Disable content-server's "Read this book" button?

[Geremia]

Is it possible to disable the "Read this book" button served by Calibre 3.14's content-server, so that my CPU isn't overwhelmed converting books to HTML?

[kovidgoyal]

Dont click on it if you dont want to read books. If you mean you dont want other people who access your library to use it, then setup user accounts and only give trusted people access to it.

[haertig]

The thing I don't care for in the built-in reader is that it stores the books in kind of a hidden place.

Most people are aware that their browser has a cache and stored cookies. But these days browsers also store a whole lot more "site data". Looking at my Chromium browser, I see these things stored: cookies, cache, Application cache, Cache Storage, Database storage, Local storage, File System, Channel ID, and Flash data. Many people have no idea about all this stuff that gets stored on a websites behalf (including calibre-server's internal reader's books). They don't know where it's located, how to get rid of it to free up disk space, what it's used for, etc.

Not that I use the internal reader, but if I did, I would prefer that it stored the books per the web browsers default download settings - usually either in the Download folder or "ask the user where to store it each time". Then the internal reader could save the path to the book for offline reading later. The user could accidentally (or intentionally) delete the book from wherever they downloaded it to, and thus break the internal readers linkage, but I think that would be preferable to the internal reader storing the book in this "hidden" site data area of the web browser.

The obvious answer is "don't click the button to read the book offline later". But if you don't know what that button does, and I didn't the first time I clicked it as a test, then you could end up with these hidden downloaded books following you around for the rest of your life because you don't know where they are or how to get rid of them. Maybe the internal reader has some kind of built-in cleanup to delete this stored data. That would be a nice feature.

[davidfor]

Originally Posted by Roshni Patel

Didn't got what you mean to say

I think what Kovid is really saying is that there is no way to disable the reading function with the new server. You need to rely on the users not to use the function.

Something you could do is use the mobile site. This is basically an updated version of the old site intended for low-end browsers on ereaders and the like. Add "/mobile" to the URL to use it. It doesn't have a link to read the book, just the download options.

[kovidgoyal]

There's nothing hidden about it. A bit of googling will show you how to access the browsers indexeddb storage. And just FYI web apps cannot acces sthe download folder, or indeed any folder on your computer, that would be s ecurity nightmare.

And you can delete stored books by simply accessing the books controls and choosing delete.

[haertig]

Originally Posted by kovidgoyal

And just FYI web apps cannot acces sthe download folder, or indeed any folder on your computer, that would be s ecurity nightmare.

I did not realize that. I thought they could, if you granted permission. Shows how much I know. Anyway, you're correct - it would be a security nightmare if they could access other areas of your computer without constraint. That would certainly be a disaster.

I wasn't trying to say that Calibre is trying to "hide" anything. I was just using the word "hidden" to describe an area of your computers storage that is not well known to many people. Therefore, stuff can build up there, unbeknownst to many users. Luckily, hard drives have so much capacity these days there is little need to worry about storage space. Personally, my bigger concern for these "little known storage areas" has more to do with websites tracking you and violating your privacy for their commercial purposes.

So in general, I don't like websites being able to store anything locally without my express permission. Maybe there's a setting for that in web browsers, but I haven't found the proper way to use it yet. Example: I have Chromium set to "delete cookies at the end of a browsing session", except for the specific websites I have granted permanent cookie privileges to. However, Chromium does not appear to delete other site data, aside from cookies, when I tick this "delete at end of session" checkbox. I would have expected either (1) a separate checkbox for each type of site data storage (which doesn't exist in Chromium that I can find), or (2) a single checkbox (the "cookies" one) that controls ALL of these different types of site data. But I haven't found either of these two things to be the case. So I am wary of any site data stored at all, and routinely review it manually. If I can't come up with an immediate reason for why it should be stored locally (e.g., a book from calibre-server's built-in reader), then I just delete it. Too bad, so sad for whatever web app decided it should save it on my computer.

Below is an example. Have I ever been to "weather.com"? Not to my recollection. Not that I remember even intentionally doing. It is not a website that I have granted permanent cookie privileges to, so even if I hit it accidentally, it's data should have been deleted at the end of my browsing session. Yet here is data that it has stored on my computer, apparently permanently, unbeknownst to me, until I looked just now (I have deleted it after this screenshot). Insignificant disk space is being used, but that's not the issue. The issue is that it is there in the first place. My response to behavior like this is to to tend to dislike website/apps that do this by default. I realize that some website/apps require such storage, but those should be few and far between, and subject to my explicit approval before they are allowed to store data. Maybe I just need to dig deeper into Chromiums web browser settings. This could be user error on my part.

[haertig]

p.s. - My dislike of locally stored site data is not a knock against Calibre. I realize that it needs to do exactly this if you want to be able to use it's built-in reader while offline.

I thought it would be better if Calibre could store these offline books in a more "friendly" place, like your Downloads folder, but you have corrected me and pointed out that this is not possible. I thought web apps COULD store and access data elsewhere on your computer, but only after you granted them specific permission. My error in thinking that.