Improve error handling

cmd/clientFunc.go

@@ -77,7 +77,7 @@ func getJSON(codPostal string) (s string, err error) {
 	client := &http.Client{}
 	req, err := http.NewRequest("GET", "https://www.aemet.es/xml/municipios/localidad_"+codPostal+".xml", nil)
 	if err != nil {
-		e := fmt.Errorf("Error occurred pulling data: %v\n", err)
+		e := fmt.Errorf("Error occurred creating GET request: %v\n", err)
 		return "", e
 	}
 	req.Header.Set("User-Agent", "AEMET-Client/1.0 (https://git.bulgariu.xyz/raul/aemet)")
@@ -85,7 +85,7 @@ func getJSON(codPostal string) (s string, err error) {
 	resp, err := client.Do(req)
 
 	if err != nil {
-		e := fmt.Errorf("Error occurred pulling data: %v\n", err)
+		e := fmt.Errorf("Error occurred executing GET request: %v\n", err)
 		return "", e
 	}
 

cmd/serverFunc.go

@@ -34,14 +34,6 @@ func returnWeather(c *gin.Context) {
 	codPostal := c.Param("localidad")
 	numDias := c.Param("dia")
 
-	if numDias != "" {
-		n, err = strconv.Atoi(numDias)
-		if err != nil {
-			c.String(http.StatusNotAcceptable, "Invalid day identifier")
-			return
-		}
-	}
-
 	isAvailable := false
 	for k := range localidades {
 		if codPostal == k {
@@ -67,6 +59,14 @@ func returnWeather(c *gin.Context) {
 		return
 	}
 
+	if numDias != "" {
+		n, err = strconv.Atoi(numDias)
+		if err != nil || n > len(aemetRequest.Base.Prediccion.Dia)-1 || n < 0 {
+			c.String(http.StatusNotAcceptable, "Invalid day identifier")
+			return
+		}
+	}
+
 	if numDias != "" {
 		c.IndentedJSON(http.StatusOK, aemetRequest.Base.Prediccion.Dia[n])
 	} else {