First commit

core/caddyfile/json.go

@@ -0,0 +1,173 @@
+package caddyfile
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+
+	"github.com/miekg/coredns/core/parse"
+)
+
+const filename = "Caddyfile"
+
+// ToJSON converts caddyfile to its JSON representation.
+func ToJSON(caddyfile []byte) ([]byte, error) {
+	var j Caddyfile
+
+	serverBlocks, err := parse.ServerBlocks(filename, bytes.NewReader(caddyfile), false)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, sb := range serverBlocks {
+		block := ServerBlock{Body: [][]interface{}{}}
+
+		// Fill up host list
+		for _, host := range sb.HostList() {
+			block.Hosts = append(block.Hosts, host)
+		}
+
+		// Extract directives deterministically by sorting them
+		var directives = make([]string, len(sb.Tokens))
+		for dir := range sb.Tokens {
+			directives = append(directives, dir)
+		}
+		sort.Strings(directives)
+
+		// Convert each directive's tokens into our JSON structure
+		for _, dir := range directives {
+			disp := parse.NewDispenserTokens(filename, sb.Tokens[dir])
+			for disp.Next() {
+				block.Body = append(block.Body, constructLine(&disp))
+			}
+		}
+
+		// tack this block onto the end of the list
+		j = append(j, block)
+	}
+
+	result, err := json.Marshal(j)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+// constructLine transforms tokens into a JSON-encodable structure;
+// but only one line at a time, to be used at the top-level of
+// a server block only (where the first token on each line is a
+// directive) - not to be used at any other nesting level.
+func constructLine(d *parse.Dispenser) []interface{} {
+	var args []interface{}
+
+	args = append(args, d.Val())
+
+	for d.NextArg() {
+		if d.Val() == "{" {
+			args = append(args, constructBlock(d))
+			continue
+		}
+		args = append(args, d.Val())
+	}
+
+	return args
+}
+
+// constructBlock recursively processes tokens into a
+// JSON-encodable structure. To be used in a directive's
+// block. Goes to end of block.
+func constructBlock(d *parse.Dispenser) [][]interface{} {
+	block := [][]interface{}{}
+
+	for d.Next() {
+		if d.Val() == "}" {
+			break
+		}
+		block = append(block, constructLine(d))
+	}
+
+	return block
+}
+
+// FromJSON converts JSON-encoded jsonBytes to Caddyfile text
+func FromJSON(jsonBytes []byte) ([]byte, error) {
+	var j Caddyfile
+	var result string
+
+	err := json.Unmarshal(jsonBytes, &j)
+	if err != nil {
+		return nil, err
+	}
+
+	for sbPos, sb := range j {
+		if sbPos > 0 {
+			result += "\n\n"
+		}
+		for i, host := range sb.Hosts {
+			if i > 0 {
+				result += ", "
+			}
+			result += host
+		}
+		result += jsonToText(sb.Body, 1)
+	}
+
+	return []byte(result), nil
+}
+
+// jsonToText recursively transforms a scope of JSON into plain
+// Caddyfile text.
+func jsonToText(scope interface{}, depth int) string {
+	var result string
+
+	switch val := scope.(type) {
+	case string:
+		if strings.ContainsAny(val, "\" \n\t\r") {
+			result += `"` + strings.Replace(val, "\"", "\\\"", -1) + `"`
+		} else {
+			result += val
+		}
+	case int:
+		result += strconv.Itoa(val)
+	case float64:
+		result += fmt.Sprintf("%v", val)
+	case bool:
+		result += fmt.Sprintf("%t", val)
+	case [][]interface{}:
+		result += " {\n"
+		for _, arg := range val {
+			result += strings.Repeat("\t", depth) + jsonToText(arg, depth+1) + "\n"
+		}
+		result += strings.Repeat("\t", depth-1) + "}"
+	case []interface{}:
+		for i, v := range val {
+			if block, ok := v.([]interface{}); ok {
+				result += "{\n"
+				for _, arg := range block {
+					result += strings.Repeat("\t", depth) + jsonToText(arg, depth+1) + "\n"
+				}
+				result += strings.Repeat("\t", depth-1) + "}"
+				continue
+			}
+			result += jsonToText(v, depth)
+			if i < len(val)-1 {
+				result += " "
+			}
+		}
+	}
+
+	return result
+}
+
+// Caddyfile encapsulates a slice of ServerBlocks.
+type Caddyfile []ServerBlock
+
+// ServerBlock represents a server block.
+type ServerBlock struct {
+	Hosts []string        `json:"hosts"`
+	Body  [][]interface{} `json:"body"`
+}