Chore: a bit of spring cleaning (#16710)

* Chore: use early return technic everywhere

And enable "indent-error-flow" revive rule

* Chore: remove if-return rule from revive config

* Chore: improve error messages

And enable "error-strings" revive rule

* Chore: enable "error-naming" revive rule

* Chore: make linter happy

* Chore: do not duplicate gofmt execution

* Chore: make linter happy

* Chore: address the pull review comments

pkg/models/alert.go

@@ -1,9 +1,8 @@
 package models
 
 import (
-	"time"
-
 	"fmt"
+	"time"
 
 	"github.com/grafana/grafana/pkg/components/simplejson"
 )
@@ -36,7 +35,7 @@ const (
 
 var (
 	ErrCannotChangeStateOnPausedAlert = fmt.Errorf("Cannot change state on pause alert")
-	ErrRequiresNewState               = fmt.Errorf("update alert state requires a new state.")
+	ErrRequiresNewState               = fmt.Errorf("update alert state requires a new state")
 )
 
 func (s AlertStateType) IsValid() bool {

pkg/models/alert_notifications.go

@@ -11,7 +11,7 @@ var (
 	ErrNotificationFrequencyNotFound            = errors.New("Notification frequency not specified")
 	ErrAlertNotificationStateNotFound           = errors.New("alert notification state not found")
 	ErrAlertNotificationStateVersionConflict    = errors.New("alert notification state update version conflict")
-	ErrAlertNotificationStateAlreadyExist       = errors.New("alert notification state already exists.")
+	ErrAlertNotificationStateAlreadyExist       = errors.New("alert notification state already exists")
 	ErrAlertNotificationFailedGenerateUniqueUid = errors.New("Failed to generate unique alert notification uid")
 )
 

pkg/models/dashboard_acl.go

@@ -24,10 +24,10 @@ func (p PermissionType) String() string {
 
 // Typed errors
 var (
-	ErrDashboardAclInfoMissing           = errors.New("User id and team id cannot both be empty for a dashboard permission.")
-	ErrDashboardPermissionDashboardEmpty = errors.New("Dashboard Id must be greater than zero for a dashboard permission.")
-	ErrFolderAclInfoMissing              = errors.New("User id and team id cannot both be empty for a folder permission.")
-	ErrFolderPermissionFolderEmpty       = errors.New("Folder Id must be greater than zero for a folder permission.")
+	ErrDashboardAclInfoMissing           = errors.New("User id and team id cannot both be empty for a dashboard permission")
+	ErrDashboardPermissionDashboardEmpty = errors.New("Dashboard Id must be greater than zero for a dashboard permission")
+	ErrFolderAclInfoMissing              = errors.New("User id and team id cannot both be empty for a folder permission")
+	ErrFolderPermissionFolderEmpty       = errors.New("Folder Id must be greater than zero for a folder permission")
 )
 
 // Dashboard ACL model

pkg/models/datasource.go

@@ -30,7 +30,7 @@ var (
 	ErrDataSourceNotFound           = errors.New("Data source not found")
 	ErrDataSourceNameExists         = errors.New("Data source with same name already exists")
 	ErrDataSourceUpdatingOldVersion = errors.New("Trying to update old version of datasource")
-	ErrDatasourceIsReadOnly         = errors.New("Data source is readonly. Can only be updated from configuration.")
+	ErrDatasourceIsReadOnly         = errors.New("Data source is readonly. Can only be updated from configuration")
 	ErrDataSourceAccessDenied       = errors.New("Data source access denied")
 )
 

pkg/models/notifications.go

@@ -3,7 +3,7 @@ package models
 import "errors"
 
 var ErrInvalidEmailCode = errors.New("Invalid or expired email code")
-var ErrSmtpNotEnabled = errors.New("SMTP not configured, check your grafana.ini config file's [smtp] section.")
+var ErrSmtpNotEnabled = errors.New("SMTP not configured, check your grafana.ini config file's [smtp] section")
 
 type SendEmailCommand struct {
 	To           []string