@Yermo/nativescript-background-geolocation-fbs

This is a port of https://github.com/mauron85/cordova-plugin-background-geolocation to NativeScript.

This version of the API relies heavily on promises instead of the callback structure used by the cordova plugin. See API below.

The majority of this documentation comes from the cordova plugin repository managed by @mauron85.

Demo

There is well commented NativeScript + Angular sample app in ./demo-angular which demonstrates the basics of using the plugin.

Running the demo on Android

You must have NativeScript installed and the 'tns' command must be in your path.

To run it on Android in an emulator:

cd src
npm install
npm run demo-angular.android

The emulator supports simulating GPS locations. Open up the Extended Controls screen and check out the Location page.

Running the demo on a live device with simulated location data

Simulating GPS locations in the Android emulator, at least in my experience under Ubuntu, is ridiculously slow so I use a real device for testing.

To simulate GPS locations on a live device I have been using the "Lockito" app which seems to work.

https://play.google.com/store/apps/details?id=fr.dvilleneuve.lockito&hl=en_US

After installing the app, you must enable it in developer options. The setting under Developers Options is *** Select mock locations app ***.

If you are under Linux or MacOSX, there is a script in ./etc/fake_gps.sh that will feed locations to the lockito app for testing.

You must have the Android SDK installed and the 'adb' command must be in your path.

• connect your device via USB
• open the lockito app
• press start in the lockito app
• cd src; npm run build
• cd ../demo-angular
• tns run android
• press the 'START' button in the ngdemo app
• in another terminal window run ./etc/fake_gps.sh

You should see the location data update.

*** If you do not see location updates check the Settings Page. Under Android the default intervals are too long so you can reduce them. You can also try the RAW LOCATION PROVIDER ***

Running the demo on iOS

Make sure to have Nativescript installed.

cd src
npm run plugin.prepare
npm run demo-angular.ios

The iOS simulator supports simulating location data. Go to Debug->Location->Freeway Drive for example.

Heap Errors

If you get javascript out of heap errors do when trying to build this use:

export NODE_OPTIONS=--max-old-space-size=4096

Submitting issues

All new issues should follow instructions in ISSUE_TEMPLATE.md. A properly filled issue report will significantly reduce number of follow up questions and decrease issue resolving time. Most issues cannot be resolved without debug logs. Please try to isolate debug lines related to your issue. Instructions for how to prepare debug logs can be found in section Debugging. If you're reporting an app crash, debug logs might not contain all the necessary information about the cause of the crash. In that case, also provide relevant parts of output of adb logcat command.

Android background service issues

There are repeatedly reported issues with some android devices not working in the background. Check if your device model is on dontkillmyapp list before you report new issue. For more information check out dontkillmyapp.com.

Description

Cross-platform geolocation for NativeScript on iOS and Android with battery-saving "circular region monitoring" and "stop detection".

This plugin can be used for geolocation when the app is running in the foreground or background. It provides features that focus on limiting battery drain.

You can choose from three location location providers:

• DISTANCE_FILTER_PROVIDER
• ACTIVITY_PROVIDER
• RAW_PROVIDER

See Which provider should I use? for more information about providers.

Status

As of this writing, posting locations to a server is not implemented. If it's a feature you need, please let me know.

Installing the plugin

tns plugin add @Yermo/nativescript-background-geolocation-fbs

You may also want to change default iOS permission prompts and set specific google play version and android support library version for compatibility with other plugins.

FIXME: Add instructions for AndroidManifest.xml and app.gradle

Android

You will need to ensure that you have the following items installed through the Android SDK Manager:

Name	Version
Android SDK Tools	26.0.2
Android SDK Platform-tools	26.0.2
Android SDK Build-tools	26.0.2
Android Support Repository	47
Android Support Library	26.1.0
Google Play Services	11.8.0
Google Repository	58

Android is no longer supporting downloading support libraries through the SDK Manager. The support libraries are now available through Google's Maven repository.

Example

  BackgroundGeolocationFbs.configure({
    locationProvider: BackgroundGeolocation.ACTIVITY_PROVIDER,
    desiredAccuracy: BackgroundGeolocation.HIGH_ACCURACY,
    stationaryRadius: 50,
    distanceFilter: 50,
    notificationTitle: 'Background tracking',
    notificationText: 'enabled',
    debug: true,
    interval: 10000,
    fastestInterval: 5000,
    activitiesInterval: 10000,
    url: 'http://192.168.81.15:3000/location',
    httpHeaders: {
      'X-FOO': 'bar'
    },
    // customize post properties
    postTemplate: {
      lat: '@latitude',
      lon: '@longitude',
      foo: 'bar' // you can also add your own properties
    }
  }).then( () => {

    BackgroundGeolocation.on('location', ( location ) => {
      // handle your locations here
      // to perform long running operation on iOS
      // you need to create background task

      BackgroundGeolocation.startTask().then( (taskKey) => {
        // execute long running task
        // eg. ajax post location
        // IMPORTANT: task has to be ended by endTask
        BackgroundGeolocation.endTask(taskKey);
      });
    });

    BackgroundGeolocation.on('stationary', (stationaryLocation) => {
      // handle stationary locations here
    });

    BackgroundGeolocation.on('error', (error) => {
      console.log('[ERROR] BackgroundGeolocation error:', error.code, error.message);
    });

    BackgroundGeolocation.on('start', () => {
      console.log('[INFO] BackgroundGeolocation service has been started');
    });

    BackgroundGeolocation.on('stop', () => {
      console.log('[INFO] BackgroundGeolocation service has been stopped');
    });

    BackgroundGeolocation.on('authorization', (status) => {
      console.log('[INFO] BackgroundGeolocation authorization status: ' + status);
      if (status !== BackgroundGeolocation.AUTHORIZED) {
        // we need to set delay or otherwise alert may not be shown
        setTimeout(function() {
          var showSettings = confirm('App requires location tracking permission. Would you like to open app settings?');
          if (showSetting) {
            return BackgroundGeolocation.showAppSettings();
          }
        }, 1000);
      }
    });

    BackgroundGeolocation.on('background', () => {
      console.log('[INFO] App is in background');
      // you can also reconfigure service (changes will be applied immediately)
      BackgroundGeolocation.configure({ debug: true });
    });

    BackgroundGeolocation.on('foreground', () => {
      console.log('[INFO] App is in foreground');
      BackgroundGeolocation.configure({ debug: false });
    });

    BackgroundGeolocation.on('abort_requested', () => {
      console.log('[INFO] Server responded with 285 Updates Not Required');

      // Here we can decide whether we want stop the updates or not.
      // If you've configured the server to return 285, then it means the server does not require further update.
      // So the normal thing to do here would be to `BackgroundGeolocation.stop()`.
      // But you might be counting on it to receive location updates in the UI, so you could just reconfigure and set `url` to null.
    });

    BackgroundGeolocation.on('http_authorization', () => {
      console.log('[INFO] App needs to authorize the http requests');
    });

    BackgroundGeolocation.checkStatus().then( (status) => {
      console.log('[INFO] BackgroundGeolocation service is running', status.isRunning);
      console.log('[INFO] BackgroundGeolocation services enabled', status.locationServicesEnabled);
      console.log('[INFO] BackgroundGeolocation auth status: ' + status.authorization);

      // you don't need to check status before start (this is just the example)

      if (!status.isRunning) {
        BackgroundGeolocation.start(); //triggers start on start event
      }
    }).catch( (error ) => {
      console.log( "checkStatus returned an error:", error );
    });

    // you can also just start without checking for status
    // BackgroundGeolocation.start();

    // Don't forget to remove listeners at some point!
    // BackgroundGeolocation.removeAllListeners();
  }

API

configure(options).then( success ).catch( fail )

Configure options:

Parameter	Type	Platform	Description	Provider*	Default
locationProvider	Number	all	Set location provider @see PROVIDERS	N/A	DISTANCE_FILTER_PROVIDER
desiredAccuracy	Number	all	Desired accuracy in meters. Possible values [HIGH_ACCURACY, MEDIUM_ACCURACY, LOW_ACCURACY, PASSIVE_ACCURACY]. Accuracy has direct effect on power drain. Lower accuracy = lower power drain.	all	MEDIUM_ACCURACY
stationaryRadius	Number	all	Stationary radius in meters. When stopped, the minimum distance the device must move beyond the stationary location for aggressive background-tracking to engage.	DIS	50
debug	Boolean	all	When enabled, the plugin will emit sounds for life-cycle events of background-geolocation! See debugging sounds table.	all	false
distanceFilter	Number	all	The minimum distance (measured in meters) a device must move horizontally before an update event is generated. @see Apple docs.	DIS,RAW	500
stopOnTerminate	Boolean	all	Enable this in order to force a stop() when the application terminated (e.g. on iOS, double-tap home button, swipe away the app).	all	true
startOnBoot	Boolean	Android	Start background service on device boot.	all	false
interval	Number	Android	The minimum time interval between location updates in milliseconds. @see Android docs for more information.	all	60000
fastestInterval	Number	Android	Fastest rate in milliseconds at which your app can handle location updates. @see Android docs.	ACT	120000
activitiesInterval	Number	Android	Rate in milliseconds at which activity recognition occurs. Larger values will result in fewer activity detections while improving battery life.	ACT	10000
stopOnStillActivity	Boolean	Android	@deprecated stop location updates, when the STILL activity is detected	ACT	true
notificationsEnabled	Boolean	Android	Enable/disable local notifications when tracking and syncing locations	all	true
startForeground	Boolean	Android	Allow location sync service to run in foreground state. Foreground state also requires a notification to be presented to the user.	all	false
notificationTitle	String optional	Android	Custom notification title in the drawer. (goes with startForeground)	all	"Background tracking"
notificationText	String optional	Android	Custom notification text in the drawer. (goes with startForeground)	all	"ENABLED"
notificationIconColor	String optional	Android	The accent color to use for notification. Eg. #4CAF50. (goes with startForeground)	all
notificationIconLarge	String optional	Android	The filename of a custom notification icon. @see Android quirks. (goes with startForeground)	all
notificationIconSmall	String optional	Android	The filename of a custom notification icon. @see Android quirks. (goes with startForeground)	all
activityType	String	iOS	[AutomotiveNavigation, OtherNavigation, Fitness, Other] Presumably, this affects iOS GPS algorithm. @see Apple docs for more information	all	"OtherNavigation"
pauseLocationUpdates	Boolean	iOS	Pauses location updates when app is paused. *@see Apple docs	all	false
saveBatteryOnBackground	Boolean	iOS	Switch to less accurate significant changes and region monitory when in background	all	false
url	String	all	Server url where to send HTTP POST with recorded locations @see HTTP locations posting	all
syncUrl	String	all	Server url where to send fail to post locations @see HTTP locations posting	all
syncThreshold	Number	all	Specifies how many previously failed locations will be sent to server at once	all	100
httpHeaders	Object	all	Optional HTTP headers sent along in HTTP request	all
maxLocations	Number	all	Limit maximum number of locations stored into db	all	10000
postTemplate	Object|Array	all	Customization post template @see Custom post template	all

* DIS = DISTANCE_FILTER_PROVIDER ACT = ACTIVITY_PROVIDER RAW = RAW_PROVIDER

Partial reconfiguration is possible by later providing a subset of the configuration options:

BackgroundGeolocation.configure({
  debug: true
});

In this case new configuration options will be merged with stored configuration options and changes will be applied immediately.

Important: Because configuration options are applied partially, it's not possible to reset an option to its default value just by emitting it's key name and calling configure method. To reset a configuration option to the default value, it's key must be set to null!

// Example: reset postTemplate to default
BackgroundGeolocation.configure({
  postTemplate: null
});

getConfig().then( (config) => { successFn } ).catch( ( error ) => {failFn} );

Platform: iOS, Android

Get current configuration. Method will return a promise that resolves with all configuration options and their values. Because configure method can be called with subset of the configuration options only, getConfig method can be used to check the actual applied configuration.

BackgroundGeolocation.getConfig().then( (config) => {
  console.log(config);
});

start().then( () => { successFn } ).catch( ( error ) => { errorFn } );

Platform: iOS, Android

Start background geolocation.

stop().then( () => { successFn } ).catch( ( error ) => { errorFn } );

Platform: iOS, Android

Stop background geolocation.

getCurrentLocation( timeout : number, maxAge : number, enableHighAccuracy : boolean ).then( ( location ) => { successFn } ).catch( (error) => {errorFn} );

Platform: iOS, Android

One time location check to get current location of the device.

Option parameter	Type	Description
timeout	Number	Maximum time in milliseconds device will wait for location
maximumAge	Number	Maximum age in milliseconds of a possible cached location that is acceptable to return
enableHighAccuracy	Boolean	if true and if the device is able to provide a more accurate position, it will do so

Promise resolves	Type	Description
location	Object	location object (@see Location event)

Promise rejection	Type	Description
code	Number	Reason of an error occurring when using the geolocating device
message	String	Message describing the details of the error

Error codes:

Value	Associated constant	Description
1	PERMISSION_DENIED	Request failed due missing permissions
2	LOCATION_UNAVAILABLE	Internal source of location returned an internal error
3	TIMEOUT	Timeout defined by `option.timeout was exceeded

checkStatus().then( (status) => { successFn} ).catch( ( error ) => { errorFn } );

Check status of the service

Success callback parameter	Type	Description
isRunning	Boolean	true/false (true if service is running)
locationServicesEnabled	Boolean	true/false (true if location services are enabled)
authorization	Number	authorization status

Authorization statuses:

• NOT_AUTHORIZED
• AUTHORIZED - authorization to run in background and foreground
• AUTHORIZED_FOREGROUND iOS only authorization to run in foreground only

Note: In the Android concept of authorization, these represent application permissions.

showAppSettings()

Platform: Android >= 6, iOS >= 8.0

Show app settings to allow change of app location permissions.

showLocationSettings()

Platform: Android

Show system settings to allow configuration of current location sources.

getLocations().then( ( locations ) => { successFn }).catch( (error) => { errorFn } );

Platform: iOS, Android

Method will return all stored locations. This method is useful for initial rendering of user location on a map just after application launch.

resolve	Type	Description
locations	Array	collection of stored locations

BackgroundGeolocation.getLocations()
.then( (locations) => {
  console.log(locations);
});

getValidLocations().then( (locations) => { successFn }).catch( (error) => { errorFn } );

Platform: iOS, Android

Method will return locations which have not yet been posted to server.

resolve	Type	Description
locations	Array	collection of stored locations

getNumLocations().then( ( numLocations )=> {successFn} ).catch( (error) => {errorFn} );

Platform: iOS, Android

Returns the number of locations stored in the cache.

deleteLocation( locationId : number ).then( ()=> {successFn} ).catch( (error) => {errorFn} );

Platform: iOS, Android

Delete location with locationId.

deleteAllLocations().then( () => { successFn } ).catch( (error) => { errorFn });

Platform: iOS, Android

Delete all stored locations.

switchMode(modeId).then( () => { successFn } ).catch( (error) => { errorFn } );

Platform: iOS

Normally the plugin will handle switching between BACKGROUND and FOREGROUND mode itself. Calling switchMode you can override plugin behavior and force it to switch into other mode.

In FOREGROUND mode the plugin uses iOS local manager to receive locations and behavior is affected by option.desiredAccuracy and option.distanceFilter.

In BACKGROUND mode plugin uses significant changes and region monitoring to receive locations and uses option.stationaryRadius only.

// switch to FOREGROUND mode
BackgroundGeolocation.switchMode(BackgroundGeolocation.FOREGROUND_MODE);

// switch to BACKGROUND mode
BackgroundGeolocation.switchMode(BackgroundGeolocation.BACKGROUND_MODE);

forceSync()

Platform: Android, iOS

Force sync of pending locations. Option syncThreshold will be ignored and all pending locations will be immediately posted to syncUrl in single batch.

getLogEntries(limit, fromId, minLevel).then( ( entries ) => { successFn } ).catch( (error) => { errorFn });

Platform: Android, iOS

Return all logged events. Useful for plugin debugging.

Parameter	Type	Description
limit	Number	limits number of returned entries
fromId	Number	return entries after fromId. Useful if you plan to implement infinite log scrolling*
minLevel	String	return log entries above level. Available levels: ["TRACE", "DEBUG", "INFO", "WARN", "ERROR]

Format of log entry:

Parameter	Type	Description
id	Number	id of log entry as stored in db
timestamp	Number	timestamp in milliseconds since beginning of UNIX epoch
level	String	log level
message	String	log message
stackTrace	String	recorded stacktrace (Android only, on iOS part of message)

removeAllListeners()

Unregister all event listeners for given event. If parameter event is not provided then all event listeners will be removed.

Events

Name	Callback param	Platform	Provider*	Description
location	Location	all	all	on location update
stationary	Location	all	DIS,ACT	on device entered stationary mode
activity	Activity	Android	ACT	on activity detection
error	{ code, message }	all	all	on plugin error
authorization	status	all	all	on user toggle location service
start		all	all	geolocation has been started
stop		all	all	geolocation has been stopped
foreground		Android	all	app entered foreground state (visible)
background		Android	all	app entered background state
abort_requested		all	all	server responded with "285 Updates Not Required"
http_authorization		all	all	server responded with "401 Unauthorized"

Location event

Location parameter	Type	Description
id	Number	ID of location as stored in DB (or null)
provider	String	gps, network, passive or fused
locationProvider	Number	location provider
time	Number	UTC time of this fix, in milliseconds since January 1, 1970.
latitude	Number	Latitude, in degrees.
longitude	Number	Longitude, in degrees.
accuracy	Number	Estimated accuracy of this location, in meters.
speed	Number	Speed if it is available, in meters/second over ground.
altitude	Number	Altitude if available, in meters above the WGS 84 reference ellipsoid.
bearing	Number	Bearing, in degrees.
isFromMockProvider	Boolean	(android only) True if location was recorded by mock provider
mockLocationsEnabled	Boolean	(android only) True if device has mock locations enabled

Locations parameters isFromMockProvider and mockLocationsEnabled are not posted to url or syncUrl by default. Both can be requested via option postTemplate.

Note: Do not use location id as unique key in your database as ids will be reused when option.maxLocations is reached.

Activity event

Activity parameter	Type	Description
confidence	Number	Percentage indicating the likelihood user is performing this activity.
type	String	"IN_VEHICLE", "ON_BICYCLE", "ON_FOOT", "RUNNING", "STILL",
		"TILTING", "UNKNOWN", "WALKING"

Event listeners can registered with:

const eventSubscription = BackgroundGeolocation.on('event', callbackFn);

And unregistered:

eventSubscription.remove();

Note: Components should unregister all event listeners in componentWillUnmount method, individually, or with removeAllListeners

HTTP locations posting

All locations updates are recorded in the local db at all times. When the App is in foreground or background, in addition to storing location in local db, the location callback function is triggered. The number of locations stored in db is limited by option.maxLocations and never exceeds this number. Instead, old locations are replaced by new ones.

When option.url is defined, each location is also immediately posted to url defined by option.url. If the post is successful, the location is marked as deleted in local db.

When option.syncUrl is defined, all locations that fail to post locations will be coalesced and sent in some time later in a one single batch. Batch sync takes place only when the number of failed-to-post locations reaches option.syncTreshold. Locations are sent only in single batch, when the number of locations reaches option.syncTreshold. (No individual locations will be sent)

The request body of posted locations is always an array, even when only one location is sent.

Warning: option.maxLocations has to be larger than option.syncThreshold. It's recommended to be 2x larger. In any other case the location syncing might not work properly.

Custom post template

With option.postTemplate it is possible to specify which location properties should be posted to option.url or option.syncUrl. This can be useful to reduce the number of bytes sent "over the wire".

All wanted location properties have to be prefixed with @. For all available properties check Location event.

Two forms are supported:

jsonObject

BackgroundGeolocation.configure({
  postTemplate: {
    lat: '@latitude',
    lon: '@longitude',
    foo: 'bar' // you can also add your own properties
  }
});

jsonArray

BackgroundGeolocation.configure({
  postTemplate: ['@latitude', '@longitude', 'foo', 'bar']
});

Note: Keep in mind that all locations (even a single one) will be sent as an array of object(s), when postTemplate is jsonObject and array of array(s) for jsonArray!

Android Headless Task (Experimental)

A special task that gets executed when the app is terminated, but the plugin was configured to continue running in the background (option stopOnTerminate: false). In this scenario the Activity was killed by the system and all registered event listeners will not be triggered until the app is relaunched.

Note: Prefer configuration options url and syncUrl over headless task. Use it sparingly!

Task event

Parameter	Type	Description
event.name	String	Name of the event [ "location", "stationary", "activity" ]
event.params	Object	Event parameters. @see Events

Keep in mind that the callback function lives in an isolated scope. Variables from a higher scope cannot be referenced!

Following example requires CORS enabled backend server.

BackgroundGeolocation.headlessTask(function(event) {
    if (event.name === 'location' ||
      event.name === 'stationary') {
        var xhr = new XMLHttpRequest();
        xhr.open('POST', 'http://192.168.81.14:3000/headless');
        xhr.setRequestHeader('Content-Type', 'application/json');
        xhr.send(JSON.stringify(event.params));
    }

    return 'Processing event: ' + event.name; // will be logged
});

Example of backend server

Background-geolocation-server is a backend server written in nodejs with CORS - Cross-Origin Resource Sharing support. There are instructions how to run it and simulate locations on Android, iOS Simulator and Genymotion.

Quirks

iOS

On iOS the plugin will execute your registered .on('location', callbackFn) callback function. You may manually POST the received Geolocation to your server using standard XHR. However for long running tasks, you need to wrap your code in startTask - endTask block.

stationaryRadius (apply only for DISTANCE_FILTER_PROVIDER)

The plugin uses iOS Significant Changes API, and starts triggering callbackFn only when a cell-tower switch is detected (i.e. the device exits stationary radius). The function switchMode is provided to force the plugin to enter "BACKGROUND" stationary or "FOREGROUND" mode.

Plugin cannot detect the exact moment the device moves out of the stationary-radius. In normal conditions, it can take as much as 3 city-blocks to 1/2 km before stationary-region exit is detected.

Android

On Android devices it is recommended to have a notification in the drawer (option startForeground:true). This gives plugin location service higher priority, decreasing probability of OS killing it. Check wiki for explanation.

Custom ROMs

Plugin should work with custom ROMS at least DISTANCE_FILTER_PROVIDER. But ACTIVITY_PROVIDER provider depends on Google Play Services. Usually ROMs don't include Google Play Services libraries. Strange bugs may occur, like no GPS locations (only from network and passive) and other. When posting issue report, please mention that you're using custom ROM.

Android Permissions

Android 6.0 "Marshmallow" introduced a new permissions model where the user can turn on and off permissions as necessary. When user disallow location access permissions, error configure callback will be called with error code: 2.

Notification icons

Note: Only available for API Level >=21.

To use custom notification icons, you need to put icons into res/drawable directory of your app. You can automate the process as part of after_platform_add hook configured via config.xml. Check config.xml and scripts/res_android.js of example app for reference.

If you only want a single large icon, set notificationIconLarge to null and include your icon's filename in the notificationIconSmall parameter.

With Adobe® PhoneGap™ Build icons must be placed into locales/android/drawable dir at the root of your project. For more information go to how-to-add-native-image-with-phonegap-build.

Intel XDK

Plugin will not work in XDK emulator ('Unimplemented API Emulation: BackgroundGeolocation.start' in emulator). But will work on real device.

Debugging

See DEBUGGING.md

Changelog

See CHANGES.md

Licence

This plugin is based on work by @mauron85 and carries the same license.

Copyright (c) 2019 Yermo Lamers, Flying Brick Software, LLC

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.