On Nov 11, 2015, at 09:28 AM, Stefan Schlott wrote:
I tried to do that ~10 years ago. I tried to implement an addition to the pipeline chain. The patch was further maintained by Joost van Baal-Ilic, who reverted the pipeline approach and made it a direct patch for Mailman. As far as I can tell, the project is resting (I haven't checked for a long time, though).
imho the pipeline chain approach is the preferable approach. I remember I still had to do some minor patches at the Mailman core because some operations weren't doable otherwise (plus the configuration settings). Unfortunately, I haven't had time to have a closer look at Mailman 3, so I can't tell if things have become easier there.
An important difference between MM2 and MM3 is that in MM2, both moderation and modification functions were intertwined in a single pipeline-of-handlers mechanism. This turned out to be to unwieldy so in MM3, we split moderation into a pre-processing chain of links-and-rules, and modification into a post-acceptance pipeline of handlers. The latter looks a lot like MM2's pipeline of handlers, except of course that it does not make moderation decisions.
Cheers, -Barry