docconv

A Go wrapper library to convert PDF, DOC, DOCX, XML, HTML, RTF, ODT, Pages documents and images (see optional dependencies below) to plain text.

Note for returning users: the Go import path for this package been moved to github.com/NICEXAI/docconv.

Installation

If you haven't setup Go before, you first need to install Go.

To fetch and build the code:

$ go get github.com/NICEXAI/docconv/...

This will also build the command line tool docd into $GOPATH/bin. Make sure that $GOPATH/bin is in your PATH environment variable.

Dependencies

tidy, wv, popplerutils, unrtf, https://github.com/JalfResi/justext

Example install of dependencies (not all systems):

$ sudo apt-get install poppler-utils wv unrtf tidy
$ go get github.com/JalfResi/justext

Optional dependencies

To add image support to the docconv library you first need to install and build gosseract.

Now you can add -tags ocr to any go command when building/fetching/testing docconv to include support for processing images:

$ go get -tags ocr github.com/NICEXAI/docconv/...

This may complain on macOS, which you can fix by installing tesseract via brew:

$ brew install tesseract

docd tool

The docd tool runs as either:

1. a service on port 8888 (by default)

   Documents can be sent as a multipart POST request and the plain text (body) and meta information are then returned as a JSON object.

2. a service exposed from within a Docker container

   This also runs as a service, but from within a Docker container. There are three build scripts:

   • ./docd/debian.sh
   • ./docd/alpine.sh
   • ./docd/appengine.sh

   The debian version uses the Debian package repository which can vary with builds. The alpine version uses a very cut down Linux distribution to produce a container ~40MB. It also locks the dependency versions for consistency, but may miss out on future updates. The appengine version is a flex based custom runtime for Google Cloud.

3. via the command line.

   Documents can be sent as an argument, e.g.

   $ docd -input document.pdf
   

Optional flags

• addr - the bind address for the HTTP server, default is ":8888"
• log-level
  • 0: errors & critical info
  • 1: inclues 0 and logs each request as well
  • 2: include 1 and logs the response payloads
• readability-length-low - sets the readability length low if the ?readability=1 parameter is set
• readability-length-high - sets the readability length high if the ?readability=1 parameter is set
• readability-stopwords-low - sets the readability stopwords low if the ?readability=1 parameter is set
• readability-stopwords-high - sets the readability stopwords high if the ?readability=1 parameter is set
• readability-max-link-density - sets the readability max link density if the ?readability=1 parameter is set
• readability-max-heading-distance - sets the readability max heading distance if the ?readability=1 parameter is set
• readability-use-classes - comma separated list of readability classes to use if the ?readability=1 parameter is set

How to start the service

$ # This will only log errors and critical info
$ docd -log-level 0

$ # This will run on port 8000 and log each request
$ docd -addr :8000 -log-level 1

Example usage (code)

Some basic code is shown below, but normally you would accept the file by HTTP or open it from the file system.

This should be enough to get you started though.

Use case 1: run locally

Note: this assumes you have the dependencies installed.

package main

import (
	"fmt"
	"log"

	"github.com/NICEXAI/docconv"
)

func main() {
	res, err := docconv.ConvertPath("your-file.pdf")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(res)
}

Use case 2: request over the network

package main

import (
	"fmt"
	"log"

	"github.com/NICEXAI/docconv/client"
)

func main() {
	// Create a new client, using the default endpoint (localhost:8888)
	c := client.New()

	res, err := client.ConvertPath(c, "your-file.pdf")
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(res)
}