package main
import (
"encoding/json"
"fmt"
"html/template"
"io"
"log"
"net/http"
"net/url"
"strings"
"time"
gliffy2drawio "gliffy2drawio"
)
const (
maxUploadSize = 10 << 20 // 10MB
)
var diagramStore = struct {
data map[string]string
}{
data: make(map[string]string),
}
var uploadTpl = template.Must(template.New("upload").Parse(`
Gliffy β draw.io Converter
Gliffy β draw.io Converter
Upload a .gliffy (zip) or .gon JSON file. Convert to .drawio, or open directly in diagrams.net.
`))
type apiRequest struct {
Data string `json:"data"` // raw Gliffy JSON
}
type apiResponse struct {
XML string `json:"xml"`
Warn string `json:"warning,omitempty"`
}
func main() {
mux := http.NewServeMux()
mux.HandleFunc("/", uploadHandler)
mux.HandleFunc("/convert", uploadConvertHandler)
mux.HandleFunc("/open", uploadOpenHandler)
mux.HandleFunc("/api/convert", apiConvertHandler)
mux.HandleFunc("/openapi.json", openAPISpecHandler)
mux.HandleFunc("/swagger", swaggerUIHandler)
mux.HandleFunc("/diagram", diagramHandler)
addr := ":8080"
log.Printf("Server listening on %s", addr)
log.Fatal(http.ListenAndServe(addr, mux))
}
func uploadHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodGet {
http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
return
}
if err := uploadTpl.Execute(w, nil); err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
}
}
func uploadConvertHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodPost {
http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
return
}
log.Printf("[upload] %s %s from %s", r.Method, r.URL.Path, r.RemoteAddr)
r.Body = http.MaxBytesReader(w, r.Body, maxUploadSize)
if err := r.ParseMultipartForm(maxUploadSize); err != nil {
http.Error(w, "failed to parse form: "+err.Error(), http.StatusBadRequest)
return
}
file, header, err := r.FormFile("file")
if err != nil {
http.Error(w, "missing file: "+err.Error(), http.StatusBadRequest)
return
}
defer file.Close()
data, err := io.ReadAll(file)
if err != nil {
http.Error(w, "failed to read file: "+err.Error(), http.StatusInternalServerError)
return
}
xml, warn, err := convert(string(data))
if err != nil {
log.Printf("[upload] conversion failed: %v", err)
http.Error(w, "conversion failed: "+err.Error(), http.StatusBadRequest)
return
}
w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s.drawio"`, safeName(header.Filename)))
w.Header().Set("Content-Type", "application/xml")
if warn != "" {
w.Header().Set("X-Conversion-Warning", warn)
}
log.Printf("[upload] conversion succeeded, warn: %q, bytes out: %d", warn, len(xml))
_, _ = w.Write([]byte(xml))
}
func uploadOpenHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodPost {
http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
return
}
log.Printf("[open] %s %s from %s", r.Method, r.URL.Path, r.RemoteAddr)
r.Body = http.MaxBytesReader(w, r.Body, maxUploadSize)
if err := r.ParseMultipartForm(maxUploadSize); err != nil {
http.Error(w, "failed to parse form: "+err.Error(), http.StatusBadRequest)
return
}
file, _, err := r.FormFile("file")
if err != nil {
http.Error(w, "missing file: "+err.Error(), http.StatusBadRequest)
return
}
defer file.Close()
data, err := io.ReadAll(file)
if err != nil {
http.Error(w, "failed to read file: "+err.Error(), http.StatusInternalServerError)
return
}
xml, warn, err := convert(string(data))
if err != nil {
log.Printf("[open] conversion failed: %v", err)
http.Error(w, "conversion failed: "+err.Error(), http.StatusBadRequest)
return
}
if warn != "" {
log.Printf("[open] conversion warning: %s", warn)
}
id := storeDiagram(xml)
targetURL := buildDiagramsNetURL(r, id)
log.Printf("[open] redirecting to %s", targetURL)
http.Redirect(w, r, targetURL, http.StatusFound)
}
func apiConvertHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodPost {
http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
return
}
log.Printf("[api] %s %s from %s", r.Method, r.URL.Path, r.RemoteAddr)
defer r.Body.Close()
var req apiRequest
if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
http.Error(w, "invalid JSON: "+err.Error(), http.StatusBadRequest)
return
}
xml, warn, err := convert(req.Data)
if err != nil {
log.Printf("[api] conversion failed: %v", err)
http.Error(w, "conversion failed: "+err.Error(), http.StatusBadRequest)
return
}
resp := apiResponse{XML: xml, Warn: warn}
w.Header().Set("Content-Type", "application/json")
log.Printf("[api] conversion succeeded, warn: %q, bytes out: %d", warn, len(xml))
_ = json.NewEncoder(w).Encode(resp)
}
func convert(gliffyJSON string) (string, string, error) {
log.Printf("[convert] starting, input bytes: %d", len(gliffyJSON))
converter, err := gliffy2drawio.NewGliffyDiagramConverter(gliffyJSON)
if err != nil {
log.Printf("[convert] failed to initialize converter: %v", err)
return "", "", err
}
xml, err := converter.GraphXML()
if err != nil {
log.Printf("[convert] failed to generate XML: %v", err)
return "", "", err
}
warn := ""
log.Printf("[convert] done, output bytes: %d", len(xml))
return xml, warn, nil
}
func safeName(name string) string {
if name == "" {
return "diagram"
}
dot := strings.LastIndex(name, ".")
if dot > 0 {
name = name[:dot]
}
name = strings.ReplaceAll(name, "\"", "")
return name
}
func openAPISpecHandler(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
_, _ = w.Write([]byte(openAPISpec))
}
func diagramHandler(w http.ResponseWriter, r *http.Request) {
if r.Method == http.MethodOptions {
addCORS(w)
w.WriteHeader(http.StatusNoContent)
return
}
id := r.URL.Query().Get("id")
if id == "" {
http.Error(w, "missing id", http.StatusBadRequest)
return
}
xml, ok := diagramStore.data[id]
if !ok {
http.Error(w, "not found", http.StatusNotFound)
return
}
addCORS(w)
w.Header().Set("Content-Type", "application/xml")
_, _ = w.Write([]byte(xml))
}
func storeDiagram(xml string) string {
now := time.Now().UnixNano()
id := fmt.Sprintf("diag-%d", now)
diagramStore.data[id] = xml
return id
}
func buildDiagramsNetURL(r *http.Request, id string) string {
scheme := "http"
if r.Header.Get("X-Forwarded-Proto") == "https" || r.TLS != nil {
scheme = "https"
}
base := fmt.Sprintf("%s://%s/diagram?id=%s", scheme, r.Host, url.QueryEscape(id))
// Request AWS library for custom shapes (e.g., aws4) to render correctly.
return "https://app.diagrams.net/?splash=0&ui=min&libs=aws4&url=" + url.QueryEscape(base)
}
func addCORS(w http.ResponseWriter) {
w.Header().Set("Access-Control-Allow-Origin", "*")
w.Header().Set("Access-Control-Allow-Methods", "GET, OPTIONS")
w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
}
func swaggerUIHandler(w http.ResponseWriter, r *http.Request) {
if r.Method != http.MethodGet {
http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
return
}
swaggerHTML := `
Gliffy β draw.io API
`
w.Header().Set("Content-Type", "text/html; charset=utf-8")
_, _ = w.Write([]byte(swaggerHTML))
}
var openAPISpec = `
{
"openapi": "3.0.0",
"info": {
"title": "Gliffy to draw.io Converter",
"version": "1.0.0"
},
"paths": {
"/api/convert": {
"post": {
"summary": "Convert Gliffy JSON to draw.io XML",
"requestBody": {
"required": true,
"content": {
"application/json": {
"schema": {
"type": "object",
"properties": {
"data": {
"type": "string",
"description": "Raw Gliffy JSON content"
}
},
"required": ["data"]
}
}
}
},
"responses": {
"200": {
"description": "Conversion succeeded",
"content": {
"application/json": {
"schema": {
"type": "object",
"properties": {
"xml": { "type": "string" },
"warning": { "type": "string" }
}
}
}
}
},
"400": {
"description": "Conversion failed"
}
}
}
}
}
}
`