Allow providing list of services not to start

changelog/unreleased/exclude-services-option.md

@@ -0,0 +1,7 @@
+Enhancement: Allow providing list of services NOT to start
+
+Until now if one wanted to use a custom version of a service, one
+needed to provide `OCIS_RUN_SERVICES` which is a list of all services to start.
+Now one can provide `OCIS_EXCLUDE_RUN_SERVICES` which is a list of only services not to start
+
+https://github.com/owncloud/ocis/pull/4254

ocis-pkg/config/config.go

@@ -49,7 +49,8 @@ type Mode int
 type Runtime struct {
 	Port       string `yaml:"port" env:"OCIS_RUNTIME_PORT"`
 	Host       string `yaml:"host" env:"OCIS_RUNTIME_HOST"`
-	Extensions string `yaml:"services" env:"OCIS_RUN_EXTENSIONS;OCIS_RUN_SERVICES"`
+	Extensions string `yaml:"services" env:"OCIS_RUN_EXTENSIONS;OCIS_RUN_SERVICES" desc:"Expects a comma separated list of service names. Will start only the listed services."`
+	Disabled   string `yaml:"disabled_services" env:"OCIS_EXCLUDE_RUN_SERVICES" desc:"Expects a comma separated list of service names. Will start all services except of the ones listed. Has no effect when OCIS_RUN_SERVICES is set."`
 }
 
 // Config combines all available configuration parts.

ocis/pkg/runtime/service/service.go

@@ -54,7 +54,7 @@ import (
 
 var (
 	// runset keeps track of which extensions to start supervised.
-	runset []string
+	runset map[string]struct{}
 )
 
 type serviceFuncMap map[string]func(*ociscfg.Config) suture.Service
@@ -227,7 +227,7 @@ func Start(o ...Option) error {
 
 // scheduleServiceTokens adds service tokens to the service supervisor.
 func scheduleServiceTokens(s *Service, funcSet serviceFuncMap) {
-	for _, name := range runset {
+	for name := range runset {
 		if _, ok := funcSet[name]; !ok {
 			continue
 		}
@@ -240,20 +240,28 @@ func scheduleServiceTokens(s *Service, funcSet serviceFuncMap) {
 // generateRunSet interprets the cfg.Runtime.Extensions config option to cherry-pick which services to start using
 // the runtime.
 func (s *Service) generateRunSet(cfg *ociscfg.Config) {
+	runset = make(map[string]struct{})
 	if cfg.Runtime.Extensions != "" {
 		e := strings.Split(strings.ReplaceAll(cfg.Runtime.Extensions, " ", ""), ",")
-		for i := range e {
-			runset = append(runset, e[i])
+		for _, name := range e {
+			runset[name] = struct{}{}
 		}
 		return
 	}
 
 	for name := range s.ServicesRegistry {
-		runset = append(runset, name)
+		runset[name] = struct{}{}
 	}
 
 	for name := range s.Delayed {
-		runset = append(runset, name)
+		runset[name] = struct{}{}
+	}
+
+	if cfg.Runtime.Disabled != "" {
+		e := strings.Split(strings.ReplaceAll(cfg.Runtime.Disabled, " ", ""), ",")
+		for _, name := range e {
+			delete(runset, name)
+		}
 	}
 }