cmd/storj-sim: add -failfast

Fail all the processes immediately when one of the processes fails. This
is to make it more obvious that one of them has failed.

To disable failfast, use `-failfast=false`.

Change-Id: I2bbedf12fb653e42739d00273aa9ae515d34eda6

cmd/storj-sim/main.go

@@ -25,7 +25,8 @@ type Flags struct {
 	StorageNodeCount int
 	Identities       int
 
-	IsDev bool
+	IsDev    bool
+	FailFast bool
 
 	OnlyEnv bool // only do things necessary for loading env vars
 
@@ -65,6 +66,7 @@ func main() {
 
 	rootCmd.PersistentFlags().BoolVarP(&printCommands, "print-commands", "x", false, "print commands as they are run")
 	rootCmd.PersistentFlags().BoolVarP(&flags.IsDev, "dev", "", true, "use configuration values tuned for development")
+	rootCmd.PersistentFlags().BoolVarP(&flags.FailFast, "failfast", "", true, "stop all processes when one of the processes fails")
 
 	rootCmd.PersistentFlags().StringVarP(&flags.Postgres, "postgres", "", os.Getenv("STORJ_SIM_POSTGRES"), "connection string for postgres (defaults to STORJ_SIM_POSTGRES)")
 	rootCmd.PersistentFlags().StringVarP(&flags.Redis, "redis", "", os.Getenv("STORJ_SIM_REDIS"), "connection string for redis e.g. 127.0.0.1:6379 (defaults to STORJ_SIM_REDIS)")

cmd/storj-sim/network.go

@@ -169,8 +169,14 @@ func networkTest(flags *Flags, command string, args []string) error {
 
 	ctx, cancel := NewCLIContext(context.Background())
 
-	var group errgroup.Group
-	processes.Start(ctx, &group, "run")
+	var group *errgroup.Group
+	if processes.FailFast {
+		group, ctx = errgroup.WithContext(ctx)
+	} else {
+		group = &errgroup.Group{}
+	}
+
+	processes.Start(ctx, group, "run")
 
 	for _, process := range processes.List {
 		process.Status.Started.Wait(ctx)
@@ -230,7 +236,7 @@ func newNetwork(flags *Flags) (*Processes, error) {
 		return all
 	}
 
-	processes := NewProcesses(flags.Directory)
+	processes := NewProcesses(flags.Directory, flags.FailFast)
 
 	var host = flags.Host
 	versioncontrol := processes.New(Info{
@@ -644,7 +650,7 @@ func newNetwork(flags *Flags) (*Processes, error) {
 }
 
 func identitySetup(network *Processes) (*Processes, error) {
-	processes := NewProcesses(network.Directory)
+	processes := NewProcesses(network.Directory, network.FailFast)
 
 	for _, process := range network.List {
 		if process.Info.Executable == "gateway" || process.Info.Executable == "redis-server" {

cmd/storj-sim/process.go

@@ -29,25 +29,33 @@ type Processes struct {
 	Directory string
 	List      []*Process
 
+	FailFast       bool
 	MaxStartupWait time.Duration
 }
 
 const storjSimMaxLineLen = 10000
 
 // NewProcesses returns a group of processes.
-func NewProcesses(dir string) *Processes {
+func NewProcesses(dir string, failfast bool) *Processes {
 	return &Processes{
-		Output:         NewPrefixWriter("sim", storjSimMaxLineLen, os.Stdout),
-		Directory:      dir,
-		List:           nil,
+		Output:    NewPrefixWriter("sim", storjSimMaxLineLen, os.Stdout),
+		Directory: dir,
+		List:      nil,
+
+		FailFast:       failfast,
 		MaxStartupWait: time.Minute,
 	}
 }
 
 // Exec executes a command on all processes.
 func (processes *Processes) Exec(ctx context.Context, command string) error {
-	var group errgroup.Group
-	processes.Start(ctx, &group, command)
+	var group *errgroup.Group
+	if processes.FailFast {
+		group, ctx = errgroup.WithContext(ctx)
+	} else {
+		group = &errgroup.Group{}
+	}
+	processes.Start(ctx, group, command)
 	return group.Wait()
 }