Converting webdev to Datomic


#1

Am going to go ahead and try moving the video’s webdev app to Datomic. It seems that it should just be a rewriting of the model class and pointing to a new db if I’m reading this correctly? Can make the repo available if I start to get somewhere.

(Interestingly - when including datomic in the project dependencies, the server will still start, but it won’t print out the first two lines of jetty identifying information. I troubleshooted for some time thinking if was hanging and didn’t find a way to have leiningen give a verbose dump. But it really seems to be that single dependency. curl dumps the same header.)


#2

Hey, sounds cool! Do please post it somewhere (and link to it from here).

About the jetty status lines, I wonder if datomic redefines out or something. That’s a weird thing to do.


#3

Will do Eric - I’ll post the repo when done.

It has been easier than I thought actually. I have the reading and writing to Datomic working and hope to have some time to get to the others today. The deletion I’m doing a bit differently since Datomic doesn’t “like” excising data. I’ve just created an extra boolean flag called Active and the the Datalog query only reads those items which haven’t been inactivated (/deleted).
Kevin


#4

Good idea.

Have you had trouble excising? I’m sure that at some point, you will actually want to forget some data for legal reasons. I heard that it was implemented, but have not tried it myself.


#5

Yes - excision is supported for such causes (legal, etc.) but from my limited take of reading their docs they don’t mean it to be used for average data deletion.

http://docs.datomic.com/excision.html

But no - haven’t personally tried it myself.


#6

I’m actually going through a similar exercise with step zero being doing some learning here: http://www.datomic.com/training.html

I’ve already went through this: http://www.learndatalogtoday.org

Work will be committed here: https://github.com/chadhs/listopia


#7

Awesome. Can’t wait to see it.


#8

+1 looking forward to it


#9

Hoping within the next 2-3 weeks, unless I run into snags.