Fix OnlyOffice: use internal IP for server-side URLs, create valid docx/pptx files

backend/handlers/onlyoffice.go

@@ -1,6 +1,7 @@
 package handlers
 
 import (
+	"archive/zip"
 	"fmt"
 	"io"
 	"net/http"
@@ -117,12 +118,10 @@ func (h *OnlyOfficeHandler) CreateBlank(c *fiber.Ctx) error {
 		counter++
 	}
 
-	// Create an empty file. OnlyOffice will initialize it when opened.
+	// Create a valid Office Open XML file (docx/pptx are ZIP archives)
-	f, err := os.Create(finalPath)
+	if err := createBlankOfficeFile(finalPath, ext); err != nil {
-	if err != nil {
 		return c.Status(500).JSON(fiber.Map{"error": "failed to create file"})
 	}
-	f.Close()
 
 	// Return the relative path
 	relativePath, _ := filepath.Rel(h.Config.StorageDir, finalPath)
@@ -133,6 +132,135 @@ func (h *OnlyOfficeHandler) CreateBlank(c *fiber.Ctx) error {
 	})
 }
 
+// createBlankOfficeFile creates a minimal valid .docx or .pptx file.
+// These formats are ZIP archives containing XML files following the
+// Office Open XML (OOXML) standard.
+func createBlankOfficeFile(path string, ext string) error {
+	f, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	w := zip.NewWriter(f)
+	defer w.Close()
+
+	if ext == ".pptx" {
+		return writePptxContents(w)
+	}
+	return writeDocxContents(w)
+}
+
+func writeDocxContents(w *zip.Writer) error {
+	files := map[string]string{
+		"[Content_Types].xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">
+  <Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/>
+  <Default Extension="xml" ContentType="application/xml"/>
+  <Override PartName="/word/document.xml" ContentType="application/vnd.openxmlformats-officedocument.wordprocessingml.document.main+xml"/>
+</Types>`,
+		"_rels/.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="word/document.xml"/>
+</Relationships>`,
+		"word/document.xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<w:document xmlns:w="http://schemas.openxmlformats.org/wordprocessingml/2006/main">
+  <w:body>
+    <w:p><w:r><w:t></w:t></w:r></w:p>
+  </w:body>
+</w:document>`,
+	}
+	for name, content := range files {
+		fw, err := w.Create(name)
+		if err != nil {
+			return err
+		}
+		if _, err := fw.Write([]byte(content)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writePptxContents(w *zip.Writer) error {
+	files := map[string]string{
+		"[Content_Types].xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">
+  <Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml"/>
+  <Default Extension="xml" ContentType="application/xml"/>
+  <Override PartName="/ppt/presentation.xml" ContentType="application/vnd.openxmlformats-officedocument.presentationml.presentation.main+xml"/>
+  <Override PartName="/ppt/slides/slide1.xml" ContentType="application/vnd.openxmlformats-officedocument.presentationml.slide+xml"/>
+  <Override PartName="/ppt/slideLayouts/slideLayout1.xml" ContentType="application/vnd.openxmlformats-officedocument.presentationml.slideLayout+xml"/>
+  <Override PartName="/ppt/slideMasters/slideMaster1.xml" ContentType="application/vnd.openxmlformats-officedocument.presentationml.slideMaster+xml"/>
+</Types>`,
+		"_rels/.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument" Target="ppt/presentation.xml"/>
+</Relationships>`,
+		"ppt/presentation.xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<p:presentation xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main"
+  xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"
+  xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main">
+  <p:sldMasterIdLst><p:sldMasterId id="2147483648" r:id="rId1"/></p:sldMasterIdLst>
+  <p:sldIdLst><p:sldId id="256" r:id="rId2"/></p:sldIdLst>
+  <p:sldSz cx="9144000" cy="6858000" type="screen4x3"/>
+  <p:notesSz cx="6858000" cy="9144000"/>
+</p:presentation>`,
+		"ppt/_rels/presentation.xml.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/slideMaster" Target="slideMasters/slideMaster1.xml"/>
+  <Relationship Id="rId2" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/slide" Target="slides/slide1.xml"/>
+</Relationships>`,
+		"ppt/slideMasters/slideMaster1.xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<p:sldMaster xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main"
+  xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"
+  xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main">
+  <p:cSld><p:spTree><p:nvGrpSpPr><p:cNvPr id="1" name=""/><p:cNvGrpSpPr/><p:nvPr/></p:nvGrpSpPr>
+  <p:grpSpPr><a:xfrm><a:off x="0" y="0"/><a:ext cx="0" cy="0"/><a:chOff x="0" y="0"/><a:chExt cx="0" cy="0"/></a:xfrm></p:grpSpPr>
+  </p:spTree></p:cSld>
+  <p:sldLayoutIdLst><p:sldLayoutId id="2147483649" r:id="rId1"/></p:sldLayoutIdLst>
+</p:sldMaster>`,
+		"ppt/slideMasters/_rels/slideMaster1.xml.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/slideLayout" Target="../slideLayouts/slideLayout1.xml"/>
+</Relationships>`,
+		"ppt/slideLayouts/slideLayout1.xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<p:sldLayout xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main"
+  xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"
+  xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main" type="blank">
+  <p:cSld><p:spTree><p:nvGrpSpPr><p:cNvPr id="1" name=""/><p:cNvGrpSpPr/><p:nvPr/></p:nvGrpSpPr>
+  <p:grpSpPr><a:xfrm><a:off x="0" y="0"/><a:ext cx="0" cy="0"/><a:chOff x="0" y="0"/><a:chExt cx="0" cy="0"/></a:xfrm></p:grpSpPr>
+  </p:spTree></p:cSld>
+</p:sldLayout>`,
+		"ppt/slideLayouts/_rels/slideLayout1.xml.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/slideMaster" Target="../slideMasters/slideMaster1.xml"/>
+</Relationships>`,
+		"ppt/slides/slide1.xml": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<p:sld xmlns:p="http://schemas.openxmlformats.org/presentationml/2006/main"
+  xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships"
+  xmlns:a="http://schemas.openxmlformats.org/drawingml/2006/main">
+  <p:cSld><p:spTree><p:nvGrpSpPr><p:cNvPr id="1" name=""/><p:cNvGrpSpPr/><p:nvPr/></p:nvGrpSpPr>
+  <p:grpSpPr><a:xfrm><a:off x="0" y="0"/><a:ext cx="0" cy="0"/><a:chOff x="0" y="0"/><a:chExt cx="0" cy="0"/></a:xfrm></p:grpSpPr>
+  </p:spTree></p:cSld>
+</p:sld>`,
+		"ppt/slides/_rels/slide1.xml.rels": `<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/slideLayout" Target="../slideLayouts/slideLayout1.xml"/>
+</Relationships>`,
+	}
+	for name, content := range files {
+		fw, err := w.Create(name)
+		if err != nil {
+			return err
+		}
+		if _, err := fw.Write([]byte(content)); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 // SignConfig takes the OnlyOffice configuration payload and signs it with the JWT secret
 func (h *OnlyOfficeHandler) SignConfig(c *fiber.Ctx) error {
 	if h.Config.OnlyOfficeJWT == "" {

frontend/src/components/OnlyOfficeEditor.tsx

@@ -37,17 +37,14 @@ export default function OnlyOfficeEditor({ file, type, onClose }: OnlyOfficeEdit
   useEffect(() => {
     if (!downloadToken) return;
 
-    const getApiBase = () => {
+    // The OnlyOffice Document Server fetches these URLs server-side (not from the browser).
-      if (process.env.NEXT_PUBLIC_API_URL) return process.env.NEXT_PUBLIC_API_URL;
+    // It's on the default bridge network and can reach the Unraid host IP, but NOT
-      if (typeof window !== 'undefined') return `${window.location.origin}/api`;
+    // the public domain (hairpin NAT) or Docker DNS names (different network).
-      return 'http://localhost:8080';
+    // Port 5827 is the frontend container (which proxies /api/* to the backend).
-    };
+    const INTERNAL_URL = 'http://192.168.50.81:5827/api';
-
-    const API_BASE = getApiBase();
     
-    // Use the public API_BASE which correctly routes through the Nginx proxy to the Next.js frontend
+    const fileUrl = `${INTERNAL_URL}/files/download/${encodeURIComponent(file.path)}?token=${downloadToken}`;
-    const fileUrl = `${API_BASE}/files/download/${encodeURIComponent(file.path)}?token=${downloadToken}`;
+    const callbackUrl = `${INTERNAL_URL}/public/onlyoffice/callback?path=${encodeURIComponent(file.path)}&token=${downloadToken}`;
-    const callbackUrl = `${API_BASE}/public/onlyoffice/callback?path=${encodeURIComponent(file.path)}&token=${downloadToken}`;
     
     const baseConfig: any = {
       document: {