Support links on stored values

ChangeLog.md

@@ -1,6 +1,16 @@
 ## Changes between Welle 1.0.0-alpha5 and 1.0.0-alpha6
 
-No changes yet.
+### Links support
+
+`clojurewerkz.welle.kv/store` now takes the new `:links` option that lets you store
+Riak links with the value. `clojurewerkz.welle.kv/fetch` then transparently deserializes when the value
+is fetched back:
+
+``` clojure
+(kv/store bucket-name k v :content-type Constants/CTYPE_TEXT_UTF8 :links [{:bucket "pages" :key "clojurewerkz.org" :tag "links"}])
+(let [fetched (kv/fetch-one bucket-name k)]
+  (println (:links fetched)))
+```
 
 
 ## Changes between Welle 1.0.0-alpha4 and 1.0.0-alpha5

src/clojure/clojurewerkz/welle/conversion.clj

@@ -2,9 +2,10 @@
   (:require [clojure.data.json :as json]
             [clojure.set       :as cs]
             [clojure.java.io   :as io])
+  (:use     [clojure.walk :only [stringify-keys]])
   (:import [com.basho.riak.client.cap Quora Quorum VClock BasicVClock]
            [com.basho.riak.client.raw StoreMeta FetchMeta DeleteMeta]
-           com.basho.riak.client.IRiakObject
+           [com.basho.riak.client IRiakObject RiakLink]
            [com.basho.riak.client.builders RiakObjectBuilder BucketPropertiesBuilder]
            [com.basho.riak.client.bucket BucketProperties TunableCAPProps]
            com.basho.riak.client.http.util.Constants
@@ -123,15 +124,27 @@
 
 ;; Clojure <=> IRiakObject
 
+(defn ^com.basho.riak.client.RiakLink
+  to-riak-link
+  "Converts a Clojure map to a RiakLink instance"
+  [m]
+  (let [m (stringify-keys m)]
+    (RiakLink. (get m "bucket") (get m "key") (get m "tag"))))
+
+(defn from-riak-link
+  "Converts a RiakLink instance to a Clojure map"
+  [^RiakLink rl]
+  {:bucket (.getBucket rl) :key (.getKey rl) :tag (.getTag rl)})
+
 (declare deserialize)
 (defn to-riak-object
   "Builds a Riak object from a Clojure map of well-known attributes:
    :value, :content-type, :metadata, :indexes, :vclock, :vtag, :last-modified"
   (^com.basho.riak.client.IRiakObject
-   [{:keys [^String bucket ^String key value content-type metadata indexes vclock vtag last-modified]
+   [{:keys [^String bucket ^String key value content-type metadata indexes
+            vclock vtag last-modified links]
      :or {content-type Constants/CTYPE_OCTET_STREAM
-          metadata     {}
-          indexes      []}
+          metadata     {}}
      :as options}]
    (let [^RiakObjectBuilder bldr (doto (RiakObjectBuilder/newBuilder (name bucket) (name key))
                                    (.withValue        value)
@@ -140,10 +153,13 @@
      (when vclock        (.withVClock bldr ^VClock (to-vclock vclock)))
      (when vtag          (.withVtag bldr vtag))
      (when last-modified (.withLastModified bldr last-modified))
-     ;; TODO: this code breaks when indexed values are not collections
-     (doseq [[idx-key idx-vals] indexes
-             idx-val (if (coll? idx-vals) idx-vals [idx-vals])]
-       (.addIndex bldr ^String (name idx-key) idx-val))
+     (when-let [indexes (seq indexes)]
+       ;; TODO: this code breaks when indexed values are not collections
+       (doseq [[idx-key idx-vals] indexes
+               idx-val (if (coll? idx-vals) idx-vals [idx-vals])]
+         (.addIndex bldr ^String (name idx-key) idx-val)))
+     (when-let [xs (seq links)]
+       (.withLinks bldr (map to-riak-link xs)))
      (.build bldr))))
 
 (defn indexes-from
@@ -158,17 +174,22 @@
                     (merge-with cs/union acc-m {idx-name idx-fields})))]
     (reduce step {} indexes)))
 
+(defn links-from
+  "Returns links on the given IRiakObject as a lazy sequence of Clojure maps"
+  [^IRiakObject ro]
+  (map from-riak-link (.getLinks ro)))
+
 (defn from-riak-object
   "Converts IRiakObjects to a Clojure map"
   [^IRiakObject ro]
-
   {:vclock        (.getVClock ro)
    :content-type  (.getContentType ro)
    :vtag          (.getVtag ro)
    :last-modified (.getLastModified ro)
    :metadata      (into {} (.getMeta ro))
    :value         (.getValue ro)
-   :indexes       (indexes-from ro)})
+   :indexes       (indexes-from ro)
+   :links         (links-from ro)})
 
 
 ;; Index queries

src/clojure/clojurewerkz/welle/kv.clj

@@ -24,7 +24,7 @@
 (defn store
   "Stores an object in Riak"
   [^String bucket-name ^String key value &{ :keys [w dw pw
-                                                   indexes vclock ^String vtag ^Long last-modified
+                                                   indexes links vclock ^String vtag ^Long last-modified
                                                    ^Boolean return-body ^Boolean if-none-match ^Boolean if-not-modified
                                                    content-type metadata]
                                            :or {content-type Constants/CTYPE_OCTET_STREAM
@@ -37,6 +37,7 @@
                                          :content-type  content-type
                                          :metadata      (stringify-keys metadata)
                                          :indexes       indexes
+                                         :links         links
                                          :vclock        vclock
                                          :vtag          vtag
                                          :last-modified last-modified})

test/clojurewerkz/welle/test/conversion_test.clj

@@ -4,7 +4,7 @@
            com.basho.riak.client.bucket.TunableCAPProps
            com.basho.riak.client.util.CharsetUtils
            com.basho.riak.client.http.util.Constants
-           com.basho.riak.client.IRiakObject
+           [com.basho.riak.client IRiakObject RiakLink]
            [java.util Date UUID]))
 
 (set! *warn-on-reflection* true)
@@ -110,12 +110,16 @@
           metadata     {"metakey" "metavalue"}
           indexes      {"handle"  #{"johnnyriak"}}
           vclock       (vclock-for "vclock for a riak object")
-          ro           (to-riak-object {:bucket bucket :key key :value value :content-type content-type :metadata metadata :indexes indexes :vclock vclock})]
+          links        [{:bucket "pages" :key "http://clojurewerkz.org" :tag "links"}
+                        {:bucket "pages" :key "http://clojureriak.info" :tag "links"}]
+          ro           (to-riak-object {:bucket bucket :key key :value value :content-type content-type :metadata metadata :indexes indexes :vclock vclock :links links})]
       (is (= bucket       (.getBucket ro)))
       (is (= key          (.getKey ro)))
       (is (= "A value"    (.getValueAsString ro)))
       (is (= content-type (.getContentType ro)))
-      (is (= vclock       (.getVClock ro))))))
+      (is (= vclock       (.getVClock ro)))
+      (is (.hasLinks ro))
+      (is (= 2 (.numLinks ro))))))
 
 (deftest test-to-bucket-properties
   (testing "case 1"
@@ -234,3 +238,18 @@
           query       (to-index-query value bucket-name index-name)]
       (is (= "email_bin" (.getIndex query)))
       (is (= bucket-name (.getBucket query))))))
+
+
+(deftest test-to-riak-link
+  (testing "positive scenario"
+    (let [m  {:bucket "pages" :key "http://clojureriak.info" :tag "links"}
+          rl (to-riak-link m)]
+      (is (= "pages" (.getBucket rl)))
+      (is (= "http://clojureriak.info" (.getKey rl)))
+      (is (= "links" (.getTag rl))))))
+
+(deftest test-from-riak-link
+  (testing "positive scenario"
+    (let [m  {:bucket "pages" :key "http://clojureriak.info" :tag "links"}
+          rl (RiakLink. "pages" "http://clojureriak.info" "links")]
+      (is (= m (from-riak-link rl))))))

test/clojurewerkz/welle/test/kv_test.clj

@@ -98,7 +98,7 @@
         v           (merge {:city "New York City" :state "NY" :year 2011 :participants #{"johndoe" "timsmith" "michaelblack"}
                             :venue {:name "Sheraton New York Hotel & Towers" :address "811 Seventh Avenue" :street "Seventh Avenue"}}
                            ;; on Clojure 1.4+, we can add date to this map, too. Clojure 1.4's extensible reader has extensions for
-                           ;; Date/instant serialization but 1.3 will fail. MK.                           
+                           ;; Date/instant serialization but 1.3 will fail. MK.
                            (when clojure14?
                              {:date (java.util.Date.)}))
         ct          "application/clojure"
@@ -148,6 +148,25 @@
     (drain bucket-name)))
 
 
+;;
+;; Links
+;;
+
+(deftest test-basic-store-with-links
+  (let [bucket-name "clojurewerkz.welle.kv/store-with-given-links"
+        bucket      (wb/update bucket-name)
+        k           (str (UUID/randomUUID))
+        v           "value"
+        links       [{:bucket "pages" :key "clojurewerkz.org" :tag "links"}]
+        stored      (kv/store bucket-name k v :content-type Constants/CTYPE_TEXT_UTF8 :links links)
+        [fetched]   (kv/fetch bucket-name k)]
+    (is (= Constants/CTYPE_TEXT_UTF8 (:content-type fetched)))
+    (is (= links (:links fetched)))
+    (is (= v (:value fetched)))
+    (is-riak-object fetched)
+    (drain bucket-name)))
+
+
 
 ;;
 ;; kv/fetch, kv/fetch-one