Provide the ability to update configuration via the API

See merge request shouptech/tempgopher!2

config.go

@@ -3,6 +3,9 @@ package main
 import (
 	"errors"
 	"io/ioutil"
+	"log"
+	"os"
+	"syscall"
 
 	"gopkg.in/yaml.v2"
 )
@@ -30,6 +33,64 @@ type Config struct {
 	DisplayFahrenheit bool     `yaml:"displayfahrenheit"`
 }
 
+var configFilePath string
+
+// UpdateSensorConfig updates the configuration of an individual sensor and writes to disk
+func UpdateSensorConfig(s Sensor) error {
+	config, err := LoadConfig(configFilePath)
+	if err != nil {
+		return err
+	}
+
+	for i := range config.Sensors {
+		if config.Sensors[i].ID == s.ID {
+			config.Sensors[i].Alias = s.Alias
+			config.Sensors[i].HighTemp = s.HighTemp
+			config.Sensors[i].LowTemp = s.LowTemp
+			config.Sensors[i].HeatGPIO = s.HeatGPIO
+			config.Sensors[i].HeatInvert = s.HeatInvert
+			config.Sensors[i].HeatMinutes = s.HeatMinutes
+			config.Sensors[i].CoolGPIO = s.CoolGPIO
+			config.Sensors[i].CoolInvert = s.CoolInvert
+			config.Sensors[i].CoolMinutes = s.CoolMinutes
+			config.Sensors[i].Verbose = s.Verbose
+			log.Println(config.Sensors[i])
+		}
+	}
+
+	if err = SaveConfig(configFilePath, *config); err != nil {
+		return err
+	}
+
+	log.Println(config.Sensors[0])
+
+	if err = SignalReload(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// SignalReload sends a SIGHUP to the process, initiating a configuration reload
+func SignalReload() error {
+	p := os.Process{Pid: os.Getpid()}
+	return p.Signal(syscall.SIGHUP)
+}
+
+// SaveConfig will write a new configuration file
+func SaveConfig(path string, config Config) error {
+	d, err := yaml.Marshal(config)
+	if err != nil {
+		return err
+	}
+
+	if err = ioutil.WriteFile(path, d, 0644); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 // LoadConfig will loads a file and parses it into a Config struct
 func LoadConfig(path string) (*Config, error) {
 	data, err := ioutil.ReadFile(path)
@@ -37,6 +98,7 @@ func LoadConfig(path string) (*Config, error) {
 		return nil, err
 	}
 
+	configFilePath = path
 	var config Config
 	yaml.Unmarshal(data, &config)
 

html/js/thermostat.js

@@ -38,9 +38,9 @@ function renderThermostats() {
             var statusdiv = $("<div></div>").addClass("three columns").append(statusp);
             rowdiv.append(statusdiv);
 
-            // Display config
+            // Display sensor config
             $.ajax({
-                url: jsconfig.baseurl + "/api/config/" + data[key].alias
+                url: jsconfig.baseurl + "/api/config/sensors/" + data[key].alias
             }).then(function(configData){
                 if (jsconfig.fahrenheit) {
                     var hightemp = celsiusToFahrenheit(parseFloat(configData.hightemp)).toFixed(1) + "°F";

main.go

@@ -8,7 +8,7 @@ import (
 )
 
 // Version is the current code version of tempgopher
-const Version = "0.1.0"
+const Version = "0.2.0-dev"
 
 func main() {
 	var args struct {

web.go

@@ -14,14 +14,15 @@ import (
 	"github.com/gin-contrib/cors"
 	"github.com/gin-gonic/gin"
 	"github.com/gobuffalo/packr"
+	"github.com/jinzhu/copier"
 )
 
-// PingHandler responds to get requests with the message "pong".
+// PingHandler responds to GET requests with the message "pong".
 func PingHandler(c *gin.Context) {
 	c.String(http.StatusOK, "pong")
 }
 
-// ConfigHandler responds to get requests with the current configuration.
+// ConfigHandler responds to GET requests with the current configuration.
 func ConfigHandler(config *Config) gin.HandlerFunc {
 	fn := func(c *gin.Context) {
 		if c.Param("alias") != "/" && c.Param("alias") != "" {
@@ -34,16 +35,37 @@ func ConfigHandler(config *Config) gin.HandlerFunc {
 				}
 			}
 			if !found {
-				c.String(http.StatusNotFound, "Not found")
+				c.JSON(http.StatusNotFound, gin.H{"error": "Not Found"})
 			}
+		} else if c.Param("alias") == "/" {
+			c.JSON(http.StatusOK, config.Sensors)
 		} else {
-			c.JSON(http.StatusOK, *config)
+			c.JSON(http.StatusOK, config)
 		}
 	}
 	return gin.HandlerFunc(fn)
 }
 
-// StatusHandler responds to get requests with the current status of a sensor
+// UpdateSensorsHandler responds to POST requests by updating the stored configuration and issuing a reload to the app
+func UpdateSensorsHandler(c *gin.Context) {
+	var sensors []Sensor
+
+	if err := c.ShouldBindJSON(&sensors); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+		return
+	}
+
+	for _, s := range sensors {
+		if err := UpdateSensorConfig(s); err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": err})
+			return
+		}
+	}
+
+	c.JSON(http.StatusOK, gin.H{"status": "updated"})
+}
+
+// StatusHandler responds to GET requests with the current status of a sensor
 func StatusHandler(states *map[string]State) gin.HandlerFunc {
 	fn := func(c *gin.Context) {
 		if c.Param("alias") == "/" || c.Param("alias") == "" {
@@ -63,7 +85,7 @@ func GetBox() packr.Box {
 	return packr.NewBox("./html")
 }
 
-// JSConfigHandler responds to get requests with the current configuration for the JS app
+// JSConfigHandler responds to GET requests with the current configuration for the JS app
 func JSConfigHandler(config *Config) gin.HandlerFunc {
 	fn := func(c *gin.Context) {
 		jsconfig := "var jsconfig={baseurl:\"" + config.BaseURL + "\",fahrenheit:" + strconv.FormatBool(config.DisplayFahrenheit) + "};"
@@ -111,7 +133,8 @@ func SetupRouter(config *Config, states *map[string]State) *gin.Engine {
 
 	// Config
 	r.GET("/api/config", ConfigHandler(config))
-	r.GET("/api/config/*alias", ConfigHandler(config))
+	r.GET("/api/config/sensors/*alias", ConfigHandler(config))
+	r.POST("/api/config/sensors", UpdateSensorsHandler)
 
 	// App
 	r.GET("/jsconfig.js", JSConfigHandler(config))
@@ -125,6 +148,18 @@ func SetupRouter(config *Config, states *map[string]State) *gin.Engine {
 	return r
 }
 
+// reloadWebConfig reloads the current copy of configuration
+func reloadWebConfig(c *Config, p string) error {
+	nc, err := LoadConfig(p)
+	if err != nil {
+		return err
+	}
+
+	copier.Copy(&c, &nc)
+
+	return nil
+}
+
 // RunWeb launches a web server. sc is used to update the states from the Thermostats.
 func RunWeb(configpath string, sc <-chan State, wg *sync.WaitGroup) {
 	// Update sensor states when a new state comes back from the thermostat.
@@ -145,7 +180,7 @@ func RunWeb(configpath string, sc <-chan State, wg *sync.WaitGroup) {
 	go func() {
 		for {
 			<-hup
-			config, err = LoadConfig(configpath)
+			err = reloadWebConfig(config, configpath)
 			if err != nil {
 				log.Panicln(err)
 			}