vfs,mount,cmount,mountlib: allow flags to be overriden by environment variables

fs/flags.go

@@ -268,6 +268,14 @@ func StringP(name, shorthand string, value string, usage string) (out *string) {
 	return out
 }
 
+// StringVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.StringVarP
+func StringVarP(flags *pflag.FlagSet, p *string, name, shorthand string, value string, usage string) {
+	flags.StringVarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // BoolP defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.BoolP
@@ -277,6 +285,14 @@ func BoolP(name, shorthand string, value bool, usage string) (out *bool) {
 	return out
 }
 
+// BoolVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.BoolVarP
+func BoolVarP(flags *pflag.FlagSet, p *bool, name, shorthand string, value bool, usage string) {
+	flags.BoolVarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // IntP defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.IntP
@@ -286,6 +302,22 @@ func IntP(name, shorthand string, value int, usage string) (out *int) {
 	return out
 }
 
+// IntVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.IntVarP
+func IntVarP(flags *pflag.FlagSet, p *int, name, shorthand string, value int, usage string) {
+	flags.IntVarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
+// Uint32VarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.Uint32VarP
+func Uint32VarP(flags *pflag.FlagSet, p *uint32, name, shorthand string, value uint32, usage string) {
+	flags.Uint32VarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // Float64P defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.Float64P
@@ -295,6 +327,14 @@ func Float64P(name, shorthand string, value float64, usage string) (out *float64
 	return out
 }
 
+// Float64VarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.Float64VarP
+func Float64VarP(flags *pflag.FlagSet, p *float64, name, shorthand string, value float64, usage string) {
+	flags.Float64VarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // DurationP defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.DurationP
@@ -304,6 +344,14 @@ func DurationP(name, shorthand string, value time.Duration, usage string) (out *
 	return out
 }
 
+// DurationVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.DurationVarP
+func DurationVarP(flags *pflag.FlagSet, p *time.Duration, name, shorthand string, value time.Duration, usage string) {
+	flags.DurationVarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // VarP defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.VarP
@@ -312,6 +360,14 @@ func VarP(value pflag.Value, name, shorthand, usage string) {
 	setDefaultFromEnv(name)
 }
 
+// FlagsVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.VarP
+func FlagsVarP(flags *pflag.FlagSet, value pflag.Value, name, shorthand, usage string) {
+	flags.VarP(value, name, shorthand, usage)
+	setDefaultFromEnv(name)
+}
+
 // StringArrayP defines a flag which can be overridden by an environment variable
 //
 // It sets one value only - command line flags can be used to set more.
@@ -323,6 +379,16 @@ func StringArrayP(name, shorthand string, value []string, usage string) (out *[]
 	return out
 }
 
+// StringArrayVarP defines a flag which can be overridden by an environment variable
+//
+// It sets one value only - command line flags can be used to set more.
+//
+// It is a thin wrapper around pflag.StringArrayVarP
+func StringArrayVarP(flags *pflag.FlagSet, p *[]string, name, shorthand string, value []string, usage string) {
+	flags.StringArrayVarP(p, name, shorthand, value, usage)
+	setDefaultFromEnv(name)
+}
+
 // CountP defines a flag which can be overridden by an environment variable
 //
 // It is a thin wrapper around pflag.CountP
@@ -331,3 +397,11 @@ func CountP(name, shorthand string, usage string) (out *int) {
 	setDefaultFromEnv(name)
 	return out
 }
+
+// CountVarP defines a flag which can be overridden by an environment variable
+//
+// It is a thin wrapper around pflag.CountVarP
+func CountVarP(flags *pflag.FlagSet, p *int, name, shorthand string, usage string) {
+	flags.CountVarP(p, name, shorthand, usage)
+	setDefaultFromEnv(name)
+}