How to deploy pytesseract to Heroku

问题

I have a Python app which words great via Localhost on my machine.

I am trying to deploy it to Heroku. However it does not seem possible to accomplish this (I have spent approx 30 hours trying now).

The problem is Tesseract OCR. I am using the pytesseract wrapper, and my code utilises this. However, no matter what I try, it does not seem to be possible to use pytesseract when it is uploaded to Heroku.

Could anyone either suggest how to go about deploying a Hello World Tesseract OCR Python app via pytesseract to Heroku, or if Heroku is not capable of this, suggest an alternative to Heroku?

回答1:

For anyone else looking to deploy pytesseract on heroku, here are the steps:

• Add apt buildpack to heroku

  heroku buildpacks:add --index 1 https://github.com/heroku/heroku-buildpack-apt
  

• Create a file named Aptfile in the same directory as your app and these lines to it (for english)

  tesseract-ocr
  tesseract-ocr-eng
  

• Set heroku config variable TESSDATA_PREFIX to the path of tessdata folder (it was /app/.apt/usr/share/tesseract-ocr/4.00/tessdata for me) which can be found out by running heroku shell using heroku run bash and run this command in the shell

  find -iname tessdata
  

• Set the config variable using

  heroku config:set TESSDATA_PREFIX=/app/.apt/usr/share/tesseract-ocr/4.00/tessdata
  

  replace the path with the path you got from the previous command

Tesseract should be installed in the heroku app when you build it. Make sure you have pytesseract in your requirements.txt file. Now you should be able import and use pytesseract on heroku

回答2:

The Python buildpack likely doesn't have the tesseract binaries installed by default. Here’s a third-party buildpack that creates the appropriate environment. Follow the instructions there to make the binary available to your application.

来源：https://stackoverflow.com/questions/53363547/how-to-deploy-pytesseract-to-heroku