Stream-first Gotenberg Client for Go / Habr

Go client for Gotenberg — document conversion service supporting Chromium, LibreOffice, and PDF manipulation engines.

go get github.com/nativebpm/gotenberg

Features

Chromium: Convert URLs, HTML, and Markdown to PDF
LibreOffice: Convert Office documents (Word, Excel, PowerPoint) to PDF
PDF Engines: Merge, split, and manipulate PDFs
Webhook support: Async conversions with callback URLs
Stream-first: Built on httpstream for efficient multipart uploads

Conversion Engines

Chromium

Convert web content to PDF:

URL → PDF
HTML file → PDF
Markdown → PDF

Supports:

Custom page properties (size, margins, orientation)
Headers & footers with page numbers
Wait strategies (delay, JavaScript expression)
Cookies & custom HTTP headers
Emulated media types (screen/print)

LibreOffice

Convert Office documents:

Word (.docx, .doc) → PDF
Excel (.xlsx, .xls) → PDF
PowerPoint (.pptx, .ppt) → PDF
OpenDocument formats → PDF

PDF Engines

PDF operations:

Merge multiple PDFs
Split pages
Convert images to PDF

Webhook Mode

Async conversions with callbacks:

Returns 204 No Content immediately
Uploads result to webhook URL in background
Separate error callback URL
Custom HTTP headers for callbacks

See Gotenberg webhook docs for details.

Example with Docker:

docker run \
  -p 3000:3000 \
  --name gotenberg \
  --add-host="host.docker.internal:host-gateway" \
  gotenberg/gotenberg:8

package main

import (
 "context"
 "io"
 "log"
 "net/http"
 "os"
 "time"

 "github.com/nativebpm/gotenberg"
)

func main() {
 client, err := gotenberg.NewClient(&http.Client{}, "http://localhost:3000")
 if err != nil {
  log.Fatal(err)
 }

 // Convert web page from URL to PDF
 resp, err := client.
  Chromium().
  ConvertURL(context.Background(), "https://gotenberg.dev/docs/getting-started/introduction").
  PaperSizeA4().
  Margins(1, 1, 1, 1).
  PrintBackground().
  Timeout(30 * time.Second).
  Send()
 if err != nil {
  log.Fatal(err)
 }
 defer resp.Body.Close()

 f, err := os.Create("converturl-chromium.pdf")
 if err != nil {
  log.Fatal(err)
 }
 defer f.Close()

 _, err = io.Copy(f, resp.Body)
 if err != nil {
  log.Fatal(err)
 }

 log.Println("PDF generated from URL: converturl-chromium.pdf")
}

package main

import (
 "context"
 "io"
 "log"
 "net/http"
 "os"
 "strings"

 "github.com/nativebpm/gotenberg"
)

func main() {
 client, err := gotenberg.NewClient(&http.Client{}, "http://localhost:3000")
 if err != nil {
  log.Fatal(err)
 }

 html := strings.NewReader("<html><body><h1>Hello World!</h1></body></html>")

 resp, err := client.Chromium().
  ConvertHTML(context.Background(), html).
  PaperSizeA6().
  Margins(0.5, 0.5, 0.5, 0.5).
  Send()
 if err != nil {
  log.Fatal(err)
 }
 defer resp.Body.Close()

 f, _ := os.Create("out.pdf")
 io.Copy(f, resp.Body)
 f.Close()
}

Full Examples

Github: https://github.com/nativebpm/gotenberg