Support Older Kindles

[fakerybakery]

Hi,
Thanks for making this great resource! I noticed that Gutendex's API only gave the KF8 file format for Kindles, which is only compatible with newer Kindles. However, on Gutenberg's official website, they have two files, "Kindle" and "older Kindles."
I'm not sure if Gutenberg's downloadable API supports this, but I was wondering if it might be possible to include these files as well.
Thank you!
EDIT: Right now, I'm just replacing ".kf8" with ".kindle" because of Gutenberg's file naming convention, but I'm not sure if there's a better way to do this.

[garethbjohnson]

Hi, good idea! In this case, there are two formats (".kindle" and ".kf8") with the same media type ("application/x-mobipocket-ebook"), so since Gutendex uses a JSON object with unique keys for the format, it only shows one.

I could add another property to the API object with the key "all_formats" and a value that is an array of two-item sub-arrays, where the first item of the sub-array is the media type and the second is the URL for that format. For example:

{
  ...
  "formats": {
    ...
    "application/x-mobipocket-ebook": "https://www.gutenberg.org/ebooks/84.kf8.images",
    ...
  },
  "all_formats": [
    ...
    ["application/x-mobipocket-ebook", "https://www.gutenberg.org/ebooks/84.kindle.images"],
    ["application/x-mobipocket-ebook", "https://www.gutenberg.org/ebooks/84.kf8.images"],
    ...
  ],
  ...
}

Would that solve the issue?

[fakerybakery]

Hmm, yeah that's an option. Have you considered giving the older kindle option a custom name, ie "application/mobipocket-x-ebook-old"?

[fakerybakery]

Hi, just saw the file size thread. Your previous solution would be great, but it might break applications depending on an older version of the API. Is it possible to support an extra flag ("?all_versions=true")?

[garethbjohnson]

Hi, thank you for the feedback. I would like to keep the existing "formats" and simply add "all_formats" after it, so I foresee no issue. I do not expect it to be common enough for any apps to rely on the size of responses, or to reject responses with unexpected properties. Even if a developer needs to update their app to support the new property, they could use the previous commit on their servers. Does that make sense?

[fakerybakery]

Yeah, that makes sense. Thanks for the explanation!