Merge pull request hybridgroup#155 from hybridgroup/errors

Add error handling

Makefile

@@ -3,13 +3,13 @@ PACKAGES := gobot gobot/api gobot/platforms/intel-iot/edison gobot/sysfs $(shell
 
 test:
 	for package in $(PACKAGES) ; do \
-		go test github.com/hybridgroup/$$package ; \
+		go test -a github.com/hybridgroup/$$package ; \
 	done ; \
 
 cover:
 	echo "mode: count" > profile.cov ; \
 	for package in $(PACKAGES) ; do \
-		go test -covermode=count -coverprofile=tmp.cov github.com/hybridgroup/$$package ; \
+		go test -a -covermode=count -coverprofile=tmp.cov github.com/hybridgroup/$$package ; \
 		cat tmp.cov | grep -v "mode: count" >> profile.cov ; \
 	done ; \
 	rm tmp.cov ; \

adaptor.go

@@ -11,8 +11,8 @@ type Adaptor struct {
 
 // AdaptorInterface defines behaviour expected for a Gobot Adaptor
 type AdaptorInterface interface {
-	Finalize() bool
-	Connect() bool
+	Finalize() []error
+	Connect() []error
 	Port() string
 	Name() string
 	Type() string

connection.go

@@ -2,6 +2,7 @@ package gobot
 
 import (
 	"errors"
+	"fmt"
 	"log"
 )
 
@@ -28,26 +29,33 @@ func (c *connections) Each(f func(Connection)) {
 }
 
 // Start initializes all the connections.
-func (c *connections) Start() error {
-	var err error
+func (c *connections) Start() (errs []error) {
 	log.Println("Starting connections...")
 	for _, connection := range *c {
 		info := "Starting connection " + connection.Name()
 		if connection.Port() != "" {
 			info = info + " on port " + connection.Port()
 		}
 		log.Println(info + "...")
-		if connection.Connect() == false {
-			err = errors.New("Could not start connection")
-			break
+		if errs = connection.Connect(); len(errs) > 0 {
+			for i, err := range errs {
+				errs[i] = errors.New(fmt.Sprintf("Connection %q: %v", connection.Name(), err))
+			}
+			return
 		}
 	}
-	return err
+	return
 }
 
 // Finalize finishes all the connections.
-func (c *connections) Finalize() {
+func (c *connections) Finalize() (errs []error) {
 	for _, connection := range *c {
-		connection.Finalize()
+		if cerrs := connection.Finalize(); cerrs != nil {
+			for i, err := range cerrs {
+				cerrs[i] = errors.New(fmt.Sprintf("Connection %q: %v", connection.Name(), err))
+			}
+			errs = append(errs, cerrs...)
+		}
 	}
+	return errs
 }

device.go

@@ -2,6 +2,7 @@ package gobot
 
 import (
 	"errors"
+	"fmt"
 	"log"
 )
 
@@ -30,26 +31,33 @@ func (d *devices) Each(f func(Device)) {
 }
 
 // Start starts all the devices.
-func (d *devices) Start() error {
-	var err error
+func (d *devices) Start() (errs []error) {
 	log.Println("Starting devices...")
 	for _, device := range *d {
 		info := "Starting device " + device.Name()
 		if device.Pin() != "" {
 			info = info + " on pin " + device.Pin()
 		}
 		log.Println(info + "...")
-		if device.Start() == false {
-			err = errors.New("Could not start device")
-			break
+		if errs = device.Start(); len(errs) > 0 {
+			for i, err := range errs {
+				errs[i] = errors.New(fmt.Sprintf("Device %q: %v", device.Name(), err))
+			}
+			return
 		}
 	}
-	return err
+	return
 }
 
 // Halt stop all the devices.
-func (d *devices) Halt() {
+func (d *devices) Halt() (errs []error) {
 	for _, device := range *d {
-		device.Halt()
+		if derrs := device.Halt(); len(derrs) > 0 {
+			for i, err := range derrs {
+				derrs[i] = errors.New(fmt.Sprintf("Device %q: %v", device.Name(), err))
+			}
+			errs = append(errs, derrs...)
+		}
 	}
+	return
 }

driver.go

@@ -7,8 +7,8 @@ import (
 
 // DriverInterface defines Driver expected behaviour
 type DriverInterface interface {
-	Start() bool
-	Halt() bool
+	Start() []error
+	Halt() []error
 	Adaptor() AdaptorInterface
 	SetInterval(time.Duration)
 	Interval() time.Duration

examples/beaglebone_blinkm.go

@@ -20,7 +20,8 @@ func main() {
 			g := byte(gobot.Rand(255))
 			b := byte(gobot.Rand(255))
 			blinkm.Rgb(r, g, b)
-			fmt.Println("color", blinkm.Color())
+			color, _ := blinkm.Color()
+			fmt.Println("color", color)
 		})
 	}
 

examples/beaglebone_direct_pin.go

@@ -17,7 +17,8 @@ func main() {
 
 	work := func() {
 		gobot.Every(500*time.Millisecond, func() {
-			if button.DigitalRead() == 1 {
+			val, _ := button.DigitalRead()
+			if val == 1 {
 				led.DigitalWrite(1)
 			} else {
 				led.DigitalWrite(0)

examples/edison_blinkm.go

@@ -21,7 +21,8 @@ func main() {
 			g := byte(gobot.Rand(255))
 			b := byte(gobot.Rand(255))
 			blinkm.Rgb(r, g, b)
-			fmt.Println("color", blinkm.Color())
+			color, _ := blinkm.Color()
+			fmt.Println("color", color)
 		})
 	}
 

examples/firmata_blinkm.go

@@ -21,7 +21,8 @@ func main() {
 			g := byte(gobot.Rand(255))
 			b := byte(gobot.Rand(255))
 			blinkm.Rgb(r, g, b)
-			fmt.Println("color", blinkm.Color())
+			color, _ := blinkm.Color()
+			fmt.Println("color", color)
 		})
 	}
 

examples/firmata_hmc6352.go

@@ -17,7 +17,8 @@ func main() {
 
 	work := func() {
 		gobot.Every(100*time.Millisecond, func() {
-			fmt.Println("Heading", hmc6352.Heading)
+			heading, _ := hmc6352.Heading()
+			fmt.Println("Heading", heading)
 		})
 	}
 

examples/raspi_blinkm.go

@@ -20,7 +20,8 @@ func main() {
 			g := byte(gobot.Rand(255))
 			b := byte(gobot.Rand(255))
 			blinkm.Rgb(r, g, b)
-			fmt.Println("color", blinkm.Color())
+			color, _ := blinkm.Color()
+			fmt.Println("color", color)
 		})
 	}
 

gobot.go

@@ -56,19 +56,40 @@ func (g *Gobot) Command(name string) func(map[string]interface{}) interface{} {
 }
 
 // Start runs the main Gobot event loop
-func (g *Gobot) Start() {
-	g.robots.Start()
+func (g *Gobot) Start() (errs []error) {
+	if rerrs := g.robots.Start(); len(rerrs) > 0 {
+		for _, err := range rerrs {
+			log.Println("Error:", err)
+			errs = append(errs, err)
+		}
+	}
 
 	c := make(chan os.Signal, 1)
 	g.trap(c)
+	if len(errs) > 0 {
+		// there was an error during start, so we immediatly pass the interrupt
+		// in order to disconnect the initialized robots, connections and devices
+		c <- os.Interrupt
+	}
 
 	// waiting for interrupt coming on the channel
 	_ = <-c
 	g.robots.Each(func(r *Robot) {
 		log.Println("Stopping Robot", r.Name, "...")
-		r.Devices().Halt()
-		r.Connections().Finalize()
+		if herrs := r.Devices().Halt(); len(herrs) > 0 {
+			for _, err := range herrs {
+				log.Println("Error:", err)
+				errs = append(errs, err)
+			}
+		}
+		if cerrs := r.Connections().Finalize(); len(cerrs) > 0 {
+			for _, err := range cerrs {
+				log.Println("Error:", err)
+				errs = append(errs, err)
+			}
+		}
 	})
+	return errs
 }
 
 // Robots fetch all robots associated with this Gobot instance.

platforms/ardrone/ardrone_adaptor.go

@@ -5,6 +5,8 @@ import (
 	"github.com/hybridgroup/gobot"
 )
 
+var _ gobot.AdaptorInterface = (*ArdroneAdaptor)(nil)
+
 // drone defines expected drone behaviour
 type drone interface {
 	Takeoff() bool
@@ -23,7 +25,7 @@ type drone interface {
 type ArdroneAdaptor struct {
 	gobot.Adaptor
 	drone   drone
-	connect func(*ArdroneAdaptor)
+	connect func(*ArdroneAdaptor) (err error)
 }
 
 // NewArdroneAdaptor creates a new ardrone and connects with default configuration
@@ -33,27 +35,30 @@ func NewArdroneAdaptor(name string, v ...string) *ArdroneAdaptor {
 			name,
 			"ArdroneAdaptor",
 		),
-		connect: func(a *ArdroneAdaptor) {
+		connect: func(a *ArdroneAdaptor) (err error) {
 			config := client.DefaultConfig()
 			if len(v) > 0 {
 				config.Ip = v[0]
 			}
 			d, err := client.Connect(config)
 			if err != nil {
-				panic(err)
+				return
 			}
 			a.drone = d
+			return
 		},
 	}
 }
 
 // Connect returns true when connection to ardrone is established correclty
-func (a *ArdroneAdaptor) Connect() bool {
-	a.connect(a)
-	return true
+func (a *ArdroneAdaptor) Connect() (errs []error) {
+	if err := a.connect(a); err != nil {
+		return []error{err}
+	}
+	return
 }
 
 // Finalize returns true when connection is finalized correctly
-func (a *ArdroneAdaptor) Finalize() bool {
-	return true
+func (a *ArdroneAdaptor) Finalize() (errs []error) {
+	return
 }

platforms/ardrone/ardrone_adaptor_test.go

@@ -7,18 +7,19 @@ import (
 
 func initTestArdroneAdaptor() *ArdroneAdaptor {
 	a := NewArdroneAdaptor("drone")
-	a.connect = func(a *ArdroneAdaptor) {
+	a.connect = func(a *ArdroneAdaptor) error {
 		a.drone = &testDrone{}
+		return nil
 	}
 	return a
 }
 
 func TestConnect(t *testing.T) {
 	a := initTestArdroneAdaptor()
-	gobot.Assert(t, a.Connect(), true)
+	gobot.Assert(t, len(a.Connect()), 0)
 }
 
 func TestFinalize(t *testing.T) {
 	a := initTestArdroneAdaptor()
-	gobot.Assert(t, a.Finalize(), true)
+	gobot.Assert(t, len(a.Finalize()), 0)
 }

platforms/ardrone/ardrone_driver.go

@@ -4,6 +4,8 @@ import (
 	"github.com/hybridgroup/gobot"
 )
 
+var _ gobot.DriverInterface = (*ArdroneDriver)(nil)
+
 type ArdroneDriver struct {
 	gobot.Driver
 }
@@ -30,13 +32,13 @@ func (a *ArdroneDriver) adaptor() *ArdroneAdaptor {
 }
 
 // Start returns true if driver is started succesfully
-func (a *ArdroneDriver) Start() bool {
-	return true
+func (a *ArdroneDriver) Start() (errs []error) {
+	return
 }
 
 // Halt returns true if driver is halted succesfully
-func (a *ArdroneDriver) Halt() bool {
-	return true
+func (a *ArdroneDriver) Halt() (errs []error) {
+	return
 }
 
 // TakeOff makes the drone start flying

platforms/ardrone/ardrone_driver_test.go

@@ -7,8 +7,9 @@ import (
 
 func initTestArdroneDriver() *ArdroneDriver {
 	a := NewArdroneAdaptor("drone")
-	a.connect = func(a *ArdroneAdaptor) {
+	a.connect = func(a *ArdroneAdaptor) (err error) {
 		a.drone = &testDrone{}
+		return
 	}
 	d := NewArdroneDriver(a, "drone")
 	a.Connect()
@@ -17,12 +18,12 @@ func initTestArdroneDriver() *ArdroneDriver {
 
 func TestArdroneDriverStart(t *testing.T) {
 	d := initTestArdroneDriver()
-	gobot.Assert(t, d.Start(), true)
+	gobot.Assert(t, len(d.Start()), 0)
 }
 
 func TestArdroneDriverHalt(t *testing.T) {
 	d := initTestArdroneDriver()
-	gobot.Assert(t, d.Halt(), true)
+	gobot.Assert(t, len(d.Halt()), 0)
 }
 func TestArdroneDriverTakeOff(t *testing.T) {
 	d := initTestArdroneDriver()