GeoTaskList tutorial #2 Appengine Persistence

persistence.clj

;Follow the blog posts for this code here: http://www.digitalbricklayers.com/2012/03/geotasklist-part-2.html
(ns GeoTaskList.persistence
  (:require [appengine-magic.services.datastore :as ds]))


(ds/defentity Location [^:key locationId, ^:clj location])

;Save a location. -1 is used to signify no id passed in and nil
;should be substitued
(defn save-location [location-map] 
  (let [input-id (Integer/parseInt (:locationId location-map))
        id (if (= input-id -1) nil input-id)]
    (ds/save! (Location. id location-map))))

;Loads all locations. Retrieves the location field map for all locations
; and then adds in the locationId key value pair for each location.
(defn get-all-locations [] 
  (map 
    (fn [k] 
      (assoc (:location k) :locationId (ds/key-id k)));This line sets the id onto the map at load time 
    (ds/query :kind Location)))
 
;Deletes a location by locationId
(defn delete-location [locationId] 
  (ds/delete! 
    (ds/retrieve Location locationId)))