Enrich system info response with temperature

service/web/cmd/pi-web-agent.go

@@ -8,9 +8,18 @@ import (
 	"encoding/json"
 )
 
-func os_info_handler(w http.ResponseWriter, req *http.Request) {
+type system_info_response struct {
+	OS_Info api.Os_Info_Response
+	Temperature api.Temperature_Response
+}
+
+func system_info_handler(w http.ResponseWriter, req *http.Request) {
 	os_info := api.OS_Info()
-	json.NewEncoder(w).Encode(os_info)
+	temperature := api.Measure_Temperature()
+	json.NewEncoder(w).Encode(system_info_response{
+		os_info,
+		temperature,
+	})
 }
 
 func main() {
@@ -23,7 +32,7 @@ func main() {
 	}
 	// Simple static webserver:
 	http.HandleFunc(api_action_prefix, dummyHandler)
-	http.HandleFunc(api_info_prefix + "os_info", os_info_handler)
+	http.HandleFunc(api_info_prefix + "os_info", system_info_handler)
 	http.Handle("/assets/", http.FileServer(http.Dir("assets")))
 
 	log.Fatal(http.ListenAndServe(":8080", nil))

service/web/internal/system_files.go

@@ -1,5 +1,8 @@
 package shell
+
 import (
+	"strings"
+
 	"github.com/spf13/viper"
 )
 
@@ -10,4 +13,11 @@ func Read_Env_Config(path string, filename string) (*viper.Viper, error) {
 	config.SetConfigName(filename)
 	err := config.ReadInConfig()
 	return config, err
-}
+}
+
+func ReadConfigFromString(content string) (*viper.Viper, error) {
+	config := viper.New()
+	config.SetConfigType("env")
+	err := config.ReadConfig(strings.NewReader(content))
+	return config, err
+}

service/web/pkg/live_info.go

@@ -2,29 +2,54 @@ package api
 
 import (
 	"log"
+
 	shell "github.com/vaslabs/pi-web-agent/internal"
 )
 
-type os_info_response struct {
+type Os_Info_Response struct {
 	Id               string ""
 	Version_Id       string ""
 	Version_Codename string ""
 }
 
-func OS_Info() os_info_response {
+func OS_Info() Os_Info_Response {
 	return OS_Info_From("/etc", "os-release")
 }
 
-func OS_Info_From(path string, filename string) os_info_response {
+func OS_Info_From(path string, filename string) Os_Info_Response {
 	config, err := shell.Read_Env_Config(path, filename)
 	if err != nil {
 		log.Fatalf("Error %s", err.Error())
-		return os_info_response{}
+		return Os_Info_Response{}
 	} else {
-		return os_info_response{
+		return Os_Info_Response{
 			config.GetString("ID"),
 			config.GetString("VERSION_ID"),
 			config.GetString("VERSION_CODENAME"),
 		}
 	}
 }
+
+type Temperature_Response struct {
+	Temp string
+}
+
+func Measure_Temperature() Temperature_Response {
+	return Measure_Temperature_From("/opt/vc/bin/vcgencmd", "measure_temp")
+}
+
+func Measure_Temperature_From(command string, args ...string) Temperature_Response {
+	output, error := shell.RunSingle(command, args...)
+	if error != nil {
+		log.Fatalf("Error while measuring temperature: %s", error.Error())
+		return Temperature_Response{"unknown"}
+	} else {
+		config, err := shell.ReadConfigFromString(output)
+		if err != nil {
+			log.Fatalf("Error reading temperature output %s", err.Error())
+			return Temperature_Response{"unknown"}
+		} else {
+			return Temperature_Response{config.GetString("temp")}
+		}
+	}
+}

service/web/test/os_info_test.go

@@ -15,6 +15,14 @@ func TestOsReleaseParsing(t *testing.T) {
 	}
 }
 
+func TestTempMeasure(t *testing.T) {
+	expectedTemp := "49.2'C"
+	temperature := api.Measure_Temperature_From("echo", "temp=49.2'C")
+	if (temperature.Temp != expectedTemp) {
+		expectationFailure(expectedTemp, temperature.Temp, t)
+	}
+}
+
 func expectationFailure(expected string, got string, t *testing.T) {
 	t.Errorf("Expected %s but got %s", expected, got)
-}
+}