Add specialized identity convertion of DBObjects, makes it very easy to insert an object and immediately fetch its _id from it

src/monger/convertion.clj

@@ -22,7 +22,7 @@
 ;; THE SOFTWARE.
 
 (ns monger.convertion
-  (:import (com.mongodb DBObject BasicDBObject BasicDBList)
+  (:import (com.mongodb DBObject BasicDBObject BasicDBList DBCursor)
            (clojure.lang IPersistentMap Keyword)
            (java.util List Map)))
 
@@ -49,7 +49,10 @@
       o))
 
   List
-  (to-db-object [#^List input] (map to-db-object input)))
+  (to-db-object [#^List input] (map to-db-object input))
+
+  DBObject
+  (to-db-object [#^DBObject input] input))
 
 
 
@@ -83,7 +86,16 @@
     ;; subclass GridFSFile unhelpfully throws
     ;; UnsupportedOperationException
     (associate-pairs (for [key-set (.keySet input)] [key-set (.get input key-set)])
-                     keywordize)))
+                     keywordize))
+
+  ;; this idea needs to be tested out first, we will see how well
+  ;; it works. MK.
+  ;; DBCursor
+  ;; (from-db-object [^DBCursor input]
+  ;;   (if (empty? input)
+  ;;     []
+  ;;     (lazy-seq (seq input))))
+  )
 
 
 (defn- associate-pairs [pairs keywordize]

test/monger/test/collection.clj

@@ -2,7 +2,7 @@
 
 (ns monger.test.collection
   (:import  [com.mongodb WriteResult WriteConcern DBCursor DBObject] [java.util Date])
-  (:require [monger core collection result util] [clojure stacktrace])
+  (:require [monger core collection result util convertion] [clojure stacktrace])
   (:use [clojure.test]))
 
 (monger.util/with-ns 'monger.core
@@ -22,7 +22,6 @@
     (is (monger.result/ok? (monger.collection/insert "people" doc)))
     (is (= 1 (monger.collection/count collection)))))
 
-
 (deftest insert-a-basic-document-without-id-and-with-explicit-write-concern
   (let [collection "people"
         doc        { :name "Joe", :age 30 }]
@@ -30,6 +29,14 @@
     (is (monger.result/ok? (monger.collection/insert "people" doc WriteConcern/SAFE)))
     (is (= 1 (monger.collection/count collection)))))
 
+(deftest insert-a-basic-db-boject-without-id-and-with-default-write-concern
+  (let [collection "people"
+        doc        (monger.convertion/to-db-object { :name "Joe", :age 30 })]
+    (monger.collection/remove collection)
+    (is (nil? (.get doc "_id")))
+    (monger.collection/insert "people" doc)
+    (is (not (nil? (.get doc "_id"))))))
+
 
 
 ;;

test/monger/test/convertion.clj

@@ -5,7 +5,7 @@
 
 
 ;;
-;; DBObject to Clojure
+;; Clojure to DBObject
 ;;
 
 (deftest convert-nil-to-dbobject
@@ -47,9 +47,18 @@
     (is (= '(1 "a" "b") (.get inner "list")))
     (is (= { "key" "value" } (.get inner "map")))))
 
+;; for cases when you want to pass in a DBObject, for example,
+;; to obtain _id that was generated. MK.
+(deftest convert-dbobject-to-dbobject
+  (let [input  (BasicDBObject.)
+        output (monger.convertion/to-db-object input)]
+    (is (= input output))))
+
+
+
 
 ;;
-;; Clojure to DBObject
+;; DBObject to Clojure
 ;;
 
 (deftest convert-nil-from-db-object