Add go port of jsonpretty

.gitignore

@@ -1,3 +1,5 @@
 *.gem
 pkg
 /Gemfile.lock
+
+dist/

.goreleaser.yaml

@@ -0,0 +1,30 @@
+# This is an example .goreleaser.yml file with some sensible defaults.
+# Make sure to check the documentation at https://goreleaser.com
+before:
+  hooks:
+    # You may remove this if you don't use go modules.
+    - go mod tidy
+builds:
+  - env:
+      - CGO_ENABLED=0
+    goos:
+      - linux
+      - windows
+      - darwin
+archives:
+  - replacements:
+      darwin: Darwin
+      linux: Linux
+      windows: Windows
+      386: i386
+      amd64: x86_64
+checksum:
+  name_template: 'checksums.txt'
+snapshot:
+  name_template: "{{ incpatch .Version }}-next"
+changelog:
+  sort: asc
+  filters:
+    exclude:
+      - '^docs:'
+      - '^test:'

go.mod

@@ -0,0 +1,3 @@
+module github.com/nicksieger/jsonpretty
+
+go 1.17

main.go

@@ -0,0 +1,199 @@
+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"regexp"
+	"strings"
+)
+
+var (
+	version = "dev"
+	commit  = ""
+	date    = ""
+	builtBy = ""
+)
+
+type JsonArg struct {
+	file    *os.File
+	content []byte
+}
+
+func (j JsonArg) Close() error {
+	if j.file != nil {
+		return j.file.Close()
+	}
+	return nil
+}
+
+func usage(code int) {
+	fmt.Printf("usage: %s [args|@filename|@- (stdin)]\n", os.Args[0])
+	fmt.Printf("Parse and pretty-print JSON, either from stdin or from arguments concatenated together\n")
+	os.Exit(code)
+}
+
+func versionInfo() string {
+	if commit != "" && date != "" {
+		return fmt.Sprintf("%s (%s on %s)", version, commit[0:7], date[0:10])
+	}
+	return version
+}
+
+func checkFlags(arg string) {
+	if arg[0] == '-' && len(arg) > 1 {
+		code := 1
+		if arg == "-v" || strings.HasPrefix(arg, "--v") {
+			fmt.Printf("jsonpretty version %s\n", versionInfo())
+			os.Exit(0)
+		} else if arg == "-h" || strings.HasPrefix(arg, "--h") {
+			code = 0
+		}
+		if code == 1 {
+			fmt.Printf("unrecognized flag %s\n", arg)
+		}
+		usage(code)
+	}
+}
+
+func buildJsonSource(args []JsonArg) *bytes.Buffer {
+	buffer := bytes.NewBuffer(nil)
+	for _, arg := range args {
+		if arg.file != nil {
+			_, err := buffer.ReadFrom(arg.file)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "error reading file: %v\n", err)
+			}
+		} else {
+			_, err := buffer.Write(arg.content)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "error appending content: %v\n", err)
+			}
+		}
+	}
+	return buffer
+}
+
+func readArguments(args []string) *bytes.Buffer {
+	jsonArgs := []JsonArg{}
+	defer func() {
+		for _, j := range jsonArgs {
+			_ = j.Close()
+		}
+	}()
+	for _, arg := range args {
+		checkFlags(arg)
+
+		if arg == "-" || arg == "@-" {
+			jsonArgs = append(jsonArgs, JsonArg{file: os.Stdin})
+		} else if strings.HasPrefix(arg, "@") {
+			file, err := os.Open(arg[1:])
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "skipping '%s' due to error: %v\n", arg, err)
+				continue
+			}
+			jsonArgs = append(jsonArgs, JsonArg{file: file})
+		} else {
+			jsonArgs = append(jsonArgs, JsonArg{content: []byte(arg)})
+		}
+	}
+
+	if len(jsonArgs) == 0 {
+		jsonArgs = append(jsonArgs, JsonArg{file: os.Stdin})
+	}
+	return buildJsonSource(jsonArgs)
+}
+
+var httpRegex *regexp.Regexp = regexp.MustCompile("^HTTP/\\d")
+
+func parseHeaders(src *bytes.Buffer) ([]byte, []byte, error) {
+	headerBuffer := bytes.NewBuffer(nil)
+	line, err := src.ReadBytes('\n')
+	if err != nil && err != io.EOF {
+		return nil, nil, err
+	}
+
+	if httpRegex.Match(line) {
+		for {
+			_, err = headerBuffer.Write(line)
+			if err != nil {
+				return nil, nil, err
+			}
+			if (len(line) == 1 && line[0] == '\n') ||
+				(len(line) == 2 && line[0] == '\r' && line[1] == '\n') {
+				break
+			}
+
+			line, err = src.ReadBytes('\n')
+
+			if err == io.EOF {
+				_, err = headerBuffer.Write(line)
+				if err != nil {
+					return nil, nil, err
+				}
+				break
+			}
+
+			if err != nil && err != io.EOF {
+				return nil, nil, err
+			}
+		}
+	} else {
+		newsrc := bytes.NewBuffer(line)
+		_, err = newsrc.Write(src.Bytes())
+		if err != nil {
+			return nil, nil, err
+		}
+		src = newsrc
+	}
+	return headerBuffer.Bytes(), src.Bytes(), nil
+}
+
+var jsonpRegexp *regexp.Regexp = regexp.MustCompile("^([a-zA-Z$_][^ \t\r\n(]+)\\(")
+var endingParen *regexp.Regexp = regexp.MustCompile("\\)[ \t\r\n]*$")
+
+func cleanJsonp(jsonSrc []byte) ([]byte, string) {
+	match := jsonpRegexp.FindSubmatch(jsonSrc)
+	ending := endingParen.FindSubmatch(jsonSrc)
+	if match != nil && ending != nil {
+		return jsonSrc[len(match[0]) : len(jsonSrc)-len(ending[0])], string(match[1])
+	}
+	return jsonSrc, ""
+}
+
+func handleParseError(err error, jsonSrc []byte) {
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error parsing json: %v\ninput:\n%s\n", err, string(jsonSrc))
+		os.Exit(1)
+	}
+}
+
+func main() {
+	buffer := readArguments(os.Args[1:])
+	headers, jsonSrc, err := parseHeaders(buffer)
+	handleParseError(err, jsonSrc)
+
+	jsonSrc, jsonpName := cleanJsonp(jsonSrc)
+
+	if len(headers) > 0 {
+		fmt.Print(string(headers))
+	}
+
+	if jsonpName != "" {
+		fmt.Printf("jsonp method name: %s\n\n", jsonpName)
+	}
+
+	var jsonObj interface{}
+	err = json.Unmarshal(jsonSrc, &jsonObj)
+	handleParseError(err, jsonSrc)
+
+	enc := json.NewEncoder(os.Stdout)
+	enc.SetIndent("", "  ")
+	err = enc.Encode(&jsonObj)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "error encoding json: %v\n", err)
+		os.Exit(1)
+	}
+}