feat: add json colored formatter (#25)

Author: eynopv

pkg/printer/formatter.go

@@ -1,10 +1,10 @@
 package printer
 
 import (
-	"encoding/json"
 	"fmt"
 	"net/http"
 	"sort"
+	"strconv"
 	"strings"
 	"time"
 
@@ -28,7 +28,7 @@ func (f Formatter) RequestLine(line result.RequestLine) string {
 }
 
 func (f Formatter) Json(j map[string]any) string {
-	return formatJson(j)
+	return formatJson(j, f.colored)
 }
 
 func formatHeaders(headers http.Header, colorized bool) string {
@@ -113,10 +113,128 @@ func formatRequestLine(line result.RequestLine, colorized bool) string {
 	return fmt.Sprintf(fstring, Colorize(line.Method, methodColor), line.Url, line.Protocol)
 }
 
-func formatJson(j map[string]any) string {
-	if prettyJson, err := json.MarshalIndent(j, "", "  "); err != nil {
-		return fmt.Sprintf("unable to parse json: %v\n", err)
-	} else {
-		return string(prettyJson)
+func formatJson(j map[string]any, colorized bool) string {
+	var f func(inner map[string]any, level int) string
+
+	var formatValue func(value any, level int) string
+
+	f = func(inner map[string]any, level int) string {
+		sb := strings.Builder{}
+		sb.WriteString("{")
+
+		keys := []string{}
+		for k := range inner {
+			keys = append(keys, k)
+		}
+
+		sort.Strings(keys)
+
+		padding := strings.Repeat("  ", level+1)
+
+		for i, k := range keys {
+			sb.WriteString("\n")
+
+			value := inner[k]
+			isLast := i == len(keys)-1
+
+			sb.WriteString(padding)
+			sb.WriteString(formatJsonKey(k, colorized))
+
+			sb.WriteString(formatValue(value, level))
+
+			if !isLast {
+				sb.WriteString(",")
+			} else {
+				sb.WriteString("\n")
+			}
+		}
+
+		padding = strings.Repeat("  ", level)
+		if sb.Len() != 1 {
+			sb.WriteString(padding)
+		}
+
+		sb.WriteString("}")
+
+		return sb.String()
+	}
+
+	formatValue = func(value any, level int) string {
+		switch v := value.(type) {
+		case string:
+			return formatJsonStringValue(v, colorized)
+		case int, float64:
+			return formatJsonNumberValue(v, colorized)
+		case bool:
+			return formatJsonBoolValue(v, colorized)
+		case nil:
+			return formatJsonNilValue(colorized)
+		case map[string]any:
+			return f(v, level+1)
+		case []any:
+			sb := strings.Builder{}
+			sb.WriteString("[")
+
+			for i, vv := range v {
+				sb.WriteString(formatValue(vv, level))
+
+				if i != len(v)-1 {
+					sb.WriteString(", ")
+				}
+			}
+
+			sb.WriteString("]")
+
+			return sb.String()
+		}
+
+		return ""
 	}
+
+	return f(j, 0)
+}
+
+func formatJsonKey(s string, colorized bool) string {
+	fstring := `%s: `
+	value := strconv.Quote(s)
+
+	if !colorized {
+		return fmt.Sprintf(fstring, value)
+	}
+
+	return fmt.Sprintf(fstring, Yellow(value))
+}
+
+func formatJsonStringValue(s string, colorized bool) string {
+	if !colorized {
+		return strconv.Quote(s)
+	}
+
+	return Green(strconv.Quote(s))
+}
+
+func formatJsonNumberValue(n any, colorized bool) string {
+	s := fmt.Sprintf("%v", n)
+	if !colorized {
+		return s
+	}
+
+	return Cyan(s)
+}
+
+func formatJsonBoolValue(b bool, colorized bool) string {
+	s := fmt.Sprintf("%v", b)
+	if !colorized {
+		return s
+	}
+
+	return Magenta(s)
+}
+
+func formatJsonNilValue(colorized bool) string {
+	if !colorized {
+		return "null"
+	}
+
+	return Red("null")
 }

pkg/printer/formatter_test.go

@@ -174,17 +174,19 @@ func Test_formatRequestLine(t *testing.T) {
 
 func Test_formatJson(t *testing.T) {
 	tests := []struct {
-		name string
-		json map[string]any
-		want string
+		name     string
+		json     map[string]any
+		useColor bool
+		want     string
 	}{
 		{
 			name: "simple",
 			json: map[string]any{
 				"name": "Alice",
 				"age":  30,
 			},
-			want: "{\n  \"age\": 30,\n  \"name\": \"Alice\"\n}",
+			useColor: false,
+			want:     "{\n  \"age\": 30,\n  \"name\": \"Alice\"\n}",
 		},
 		{
 			name: "nested",
@@ -194,25 +196,76 @@ func Test_formatJson(t *testing.T) {
 					"name": "Bob",
 				},
 			},
-			want: "{\n  \"user\": {\n    \"id\": 1,\n    \"name\": \"Bob\"\n  }\n}",
+			useColor: false,
+			want:     "{\n  \"user\": {\n    \"id\": 1,\n    \"name\": \"Bob\"\n  }\n}",
+		},
+		{
+			name:     "empty",
+			json:     map[string]any{},
+			useColor: false,
+			want:     "{}",
+		},
+		{
+			name: "colored int",
+			json: map[string]any{
+				"int": 1,
+			},
+			useColor: true,
+			want:     fmt.Sprintf("{\n  %v: %v\n}", Yellow(`"int"`), Cyan("1")),
+		},
+		{
+			name: "colored string",
+			json: map[string]any{
+				"string": "Hello, World",
+			},
+			useColor: true,
+			want:     fmt.Sprintf("{\n  %v: %v\n}", Yellow(`"string"`), Green(`"Hello, World"`)),
 		},
 		{
-			name: "empty",
-			json: map[string]any{},
-			want: "{}",
+			name: "colored boolean",
+			json: map[string]any{
+				"boolean": true,
+			},
+			useColor: true,
+			want:     fmt.Sprintf("{\n  %v: %v\n}", Yellow(`"boolean"`), Magenta("true")),
 		},
 		{
-			name: "unmarshalable value (channel)",
+			name: "colored float",
 			json: map[string]any{
-				"invalid": make(chan int),
+				"float": 1.23,
 			},
-			want: "unable to parse json: json: unsupported type: chan int\n",
+			useColor: true,
+			want:     fmt.Sprintf("{\n  %v: %v\n}", Yellow(`"float"`), Cyan("1.23")),
+		},
+		{
+			name: "colored nil",
+			json: map[string]any{
+				"nil": nil,
+			},
+			useColor: true,
+			want:     fmt.Sprintf("{\n  %v: %v\n}", Yellow(`"nil"`), Red("null")),
+		},
+		{
+			name: "colored list",
+			json: map[string]any{
+				"list": []any{1, "string", false, nil, map[string]any{"one": 1}},
+			},
+			useColor: true,
+			want: fmt.Sprintf("{\n  %v: [%v, %v, %v, %v, {\n    %v: %v\n  }]\n}",
+				Yellow(`"list"`),
+				Cyan("1"),
+				Green(`"string"`),
+				Magenta("false"),
+				Red("null"),
+				Yellow(`"one"`),
+				Cyan("1"),
+			),
 		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			formatter := Formatter{}
+			formatter := Formatter{colored: tt.useColor}
 			got := formatter.Json(tt.json)
 			assert.Equal(t, tt.want, got)
 		})