Initial Commit of Chameleon

Commit the initial set of code for the Chameleon offering to ONAP

Change-Id: Ia58bd49eafc0a3702c17c9cab34d666ed1627ba5
Issue-ID: AAI-797
Signed-off-by: Adrian Batos-Parac <adrian.batos-parac@amdocs.com>

7 files changed, 222 insertions, 0 deletions

diff --git a/src/chameleon/aai_processor.clj b/src/chameleon/aai_processor.clj
new file mode 100644
index 0000000..c709ed1
--- /dev/null
+++ b/src/chameleon/aai_processor.clj
@@ -0,0 +1,26 @@
+(ns chameleon.aai-processor
+  (:require [chameleon.txform :refer :all]
+            [chameleon.route :refer :all]
+            [cheshire.core :refer :all]))
+
+(defn from-gallifrey
+  "Transforms Gallifrey response payloads into a format consumable by AAI-centric clients"
+  [body]
+  (->> body
+       (map (fn [[k v]] [(clojure.string/split k #"\.") v]))
+       ((fn [x] (reduce #(assoc-in %1 (first %2) (second %2) ) {} x)))))
+
+(defn from-spike
+  "Transforms Spike-based event payloads to a format accepted by Gallifrey for vertices and relationships"
+  [gallifrey-host payload]
+  (let [txpayload (map-keywords (parse-string payload))
+        operation (:operation txpayload)
+        entity-type (if (contains? txpayload :vertex)
+                      :vertex
+                      :relationship)
+        entity (map-keywords (entity-type txpayload))
+        key (:key entity)
+        properties (assoc (:properties entity) :type (:type entity))]
+    (assert-gallifrey gallifrey-host "aai" (if (= entity-type :vertex)
+                                             {:meta {:key key :operation operation} :body (generate-string properties)}
+                                             {:meta {:key key :operation operation} :body (generate-string (conj properties (flatten-entry entity :source) (flatten-entry entity :target)))}))))
diff --git a/src/chameleon/config.clj b/src/chameleon/config.clj
new file mode 100644
index 0000000..4982f4a
--- /dev/null
+++ b/src/chameleon/config.clj
@@ -0,0 +1,18 @@
+(ns chameleon.config
+  (:require [integrant.core :as ig]
+            [chameleon.aai-processor :refer :all]))
+
+(defn config
+  [app-config]
+  (let [conf {
+              :chameleon/event
+              {:event-config (assoc-in (:event-config app-config)
+                                       [:aai :processor] from-spike)
+               :gallifrey-host (:gallifrey-host app-config)}
+              :chameleon/handler
+              {:gallifrey-host (:gallifrey-host app-config)}
+              :chameleon/http-server
+              {:port (:http-port app-config)
+               :handler (ig/ref :chameleon/handler)}}]
+    (ig/load-namespaces conf)
+    conf))
diff --git a/src/chameleon/event.clj b/src/chameleon/event.clj
new file mode 100644
index 0000000..8201acb
--- /dev/null
+++ b/src/chameleon/event.clj
@@ -0,0 +1,18 @@
+(ns chameleon.event
+  (:require [chameleon.txform]
+            [chameleon.route]
+            [integrant.core :as ig])
+  (:import [org.onap.aai.event.client DMaaPEventConsumer]))
+
+(defmethod ig/init-key :chameleon/event
+  [_ {:keys [event-config gallifrey-host]}]
+  (let [{:keys [host topic motsid pass consumer-group consumer-id timeout batch-size type processor]} (:aai event-config)
+        event-processor (DMaaPEventConsumer. host topic motsid pass consumer-group consumer-id timeout batch-size type)]
+    (println "Event processor for AAI  created. Starting event polling on " host  topic)
+    (.start (Thread. (fn [] (while true
+                             (let  [it (.iterator (.consume event-processor))]
+                               (println "Polling...")
+                               (while (.hasNext it)
+                                 (let [event (.next it)]
+                                   (processor gallifrey-host event))))))))
+    ))
diff --git a/src/chameleon/handler.clj b/src/chameleon/handler.clj
new file mode 100644
index 0000000..7a4a5fe
--- /dev/null
+++ b/src/chameleon/handler.clj
@@ -0,0 +1,61 @@
+(ns chameleon.handler
+  (:require [chameleon.route :as c-route]
+            [chameleon.aai-processor]
+            [utilis.map :refer [map-vals compact]]
+            [liberator.core :refer [defresource]]
+            [compojure.core :refer [GET PUT PATCH ANY defroutes]]
+            [compojure.route :refer [resources]]
+            [ring.util.response :refer [resource-response content-type]]
+            [ring.middleware.defaults :refer [wrap-defaults api-defaults]]
+            [ring.middleware.anti-forgery :refer [wrap-anti-forgery]]
+            [ring.middleware.session :refer [wrap-session]]
+            [cheshire.core :as json]
+            [clj-time.format :as tf]
+            [integrant.core :as ig]))
+
+(declare handler)
+
+(defonce ^:private g-host (atom nil))
+
+(defmethod ig/init-key :chameleon/handler  [_ {:keys [gallifrey-host]}]
+  (reset! g-host gallifrey-host)
+  handler)
+
+(defmethod ig/halt-key! :chameleon/handler  [_ _]
+  (reset! g-host nil))
+
+(declare serialize de-serialize)
+
+(defresource entity-endpoint [id]
+  :allowed-methods [:get]
+  :available-media-types ["application/json"]
+  :exists? (fn [ctx]
+             (let [resource (-> (c-route/query @g-host id (-> ctx :request :params :t-k)))]
+               (when (= (:status resource) 200)
+                 {::resource (-> resource :body json/parse-string (dissoc "_meta") (chameleon.aai-processor/from-gallifrey))})))
+  :existed? (fn [ctx]
+              (when-let [status (-> (c-route/query @g-host id (-> ctx :request :params :t-k)) :status)]
+                (= status 410)))
+  :handle-ok ::resource)
+
+(defroutes app-routes
+  (GET "/entity/:id" [id] (entity-endpoint id))
+  (resources "/"))
+
+(def handler
+  (-> app-routes
+      (wrap-defaults api-defaults)))
+
+
+;;; Implementation
+
+(defn- serialize
+  [e]
+  (compact
+   (update e :_meta #(map-vals
+                      (fn [m]
+                        (map-vals str m)) %))))
+
+(defn- de-serialize
+  [e]
+  e)
diff --git a/src/chameleon/http_server.clj b/src/chameleon/http_server.clj
new file mode 100644
index 0000000..cf8ae07
--- /dev/null
+++ b/src/chameleon/http_server.clj
@@ -0,0 +1,9 @@
+(ns chameleon.http-server
+  (:require [org.httpkit.server :refer [run-server]]
+            [integrant.core :as ig]))
+
+(defmethod ig/init-key :chameleon/http-server  [_ {:keys [port handler]}]
+  (run-server handler {:port port}))
+
+(defmethod ig/halt-key! :chameleon/http-server  [_ server]
+  (server :timeout 100))
diff --git a/src/chameleon/route.clj b/src/chameleon/route.clj
new file mode 100644
index 0000000..2b30f42
--- /dev/null
+++ b/src/chameleon/route.clj
@@ -0,0 +1,71 @@
+(ns chameleon.route
+  (:require [org.httpkit.client :as kitclient]))
+
+(defn- interpret-response
+  "Print out the response from the Gallifrey server"
+  [key response]
+  (let [{:keys [status body]}@response]
+    (println "Response for request with key " key " resulted in status " status
+             " with body " body )))
+
+(defn query
+  "Retrieve an entity referenced by id at the provided host. Optionally provide
+  a time 't-k' that defines a query based on when the system knew about the
+  state of the entity."
+  [host key & [k]]
+  @(kitclient/request {
+                       :url (str "https://" host "/entity/" key)
+                       :method :get
+                       :query-params (if-let [t-k k] {"t-k" t-k})
+                       :insecure? true
+                       :keepalive 300
+                       :timeout 1000}))
+
+(defn assert-create
+  "Creates an entity in Gallifrey with an initial set of assertions coming from the provided payload"
+  [host actor key payload]
+  (print "Final: " payload)
+  (kitclient/request {
+                      :url (str "https://" host "/entity/" key)
+                      :method :put
+                      :query-params {"actor" actor "create" "true"}
+                      :body payload
+                      :insecure? true
+                      :keepalive 300
+                      :timeout 1000}))
+
+(defn assert-update
+  "Update an entity in Gallifrey with a set of assertions coming from the provided payload"
+  [host actor key payload]
+  (kitclient/request {
+                      :url (str "https://" host "/entity/" key)
+                      :method :put
+                      :query-params {"actor" actor "changes-only" "true"}
+                      :body payload
+                      :insecure? true
+                      :keepalive 300
+                      :timeout 1000}))
+
+(defn assert-delete
+  "Assert a deletion for an entity in Gallifrey based on the provided key."
+  [host actor key]
+  (kitclient/request {
+                      :url (str "https://" host "/entity/" key)
+                      :method :delete
+                      :query-params {"actor" actor}
+                      :insecure? true
+                      :keepalive 300
+                      :timeout 1000}))
+
+(defn assert-gallifrey [host actor payload]
+  "Propagates an assertion to Gallifrey based off of an event payload coming in from the event service."
+  (let [{:keys [meta body]} payload
+        {:keys [key operation]} meta]
+    (println operation " entity with key " key)
+    (interpret-response key (case operation
+                              "CREATE"
+                              (assert-create host actor key body)
+                              "UPDATE"
+                              (assert-update host actor key body)
+                              "DELETE"
+                              (assert-delete host actor key)))))
diff --git a/src/chameleon/txform.clj b/src/chameleon/txform.clj
new file mode 100644
index 0000000..95f357f
--- /dev/null
+++ b/src/chameleon/txform.clj
@@ -0,0 +1,19 @@
+(ns chameleon.txform
+  (:require [cheshire.core :refer :all]
+            [clojure.string :as str]))
+
+(defn map-keywords
+  "Maps all string based keys to keywords"
+  [kmap]
+  (into {} (for [[key value] kmap] [(keyword key) value])))
+
+(defn flatten-key
+  "Maps a parent-child pair to a period separated keyword"
+  [parent child]
+  (keyword (str (name parent) "." (name child))))
+
+(defn flatten-entry
+  "Flattens a nested map entry to a period separated keyword entry"
+  [map key]
+  (reduce #(assoc %1 (flatten-key key (first %2)) (second %2))
+          {} (seq (key map))))