cover.py

from PIL import Image
import requests # request img from web
import shutil # save img locally
import re
import base64
import os
import concurrent.futures
from io import BytesIO  
from requests.adapters import HTTPAdapter
from urllib3.util.retry import Retry
import logging
 
logger = logging.getLogger(__name__)

def add_margin(pil_img, right, left):
    width, height = pil_img.size
    new_width = width + right + left
    result = Image.new("RGBA", (new_width, height),(255,0,0,0))
    result.paste(pil_img, (left, 0))
    return result

def to_base64(image):
    buffered = BytesIO()
    image.save(buffered, format="PNG")
    img_str = base64.b64encode(buffered.getvalue())
    return img_str

def downlaod(url,file_name):
    res = requests.get(url, stream = True)
    if res.status_code == 200:
        with open(file_name,'wb') as f:
            shutil.copyfileobj(res.raw, f)
        logger.info(f"Image successfully Downloaded - {file_name}")
    else:
        logger.error("Failed to Download image")

def upload(img_str):
    image_host_key = os.getenv('IMAGE_HOST_KEY')
    image_host_url = "https://freeimage.host/api/1/upload"

    data = {
        "key":image_host_key,
        "source":img_str,
        "action":"upload",
        "format":"json"
    }
    with requests.Session() as s:
        retry = Retry(connect=3, backoff_factor=0.1)
        adapter = HTTPAdapter(max_retries=retry)
        s.mount('http://', adapter)
        s.mount('https://', adapter)
        r = s.post(image_host_url,data=data)
        return r.json()["image"]["url"]

def get_url(url):
    #ID and file_name
    id = re.search(r"(https?:\/\/books.google.com\/books\/(publisher\/)?content\?id=)(.{12})(.*)",url).group(3)
    file_name = f"covers/{id}.png"
    #Create covers directory if doesn't exist
    if not os.path.isdir('covers'):
        os.mkdir('covers')
    #Downlaod thumbnail
    logger.info("Starting to Download image")
    downlaod(url,file_name)
    thumbnail= Image.open(file_name)
    #Dimensions
    height = thumbnail.size[1]
    width = thumbnail.size[0]
    icon_margin = int((height-width)/2)
    cover_width = int((height*7)/5)
    cover_margin = int((cover_width-width)/1.09)
    with concurrent.futures.ProcessPoolExecutor() as executor:
        #Add margins
        icon_add_margin = executor.submit(add_margin,thumbnail,icon_margin,icon_margin)
        cover_add_margin = executor.submit(add_margin,thumbnail,cover_margin,cover_margin)
        logger.info("Starting to add margins to images")
        icon_image = icon_add_margin.result()
        cover_image = cover_add_margin.result()
        logger.info("Margin adding completed")
        #To base64
        icon_to_base64 = executor.submit(to_base64,icon_image)
        cover_to_base64 = executor.submit(to_base64,cover_image)
        logger.info("Encoding images to base64 string")
        icon_str = icon_to_base64.result()
        cover_str = cover_to_base64.result() 
        logger.info("finished encoding")
        #Upload
        icon_upload = executor.submit(upload,icon_str)
        cover_upload = executor.submit(upload,cover_str)
        logger.info("Starting to upload images")
        icon_url = icon_upload.result()
        cover_url = cover_upload.result()
        logger.info("Upload completed")
        
        urls = {
            "icon":icon_url,
            "cover":cover_url
        }
        return urls