Reading/Web/PDF Rendering

About
As documented here, in the comment by @cscott (https://en.wikipedia.org/wiki/Wikipedia_talk:Offline_Content_Generator) and various other places, OCG was built quickly to replace code by an outside organization, PediaPress, and has had scaling and architectural issues.

The OCG service does the following:

Converts wikitext pages to latex-formatted-pdf and plain text. In the past, it has also supported zim, epub and possibly more per above, applies an attractive layout where the print.css has not provided an attractive option when integrated with the collection extension, collates articles selected by a user into books + creates a table of contents OCG is currently not well supported by the WMF and there are difficulties with Latex that have disabled table rendering in pdfs. Latex is a fairly brittle framework which is not well-suited to our incredibly flexible content-types. Furthermore, bugs in OCG or the Collection extension have greatly diminished the 3rd use of OCG (creating books).

There was significant desire from the community to provide a Latex alternative for single-article PDF rendering (captured here T135643) and we are doing this via a new service called Electron. Some of the decision making around Electron is captured here [(https://phabricator.wikimedia.org/T135643 T134205)].

Development and implementation of this service is currently underway. The WMF’s Operations team has strong reservations about running both services at once, given the heavy overlap in functionality, particularly when one of them is not well supported. They have kindly, and rightly asked us to transfer remaining features from OCG to electron and sunset it.

Future plans and timeline

 * Stage 1, in parallel, Dec - March, 2017
 * turn on electron alternative to OCG to allow tables in pdfs, per community wishlist #9 (https://phabricator.wikimedia.org/T135643 )
 * improve print CSS so that default pdf's are more attractive (https://phabricator.wikimedia.org/T135022 T135022)
 * measure user preference for new v. old pdfs (https://phabricator.wikimedia.org/T150326 T150326)


 * Stage 2, April - May, 2017
 * replicate collation of articles into a single pdf within "book creator" using Electron to replicate core missing functionality (pending)
 * identify missing OCG uses that we have missed via community consultation (T146757)


 * Stage 3, May - Jul, 2017
 * act on above results
 * communicate sunsetting (an announcement following the consultation in the earlier stage)


 * Stage 4, August 2017
 * retire OCG service
 * Probable drawbacks
 * currently there are no plans to continue to support two-column layout favored by Latex
 * currently there are no plans to continue to support plain-text conversion, epub or zim (currently not supported by OCG)


 * Metrics Implementation
 * Current usage of API's is <1% of pageviews, which we consider significant
 * measure user preference for new v. old pdfs (T150326)
 * Current usage of book creator is very limited
 * Delivery Estimate: August 30th is our deadline for turning off OCG