Hi list, The Google App Engine (GAE) Datastore is basically a collection of Entity objects; an Entity is a PropertyContainer (map of name-value pairs) extended to support a distinguished Key field. Clojure fits with this conceptual structure very nicely; the migae representation of the Entity class uses deftype PersistentEntityMap, which behaves just like an ordinary Clojure map. (It also behaves like a map entry). Only a few datastore-specific operations are needed, so for the most part you can completely ignore the underlying structure of Java classes and work exclusively within a Clojure data idiom.
That's the theory, anyway. The migae datastore lib <https://github.com/migae/datastore> is still very much a work in progress, but I've gotten far enough along to think that it will actually work, so I think it's time to share it and solicit feedback and advice. In particular, I'm experimenting with various API design alternatives, some of which are a little nutty - a major virtue of Clojure that I don't recall every seeing mentioned is that it supports incremental design of new abstractions on old libraries, thanks to the Java interop and other facilities. You don't have to cover the entire API at once; you can work on small bits. In any case, if you enjoy software API design you'll find lots of interesting challenges in trying to put a Clojure face on the low level Java Datastore API. (It's possible to use the lib in an actual GAE application - see migae <https://github.com/migae/migae> for a description of a technique for using Clojure to develop GAE applications - but at the moment it's better thought of as an R&D project for exploration.) Implementation wise I could certainly use some help. I'm afraid I don't work with Clojure frequently enough to have developed a style, and I'm sure my code exhibits lots of bad and naive habits. You don't have to have a GAE account to explore it. It uses Google's gradle-based build system, which is rather nice; like leiningen, it will download and install everything you need (in ~/.gradle). To explore the lib take a look at (and run) the unit tests - I've tried to design them not only as tests but as documentation. You can also use the lib in the repl, thanks to the local testing environment that comes with the GAE SDK. Cheers, Gregg -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
