Add log opts flag to pass in logging options

Signed-off-by: wlan0 <sidharthamn@gmail.com>

opts/opts.go

@@ -28,6 +28,14 @@ func ListVar(values *[]string, names []string, usage string) {
 	flag.Var(newListOptsRef(values, nil), names, usage)
 }
 
+func MapVar(values map[string]string, names []string, usage string) {
+	flag.Var(newMapOpt(values, nil), names, usage)
+}
+
+func LogOptsVar(values map[string]string, names []string, usage string) {
+	flag.Var(newMapOpt(values, ValidateLogOpts), names, usage)
+}
+
 func HostListVar(values *[]string, names []string, usage string) {
 	flag.Var(newListOptsRef(values, ValidateHost), names, usage)
 }
@@ -130,10 +138,53 @@ func (opts *ListOpts) Len() int {
 	return len((*opts.values))
 }
 
+//MapOpts type
+type MapOpts struct {
+	values    map[string]string
+	validator ValidatorFctType
+}
+
+func (opts *MapOpts) Set(value string) error {
+	if opts.validator != nil {
+		v, err := opts.validator(value)
+		if err != nil {
+			return err
+		}
+		value = v
+	}
+	vals := strings.SplitN(value, "=", 2)
+	if len(vals) == 1 {
+		(opts.values)[vals[0]] = ""
+	} else {
+		(opts.values)[vals[0]] = vals[1]
+	}
+	return nil
+}
+
+func (opts *MapOpts) String() string {
+	return fmt.Sprintf("%v", map[string]string((opts.values)))
+}
+
+func newMapOpt(values map[string]string, validator ValidatorFctType) *MapOpts {
+	return &MapOpts{
+		values:    values,
+		validator: validator,
+	}
+}
+
 // Validators
 type ValidatorFctType func(val string) (string, error)
 type ValidatorFctListType func(val string) ([]string, error)
 
+func ValidateLogOpts(val string) (string, error) {
+	allowedKeys := map[string]string{}
+	vals := strings.Split(val, "=")
+	if allowedKeys[vals[0]] != "" {
+		return val, nil
+	}
+	return "", fmt.Errorf("%s is not a valid log opt", vals[0])
+}
+
 func ValidateAttach(val string) (string, error) {
 	s := strings.ToLower(val)
 	for _, str := range []string{"stdin", "stdout", "stderr"} {

opts/opts_test.go

@@ -1,6 +1,7 @@
 package opts
 
 import (
+	"fmt"
 	"strings"
 	"testing"
 )
@@ -28,6 +29,31 @@ func TestValidateIPAddress(t *testing.T) {
 
 }
 
+func TestMapOpts(t *testing.T) {
+	tmpMap := make(map[string]string)
+	o := newMapOpt(tmpMap, logOptsValidator)
+	o.Set("max-size=1")
+	if o.String() != "map[max-size:1]" {
+		t.Errorf("%s != [map[max-size:1]", o.String())
+	}
+
+	o.Set("max-file=2")
+	if len(tmpMap) != 2 {
+		t.Errorf("map length %d != 2", len(tmpMap))
+	}
+
+	if tmpMap["max-file"] != "2" {
+		t.Errorf("max-file = %s != 2", tmpMap["max-file"])
+	}
+
+	if tmpMap["max-size"] != "1" {
+		t.Errorf("max-size = %s != 1", tmpMap["max-size"])
+	}
+	if o.Set("dummy-val=3") == nil {
+		t.Errorf("validator is not being called")
+	}
+}
+
 func TestValidateMACAddress(t *testing.T) {
 	if _, err := ValidateMACAddress(`92:d0:c6:0a:29:33`); err != nil {
 		t.Fatalf("ValidateMACAddress(`92:d0:c6:0a:29:33`) got %s", err)
@@ -152,3 +178,12 @@ func TestValidateExtraHosts(t *testing.T) {
 		}
 	}
 }
+
+func logOptsValidator(val string) (string, error) {
+	allowedKeys := map[string]string{"max-size": "1", "max-file": "2"}
+	vals := strings.Split(val, "=")
+	if allowedKeys[vals[0]] != "" {
+		return val, nil
+	}
+	return "", fmt.Errorf("invalid key %s", vals[0])
+}