Add etcd part of config support, add noColor/json support (#8439)

- Add color/json mode support for get/help commands
- Support ENV help for all sub-systems
- Add support for etcd as part of config

pkg/madmin/parse-kv.go

@@ -0,0 +1,156 @@
+/*
+ * MinIO Cloud Storage, (C) 2019 MinIO, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package madmin
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/base64"
+	"fmt"
+	"strings"
+
+	"github.com/minio/minio/pkg/color"
+)
+
+// KVS each sub-system key, value
+type KVS map[string]string
+
+// Targets sub-system targets
+type Targets map[string]map[string]KVS
+
+const (
+	commentKey = "comment"
+)
+
+func (t Targets) String() string {
+	var s strings.Builder
+	for subSys, targetKV := range t {
+		for target, kv := range targetKV {
+			c := kv[commentKey]
+			data, err := base64.RawStdEncoding.DecodeString(c)
+			if err == nil {
+				c = string(data)
+			}
+			for _, c1 := range strings.Split(c, KvNewline) {
+				if c1 == "" {
+					continue
+				}
+				s.WriteString(color.YellowBold(KvComment))
+				s.WriteString(KvSpaceSeparator)
+				s.WriteString(color.BlueBold(strings.TrimSpace(c1)))
+				s.WriteString(KvNewline)
+			}
+			s.WriteString(subSys)
+			if target != Default {
+				s.WriteString(SubSystemSeparator)
+				s.WriteString(target)
+			}
+			s.WriteString(KvSpaceSeparator)
+			for k, v := range kv {
+				// Comment is already printed, do not print it here.
+				if k == commentKey {
+					continue
+				}
+				s.WriteString(k)
+				s.WriteString(KvSeparator)
+				s.WriteString(KvDoubleQuote)
+				s.WriteString(v)
+				s.WriteString(KvDoubleQuote)
+				s.WriteString(KvSpaceSeparator)
+			}
+			if len(t) > 1 {
+				s.WriteString(KvNewline)
+				s.WriteString(KvNewline)
+			}
+		}
+	}
+	return s.String()
+}
+
+// Constant separators
+const (
+	SubSystemSeparator = `:`
+	KvSeparator        = `=`
+	KvSpaceSeparator   = ` `
+	KvComment          = `#`
+	KvDoubleQuote      = `"`
+	KvSingleQuote      = `'`
+
+	KvNewline = "\n"
+	Default   = `_`
+)
+
+// This function is needed, to trim off single or double quotes, creeping into the values.
+func sanitizeValue(v string) string {
+	v = strings.TrimSuffix(strings.TrimPrefix(strings.TrimSpace(v), KvDoubleQuote), KvDoubleQuote)
+	return strings.TrimSuffix(strings.TrimPrefix(v, KvSingleQuote), KvSingleQuote)
+}
+
+func convertTargets(s string, targets Targets) error {
+	inputs := strings.SplitN(s, KvSpaceSeparator, 2)
+	if len(inputs) <= 1 {
+		return fmt.Errorf("invalid number of arguments '%s'", s)
+	}
+	subSystemValue := strings.SplitN(inputs[0], SubSystemSeparator, 2)
+	if len(subSystemValue) == 0 {
+		return fmt.Errorf("invalid number of arguments %s", s)
+	}
+	var kvs = KVS{}
+	var prevK string
+	for _, v := range strings.Fields(inputs[1]) {
+		kv := strings.SplitN(v, KvSeparator, 2)
+		if len(kv) == 0 {
+			continue
+		}
+		if len(kv) == 1 && prevK != "" {
+			kvs[prevK] = strings.Join([]string{kvs[prevK], sanitizeValue(kv[0])}, KvSpaceSeparator)
+			continue
+		}
+		if len(kv[1]) == 0 {
+			return fmt.Errorf("value for key '%s' cannot be empty", kv[0])
+		}
+		prevK = kv[0]
+		kvs[kv[0]] = sanitizeValue(kv[1])
+	}
+
+	_, ok := targets[subSystemValue[0]]
+	if !ok {
+		targets[subSystemValue[0]] = map[string]KVS{}
+	}
+	if len(subSystemValue) == 2 {
+		targets[subSystemValue[0]][subSystemValue[1]] = kvs
+	} else {
+		targets[subSystemValue[0]][Default] = kvs
+	}
+	return nil
+}
+
+// parseSubSysTarget - parse sub-system target
+func parseSubSysTarget(buf []byte) (Targets, error) {
+	targets := make(map[string]map[string]KVS)
+	bio := bufio.NewScanner(bytes.NewReader(buf))
+	for bio.Scan() {
+		if err := convertTargets(bio.Text(), targets); err != nil {
+			return nil, err
+		}
+	}
+	if err := bio.Err(); err != nil {
+		return nil, err
+	}
+	return targets, nil
+}