Creating a square image in Google AppEngine Python Standard Environment

README.md

Note for running this in local development server. You need to use install a older version of Pillow or PIL in order to use the image library. I tested this with Pillow 2.9 as suggested in here

create_square_image.py

def create_square_image(img):
  '''Create a square image by padding the top-bottom or left-right from the `img`.
  The implementatio relies on the GAE's images library.
  There is no example for this NICE images library... use the source, Luke.
  https://cloud.google.com/appengine/docs/standard/python/refdocs/modules/google/appengine/api/images#composite

  Params:
    img, google.appengine.api.images.Image, the original non-square image.

  Return:
    google.appengine.api.images.Image, the result square image
  '''
  side = max(img.width, img.height)
  white = 0xffffffff      # Google said it is ARGB order. So 0xffff0000 for red. (o:

  # JPEG should be better for product photos.
  new_img = images.composite((
      (img._image_data, 0, 0, 1.0, images.CENTER_CENTER),      # first image
    ),  
    width=side, height=side, color=white,
    output_encoding=images.JPEG, quality=100)
  new_img = Image(new_img)

  return new_img