Adding Function methods to spark core adaptor

examples/spark_core_function.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/hybridgroup/gobot"
+	"github.com/hybridgroup/gobot/platforms/spark"
+)
+
+func main() {
+	gbot := gobot.NewGobot()
+
+	sparkCore := spark.NewSparkCoreAdaptor("spark", "DEVICE_ID", "ACCESS_TOKEN")
+
+	work := func() {
+		result, err := sparkCore.Function("brew", "hello")
+
+		if err != nil {
+			fmt.Println(err.Error())
+		} else {
+			fmt.Printf("result from executing function is: %v", result)
+		}
+	}
+
+	robot := gobot.NewRobot("spark",
+		[]gobot.Connection{sparkCore},
+		[]gobot.Device{},
+		work,
+	)
+
+	gbot.AddRobot(robot)
+
+	gbot.Start()
+}

examples/spark_core_variable.go

@@ -10,7 +10,7 @@ import (
 func main() {
 	gbot := gobot.NewGobot()
 
-	sparkCore := spark.NewSparkCoreAdaptor("spark", "53ff72065067544846101187", "f7e2983869e725addd416270cb055ba04a33fdad")
+	sparkCore := spark.NewSparkCoreAdaptor("spark", "DEVICE_ID", "ACCESS_TOKEN")
 
 	work := func() {
 		temp, err := sparkCore.Variable("temperature")

platforms/spark/spark_core_adaptor.go

@@ -118,6 +118,27 @@ func (s *SparkCoreAdaptor) Variable(name string) (val interface{}, err error) {
 	return
 }
 
+// Function executes a core function and
+// returns value from request.
+// Takes a String as the only argument and returns an Int.
+// If function is not defined in core, it will time out
+func (s *SparkCoreAdaptor) Function(name string, paramString string) (val int, err error) {
+	params := url.Values{
+		"args":         {paramString},
+		"access_token": {s.AccessToken},
+	}
+
+	url := fmt.Sprintf("%s/%s", s.deviceURL(), name)
+	resp, err := s.requestToSpark("POST", url, params)
+
+	if err == nil {
+		val = int(resp["return_value"].(float64))
+		return
+	}
+
+	return -1, err
+}
+
 // setAPIServer sets spark cloud api server, this can be used to change from default api.spark.io
 func (s *SparkCoreAdaptor) setAPIServer(server string) {
 	s.APIServer = server
@@ -163,12 +184,9 @@ func (s *SparkCoreAdaptor) requestToSpark(method string, url string, params url.
 	json.Unmarshal(buf, &m)
 
 	if resp.Status != "200 OK" {
-		if _, ok := m["error"]; ok {
-			err = errors.New(m["error"].(string))
-		} else {
-			err = errors.New(fmt.Sprintf("&v: error communicating to the spark cloud", resp.Status))
-		}
-		return
+		err = errors.New(fmt.Sprintf("&v: error communicating to the spark cloud", resp.Status))
+	} else if _, ok := m["error"]; ok {
+		err = errors.New(m["error"].(string))
 	}
 
 	return

platforms/spark/spark_core_adaptor_test.go

@@ -277,9 +277,9 @@ func TestSparkCoreAdaptorPostToSpark(t *testing.T) {
 	// When error on request
 	vals := url.Values{}
 	vals.Add("error", "error")
-	resp, err := a.postToSpark("http://invalid%20host.com", vals)
+	resp, err := a.requestToSpark("POST", "http://invalid%20host.com", vals)
 	if err == nil {
-		t.Errorf("postToSpark() should return an error when request was unsuccessful but returned", resp)
+		t.Errorf("requestToSpark() should return an error when request was unsuccessful but returned", resp)
 	}
 
 	// When error reading body
@@ -291,9 +291,9 @@ func TestSparkCoreAdaptorPostToSpark(t *testing.T) {
 	})
 	defer testServer.Close()
 
-	resp, err = a.postToSpark(testServer.URL+"/existent", vals)
+	resp, err = a.requestToSpark("POST", testServer.URL+"/existent", vals)
 	if err == nil {
-		t.Errorf("postToSpark() should return an error when status is not 200 but returned", resp)
+		t.Errorf("requestToSpark() should return an error when status is not 200 but returned", resp)
 	}
 
 }