Introduce support of OPDS catalog

[kelson42]

It support is done in the libkiwix. More infos at https://wiki.kiwix.org/wiki/OPDS

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This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[kelson42]

@BBT-SeanMacGillicuddy Would be good to have a look now if you can get all the information you need from libkiwix, at least to provide a similar feature set like currently.

[macgills]

@kelson42 is the expectation that kiwixlib provides the OPDS stream? I see no methods for it to do that with version 8.2.2

[kelson42]

@mgautierfr This is important the libkiwix provides everything about the local/remote catalog via the JNI binding, please talk together with @macgills to secure that this happens soon. If you have questions you can not solve together please let me know.

[macgills]

@kelson42 @mgautierfr
This ticket will require a lot of change and integration with the jetpack Pagination Library.

I believe the aim is to replace the current call to http://mirror.download.kiwix.org/library/library_zim.xml
with
https://library.kiwix.org/catalog/search
filling out several query parameters for searchTerm, active languages, result position and result count.
A quick question here, does this endpoint support multiple languages active at once?
There is also the possibility to filter on tag (specifically category tags?), I don't know how this is to be supported in the ui.

Changes in data returned means there will also need to be a new mechanism to load thumbnails of each book if I am interpreting the OPDS entries correctly

<entry>
    <title>Wikisource</title>
    <id>urn:uuid:010ccf61-e131-1613-e567-f1020086c7e7</id>
    <icon>/meta?name=favicon&amp;content=wikisource_fr_all_nopic_2020-01</icon>
    <updated>2020-01-18T00:00::00:Z</updated>
    <summary>La bibliothèque libre.</summary>
    <tags>wikisource;_category:wikisource;_pictures:no;_videos:no;_details:yes;_ftindex:yes</tags>
    <link type="text/html" href="/wikisource_fr_all_nopic_2020-01" />
    <author>
      <name>Wikisource</name>
    </author>
    <link rel="http://opds-spec.org/acquisition/open-access" type="application/x-zim" href="http://download.kiwix.org/zim/wikisource/wikisource_fr_all_nopic_2020-01.zim.meta4" length="9626015744" />
    <link rel="http://opds-spec.org/image/thumbnail" type="image/png" href="/meta?name=favicon&amp;content=wikisource_fr_all_nopic_2020-01" />
  </entry>

Which will involve the addition of an Image Downloading Library, most likely Picasso to handle error prone list loading/caches.
The language of the entry no longer being explicit means that the headings we create for language when showing a list of downloaded books will possibly need to be removed.

Or is this ticket that I download the data with the query parameters and then pass the raw data to kiwixlib and it returns some parsed object list similar to what the app already consumes?

Is there a schema for the OPDS catalog and is there an interface definition for kiwixlib integration?

[macgills]

does this endpoint support multiple languages active at once?

@kelson42 it does not appear to, this means our language selection will have to change to be singular and we will need a new source for where we read languages from, currently done by iterating over the library.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be now be reviewed manually. Thank you for your contributions.

[kelson42]

[kelson42]