Offer downloadable meta data relating to all requests on an installation

[RichardTaylor]

Offer everything available via the event history pages and /help/api as one big meta-data download.

Include request links and titles.

Enabling research, and integrations, and who knows what people might do with it...

See also

• https://www.whatdotheyknow.com/help/privacy#research
• https://github.com/mysociety/alaveteli/issues/6691

[Noted following correspondence to WDTK seeking such data]

[garethrees]

Incorporated in to and closing in favour of https://github.com/mysociety/alaveteli/issues/6691