This package allows to extract structured data from bluetooth-based remote scales and provides a management interface to control said devices. Usage is fairly trivial (see examples directory for a simple console logger implementation and a tool for controlling basic functions).
- Control of basic settings (via multiple interfaces)
- Status
- Battery level
- Weight unit
- Measurement precision
- Buzzer
- Extraction of scale data (both channel and handler concept supported)
- Timestamp
- Weight / Unit
- Timer functionality
- REST API wrapper (optional) to support remote interaction with scale functions
go get -u github.com/fako1024/btscaleThe following API interfaces / methods are exposed:
// Basic denotes a basic coffee scale
type Basic interface {
// ConnectionStatus returns the current connection status of the scale device
ConnectionStatus() ConnectionStatus
// BatteryLevel returns the current battery level
BatteryLevel() float64
// BatteryLevelRaw returns the current battery level in its raw form
BatteryLevelRaw() int
// Unit returns the current weight unit
Unit() Unit
// SetUnit sets the weight unit
SetUnit(unit Unit) error
// Tare tares the scale
Tare() error
// TogglePrecision toggles the weight precision between 0.1 and 0.01
TogglePrecision() error
// SetStateChangeHandler defines a handler function that is called upon state change
SetStateChangeHandler(fn func(status ConnectionStatus))
// SetStateChangeChannel defines a handler function that is called upon state change
SetStateChangeChannel(ch chan ConnectionStatus)
// SetDataHandler defines a handler function that is called upon retrieval of data
SetDataHandler(fn func(data DataPoint))
// SetDataChannel defines a handler function that is called upon retrieval of data
SetDataChannel(ch chan DataPoint)
// Close terminates the connection to the device
Close() error
}
// Buzzer denotes audible signaling functionality
type Buzzer interface {
// IsBuzzingOnTouch returs if the buzzer (on user interaction) is on / off
IsBuzzingOnTouch() bool
// ToggleBuzzingOnTouch turns the buzzer (on user interaction) on / off
ToggleBuzzingOnTouch() error
// Buzz requests the scale to beep / buzz n times
Buzz(n int) error
}
// Timer denotes timer / stopwatch functionality
type Timer interface {
// StartTimer starts the timer / stopwatch
StartTimer() error
// StopTimer stops the timer / stopwatch
StopTimer() error
// ResetTimer resets the timer / stopwatch
ResetTimer() error
// ElapsedTime returns the current timer value
ElapsedTime() time.Duration
}
// WithTimer denotes a scale with timer functionality
type WithTimer interface {
Basic
Timer
}
// WithBuzzer denotes a scale with buzzer functionality
type WithBuzzer interface {
Basic
Buzzer
}
// Scale denotes the "default" scale containing all functionality
type Scale interface {
Basic
Buzzer
Timer
}
// Initialize a simple logger for convenience
log := logrus.StandardLogger()
// Initialize a new Felicita bluetooth scale
s, err := felicita.New()
if err != nil {
log.Fatalf("Error opening Felicita scale: %s", err)
}
// Start up the REST API on port 8090 (all interfaces)
api.New(s, ":8090")
// Set a data channel to continuously log incoming data
dataChan := make(chan scale.DataPoint, 256)
s.SetDataChannel(dataChan)
// Setup a state handler to notify upon connection status change
s.SetStateChangeHandler(func(status scale.ConnectionStatus) {
log.Warnf("State change: %v", status)
})
// Setup a signal channel to gracefully disconnect the bluetooth device upon termination
sigChan := make(chan os.Signal)
signal.Notify(sigChan, syscall.SIGTERM)
signal.Notify(sigChan, os.Interrupt)
go func() {
<-sigChan
log.Infof("Got signal, terminating connection to device")
s.Close()
os.Exit(0)
}()
for v := range dataChan {
log.Warnf("Read DATA from Channel: %v, %v, %v, %v, %v", v, s.ConnectionStatus(), s.BatteryLevel(), s.IsBuzzingOnTouch(), s.ElapsedTime())
}For additional examples please refer to the cmd folder.