onecatper.day/main.py

# uses https://thecatapi.com/ to get an image of a cat

# todo on python side
# learn about rss and how to use this script to update a feed         

import requests
import datetime

# this will change between calls due to microseconds
# better for it just to be a global
DATETIME_STR = str(datetime.datetime.today()).replace(' ', "-")
# we don't need those pesky microseconds any way
DATETIME_STR = DATETIME_STR[:-10]

def get_image_url():

    # you can ask for a cat without a key, but the free tier has some nice benefits
    # note below that I ask for 10 cats, which is the maximum with no api key. Having an
    # api key gets you access to more cats however, which is purrfect for our needs
    api_key = ""
    with open(".secrets", "r") as f:
        api_key = f.readline()

    # I ask for 10 cats because I don't want an animated gif to use as the cat image of the day
    # I'm specifically looking for a jpg, and may look for specific image dimeensions as well in the future
    data = requests.get("https://api.thecatapi.com/v1/images/search?limit=10", headers={"x-api-key" : f"{api_key}"})
    data = data.json()

    # create a list of dictionaries
    # each dictonary has the following keys
    # url - the url to the iamge
    # height - the height of the image in px
    # width - the width of the image in px
    image_data = {}
    image_data_list = []

    for url in data:
        image_data["url"] = url["url"]
        image_data["height"] = url["height"]
        image_data["width"] = url["width"]
        image_data_list.append(image_data)
        image_data = {}

    # we're looking for images of a specific height to help with a new image being on the
    # index page every day. I've stored the width property if it is ever needed as well.
    # As of now, it is not.
    urls = []   
    for properties in image_data_list:
        if properties["height"] >= 500 and properties["height"] <= 700:
             urls.append(properties["url"])

    image_url = ""

    # not a big deal if both happen to be a jpg, but elminates the possibility of saving a gif to disk
    for url in urls:
        if ".jpg" in url:
            image_url = url
    return image_url

def update_html_img_tag(index):
    old_img_tag = ""
    tag_list = []
    with open(index, "r") as f:
        index_file = f.read()
    element_list = index_file.split('\n')
    
    items = ""
    for el in element_list:
        if "<img" in el:
            items += el

    split_img_element = items.split(" ")
    time = datetime.datetime.today()
    time = str(time).strip()
    for i in range(0, len(split_img_element)):
        if "src=" in split_img_element[i]:
            split_img_element[i] = f"src=img/cat{DATETIME_STR}.jpg"
    in_progress_img_tag = " ".join(split_img_element)

    # cleaning up some things that don't need to be in the tag before writing it to index.html
    img_element_as_list = in_progress_img_tag.split(" ")
    new_img_tag = " ".join(img_element_as_list)

    
    index_file = index_file.replace(items, new_img_tag)

    with open(index, "w") as f:
        f.write(index_file)

def main():
    update_html_img_tag("index.html")   

    image_url = get_image_url()

    # with our requirements for image picking in the above function, it is possible we end up
    # with no url to get an image from. If that is the case, image_url will be empty.
    # It can only be empty or have a url, so we should call it again if it is empty.
    while image_url == "":
        image_url = get_image_url()

    # get the actual image and write to disk
    # img/ should be a folder relative to main.py
    image = requests.get(image_url)
    path = "img/"

    # a consistent name and placement of the image makes it easy for the index page to update
    # when this script is run.
    
    with open(f"{path}cat{DATETIME_STR}.jpg", "wb") as f:
        f.write(image.content)

main()