their filename (on disk, in a node context), from a File object (browser), from a Response object (node and browser) or from a string.

The format of the file will be automatically detected.

import { SaltedRosetta } from strongly-signalk;

let skDeltas = SaltedRosetta.fromFilename('myfile.log')
let myBoatDelta = skDeltas[0]

SaltedRosetta returns a list of SKDelta objects. By convention, the first one is always the "main" delta (the delta of your boat). If the log includes information about other boats, there will be additional SKDelta objects.

Analyze files

import { BetterDataProvider } from strongly-signalk;

const dataProvider = new BetterDataProvider(myBoatDelta)

const availablePaths = dataProvider.getAvailableValues()

// Return an object { [path:string]: SKValueType }
// Values are interpolated to provide a continuous representation over time.
const values = dataProvider.getValuesAtTime(aDateObject)
console.log(`SOG was: ${ values['navigation.speedOverGround'] }`)
console.log(`Position was: ${ values['navigation.position'].asDMSString() }`)

And also:

import { SignalKTripAnalyzer } from strongly-signalk;

// Returns a list of positions - the trace included in the delta
SignalKTripAnalyzer.getPath(myBoatDelta)

// Returns the bounds of the trace
SignalKTripAnalyzer.getBounds(myBoatDelta)

// Returns time bounds of data in a delta object
SignalKTripAnalyzer.getStartTime(myBoatDelta)
SignalKTripAnalyzer.getEndTime(myBoatDelta)

Command Line Interface

Convert a supported file to SignalK data

$ node dist/cli/CLI.js some-supported-file.log
{
  "context": "vessels.self",
  "updates": [
    {
      "timestamp": "2018-07-10T08:00:00.012Z",
      "source": {
        "label": "NMEA2000",
        "pgn": 130306,
        "src": "105",
        "type": "NMEA2000"
...

Show a summary of a file:

• List of included SignalK path/values
• Bounds
• Time bounds
• Simplified path

$  node dist/cli/CLI.js --summary some-supported-file.log
Context: vessels.self - 1846570 updates and 2533140 values
Included SignalK paths: electrical.batteries.dc3.voltage,electrical.batteries.engine.voltage,electrical.batteries.house.voltage,electrical.batteries.kbox-supply.voltage,environment.depth.belowTransducer,environment.inside.engineRoom.temperature,environment.outside.pressure,environment.water.temperature,environment.wind.angleApparent,environment.wind.speedApparent,navigation.attitude,navigation.courseGreatCircle.bearingTrackTrue,navigation.courseGreatCircle.nextPoint.bearingTrue,navigation.courseGreatCircle.nextPoint.distance,navigation.courseGreatCircle.nextPoint.position,navigation.courseGreatCircle.nextPoint.timeToGo,navigation.courseGreatCircle.nextPoint.velocityMadeGood,navigation.courseOverGroundMagnetic,navigation.courseOverGroundTrue,navigation.courseRhumbline.nextPoint.position,navigation.currentRoute.name,navigation.currentRoute.waypoints,navigation.datetime,navigation.gnss.antennaAltitude,navigation.gnss.differentialAge,navigation.gnss.differentialReference,navigation.gnss.geoidalSeparation,navigation.gnss.horizontalDilution,navigation.gnss.integrity,navigation.gnss.methodQuality,navigation.gnss.positionDilution,navigation.gnss.satellites,navigation.gnss.type,navigation.headingMagnetic,navigation.log,navigation.magneticVariation,navigation.magneticVariationAgeOfService,navigation.position,navigation.rateOfTurn,navigation.speedOverGround,navigation.speedThroughWater,navigation.speedThroughWaterReferenceType,navigation.trip.log,notifications.instrument.NoFix,steering.rudderAngle
Bounds: -117.37541216666668,32.83565016666667 -117.20893,32.6481391
Start: 2018-05-11T02:02:42.625Z
End: 2018-05-11T07:10:04.703Z
Path: [[-117.37541216666668,32.83565016666667],[-117.2915456,32.6891026],[-117.2450925,32.6513145],[-117.2258069,32.6529853],[-117.2298686,32.7026236],[-117.2089823,32.7264535]]

License

MIT