all: uninstall service if got invalid config from API

cmd/ctrld/cli.go

@@ -348,7 +348,7 @@ func readConfigFile(writeDefaultConfig bool) bool {
 	// If err == nil, there's a config supplied via `--config`, no default config written.
 	err := v.ReadInConfig()
 	if err == nil {
-		fmt.Println("loading config file from: ", v.ConfigFileUsed())
+		fmt.Println("loading config file from:", v.ConfigFileUsed())
 		return true
 	}
 
@@ -419,8 +419,21 @@ func processCDFlags() {
 		return
 	}
 	resolverConfig, err := controld.FetchResolverConfig(cdUID)
+	if uer, ok := err.(*controld.UtilityErrorResponse); ok && uer.ErrorField.Code == controld.InvalidConfigCode {
+		s, err := service.New(&prog{}, svcConfig)
+		if err != nil {
+			stderrMsg(err.Error())
+			return
+		}
+		tasks := []task{{s.Uninstall, true}}
+		if doTasks(tasks) {
+			log.Println("uninstalled service")
+		}
+		log.Fatalf("failed to fetch resolver config: %v", uer)
+	}
 	if err != nil {
-		log.Fatalf("failed to fetch resolver config: %v", err)
+		log.Printf("could not fetch resolver config: %v", err)
+		return
 	}
 
 	cfg = ctrld.Config{}

internal/controld/config.go

@@ -3,13 +3,15 @@ package controld
 import (
 	"bytes"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"net/http"
 	"time"
 )
 
-const resolverDataURL = "https://api.controld.com/utility"
+const (
+	resolverDataURL   = "https://api.controld.com/utility"
+	InvalidConfigCode = 40401
+)
 
 // ResolverConfig represents Control D resolver data.
 type ResolverConfig struct {
@@ -24,12 +26,17 @@ type utilityResponse struct {
 	} `json:"body"`
 }
 
-type utilityErrorResponse struct {
-	Error struct {
+type UtilityErrorResponse struct {
+	ErrorField struct {
 		Message string `json:"message"`
+		Code    int    `json:"code"`
 	} `json:"error"`
 }
 
+func (u UtilityErrorResponse) Error() string {
+	return u.ErrorField.Message
+}
+
 type utilityRequest struct {
 	UID string `json:"uid"`
 }
@@ -53,11 +60,11 @@ func FetchResolverConfig(uid string) (*ResolverConfig, error) {
 	defer resp.Body.Close()
 	d := json.NewDecoder(resp.Body)
 	if resp.StatusCode != http.StatusOK {
-		errResp := &utilityErrorResponse{}
+		errResp := &UtilityErrorResponse{}
 		if err := d.Decode(errResp); err != nil {
 			return nil, err
 		}
-		return nil, errors.New(errResp.Error.Message)
+		return nil, errResp
 	}
 
 	ur := &utilityResponse{}