From 1ee5436841f6674e01a060be72f72f78eb61ebcb Mon Sep 17 00:00:00 2001
From: "Michael S. Klishin" <michael@novemberain.com>
Date: Mon, 29 Aug 2011 19:36:11 +0400
Subject: [PATCH] Initial implementation of monger.collection/find-one

---
 src/monger/collection.clj       | 33 ++++++++++++++++++++++++++---
 test/monger/test/collection.clj | 37 ++++++++++++++++++++++++++++++++-
 2 files changed, 66 insertions(+), 4 deletions(-)

diff --git a/src/monger/collection.clj b/src/monger/collection.clj
index 8bf9346..2cbae45 100644
--- a/src/monger/collection.clj
+++ b/src/monger/collection.clj
@@ -16,7 +16,9 @@
 ;; API
 ;;
 
+;;
 ;; monger.collection/insert
+;;
 
 (defn ^WriteResult insert
   ([^String collection, ^DBObject document]
@@ -35,7 +37,9 @@
      (let [#^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
        (.insert #^DBCollection coll #^List (to-db-object documents) #^WriteConcern concern))))
 
+;;
 ;; monger.collection/find
+;;
 (declare fields-to-db-object)
 
 (defn ^DBCursor find
@@ -48,10 +52,27 @@
   ([^String collection, ^Map ref, ^List fields]
      (let [#^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)
            map-of-fields (fields-to-db-object fields)]
-       (.find #^DBCollection coll #^DBObject (to-db-object ref) #^DBObject (to-db-object map-of-fields))))
-  )
+       (.find #^DBCollection coll #^DBObject (to-db-object ref) #^DBObject (to-db-object map-of-fields)))))
 
 
+;;
+;; monger.collection/find-one
+;;
+
+(defn ^DBCursor find-one
+  ([^String collection, ^Map ref]
+     (let [#^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
+       (.find #^DBCollection coll #^DBObject (to-db-object ref))))
+  ([^String collection, ^Map ref, ^List fields]
+     (let [#^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)
+           map-of-fields (fields-to-db-object fields)]
+       (.find #^DBCollection coll #^DBObject (to-db-object ref) #^DBObject (to-db-object map-of-fields)))))
+
+
+;;
+;; monger.collection/find-by-id
+;;
+
 (defn ^DBObject find-by-id
   ([^String collection, ^String id]
      (let [#^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
@@ -62,10 +83,16 @@
        (.findOne #^DBCollection coll #^DBObject (to-db-object { :_id id }) #^DBObject (to-db-object map-of-fields)))))
 
 
-
+;;
 ;; monger.collection/group
+;;
 
+;; TBD
+
+
+;;
 ;; monger.collection/count
+;;
 (defn ^long count
   ([^String collection]
      (let [^DBCollection coll (.getCollection monger.core/*mongodb-database* collection)]
diff --git a/test/monger/test/collection.clj b/test/monger/test/collection.clj
index c8005bc..bb864e8 100644
--- a/test/monger/test/collection.clj
+++ b/test/monger/test/collection.clj
@@ -1,7 +1,7 @@
 (set! *warn-on-reflection* true)
 
 (ns monger.test.collection
-  (:import  [com.mongodb WriteResult WriteConcern DBCursor])
+  (:import  [com.mongodb WriteResult WriteConcern DBCursor DBObject])
   (:require [monger core collection errors util] [clojure stacktrace])
   (:use [clojure.test]))
 
@@ -107,6 +107,41 @@
     (is (instance? DBCursor cursor))))
 
 
+;;
+;; find-one
+;;
+
+(deftest find-one-full-document-when-collection-is-empty
+  (let [collection "docs"]
+    (monger.collection/remove collection)
+    (def cursor (monger.collection/find-one collection {}))
+    (is (instance? DBCursor cursor))
+    (is (empty? cursor))))
+
+(deftest find-one-full-document-when-collection-has-matches
+  (let [collection "docs"
+        doc-id     (monger.util/random-uuid)
+        doc        { :data-store "MongoDB", :language "Clojure", :_id doc-id }]
+    (monger.collection/remove collection)
+    (monger.collection/insert collection doc)
+    (def cursor (monger.collection/find-one collection { :language "Clojure" }))
+    (is (= (:_id doc) (.get (.next #^DBCursor cursor) "_id")))))
+
+
+(deftest find-one-full-document-when-collection-has-matches
+  (let [collection "docs"
+        doc-id     (monger.util/random-uuid)
+        doc        { :data-store "MongoDB", :language "Clojure", :_id doc-id }
+        fields     [:language]]
+    (monger.collection/remove collection)
+    (monger.collection/insert collection doc)
+    (def cursor (monger.collection/find-one collection { :language "Clojure" } fields))
+    (def #^DBObject loaded (.next #^DBCursor cursor))
+    (is (nil? (.get #^DBObject loaded "data-stire")))
+    (is (= doc-id (.get #^DBObject loaded "_id")))
+    (is (= "Clojure" (.get #^DBObject loaded "language")))))
+
+
 
 ;;
 ;; find-by-id