[FAB-1653] Enable human-readable byte sizes in config

Byte sizes can be specified with the following case
insensitive suffixes:
 - 'k', 'kb', 'm', 'mb', 'g', 'gb'

Change-Id: I36c3fd424ed52794562a6b50e7a3d400f053c52a
Signed-off-by: Luis Sanchez <sanchezl@us.ibm.com>

orderer/localconfig/config_test.go

@@ -93,6 +93,77 @@ func TestEnvSlice(t *testing.T) {
 	}
 }
 
+type testByteSize struct {
+	Inner struct {
+		ByteSize uint32
+	}
+}
+
+func TestByteSize(t *testing.T) {
+	config := viper.New()
+	config.SetConfigType("yaml")
+
+	testCases := []struct {
+		data     string
+		expected uint32
+	}{
+		{"", 0},
+		{"42", 42},
+		{"42k", 42 * 1024},
+		{"42kb", 42 * 1024},
+		{"42K", 42 * 1024},
+		{"42KB", 42 * 1024},
+		{"42 K", 42 * 1024},
+		{"42 KB", 42 * 1024},
+		{"42m", 42 * 1024 * 1024},
+		{"42mb", 42 * 1024 * 1024},
+		{"42M", 42 * 1024 * 1024},
+		{"42MB", 42 * 1024 * 1024},
+		{"42 M", 42 * 1024 * 1024},
+		{"42 MB", 42 * 1024 * 1024},
+		{"3g", 3 * 1024 * 1024 * 1024},
+		{"3gb", 3 * 1024 * 1024 * 1024},
+		{"3G", 3 * 1024 * 1024 * 1024},
+		{"3GB", 3 * 1024 * 1024 * 1024},
+		{"3 G", 3 * 1024 * 1024 * 1024},
+		{"3 GB", 3 * 1024 * 1024 * 1024},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.data, func(t *testing.T) {
+			data := fmt.Sprintf("---\nInner:\n    ByteSize: %s", tc.data)
+			err := config.ReadConfig(bytes.NewReader([]byte(data)))
+			if err != nil {
+				t.Fatalf("Error reading config: %s", err)
+			}
+			var uconf testByteSize
+			err = ExactWithDateUnmarshal(config, &uconf)
+			if err != nil {
+				t.Fatalf("Failed to unmarshal with: %s", err)
+			}
+			if uconf.Inner.ByteSize != tc.expected {
+				t.Fatalf("Did not get back the right byte size, expeced: %v got %v", tc.expected, uconf.Inner.ByteSize)
+			}
+		})
+	}
+}
+
+func TestByteSizeOverflow(t *testing.T) {
+	config := viper.New()
+	config.SetConfigType("yaml")
+
+	data := "---\nInner:\n    ByteSize: 4GB"
+	err := config.ReadConfig(bytes.NewReader([]byte(data)))
+	if err != nil {
+		t.Fatalf("Error reading config: %s", err)
+	}
+	var uconf testByteSize
+	err = ExactWithDateUnmarshal(config, &uconf)
+	if err == nil {
+		t.Fatalf("Should have failed to unmarshal")
+	}
+}
+
 // TestEnvInnerVar verifies that with the Unmarshal function that
 // the environmental overrides still work on internal vars.  This was
 // a bug in the original viper implementation that is worked around in

orderer/localconfig/config_util.go

@@ -17,7 +17,11 @@ limitations under the License.
 package config
 
 import (
+	"fmt"
+	"math"
 	"reflect"
+	"regexp"
+	"strconv"
 	"strings"
 	"time"
 
@@ -83,6 +87,41 @@ func customDecodeHook() mapstructure.DecodeHookFunc {
 	}
 }
 
+func byteSizeDecodeHook() mapstructure.DecodeHookFunc {
+	return func(f reflect.Kind, t reflect.Kind, data interface{}) (interface{}, error) {
+		if f != reflect.String || t != reflect.Uint32 {
+			return data, nil
+		}
+		raw := data.(string)
+		if raw == "" {
+			return data, nil
+		}
+		var re = regexp.MustCompile(`^(?P<size>[0-9]+)\s*(?i)(?P<unit>(k|m|g))b?$`)
+		if re.MatchString(raw) {
+			size, err := strconv.ParseUint(re.ReplaceAllString(raw, "${size}"), 0, 64)
+			if err != nil {
+				return data, nil
+			}
+			unit := re.ReplaceAllString(raw, "${unit}")
+			switch strings.ToLower(unit) {
+			case "g":
+				size = size << 10
+				fallthrough
+			case "m":
+				size = size << 10
+				fallthrough
+			case "k":
+				size = size << 10
+			}
+			if size > math.MaxUint32 {
+				return size, fmt.Errorf("value '%s' overflows uint32", raw)
+			}
+			return size, nil
+		}
+		return data, nil
+	}
+}
+
 // ExactWithDateUnmarshal is intended to unmarshal a config file into a structure
 // producing error when extraneous variables are introduced and supporting
 // the time.Duration type
@@ -96,7 +135,10 @@ func ExactWithDateUnmarshal(v *viper.Viper, output interface{}) error {
 		Metadata:         nil,
 		Result:           output,
 		WeaklyTypedInput: true,
-		DecodeHook:       customDecodeHook(),
+		DecodeHook: mapstructure.ComposeDecodeHookFunc(
+			customDecodeHook(),
+			byteSizeDecodeHook(),
+		),
 	}
 
 	decoder, err := mapstructure.NewDecoder(config)

orderer/orderer.yaml

@@ -124,9 +124,9 @@ Genesis:
 
         # Absolute Max Bytes: The absolute maximum number of bytes allowed for
         # the serialized messages in a batch.
-        AbsoluteMaxBytes: 100000000
+        AbsoluteMaxBytes: 99 MB
 
         # Preferred Max Bytes: The preferred maximum number of bytes allowed for
         # the serialized messages in a batch. A message larger than the preferred
         # max bytes will result in a batch larger than preferred max bytes.
-        PreferredMaxBytes: 524288
+        PreferredMaxBytes: 512 KB