chat, data, utils: add implementation of simple preview caching

src/status_im/chat/handlers/commands.cljs

@@ -1,13 +1,15 @@
 (ns status-im.chat.handlers.commands
-  (:require [re-frame.core :refer [enrich after dispatch]]
+  (:require [cljs.reader :as reader]
+            [clojure.string :as str]
+            [re-frame.core :refer [enrich after dispatch]]
+            [status-im.data-store.messages :as messages]
             [status-im.utils.handlers :as handlers]
             [status-im.components.status :as status]
             [status-im.chat.constants :as const]
             [status-im.commands.utils :as cu]
             [status-im.i18n :as i18n]
             [status-im.utils.platform :as platform]
-            [taoensso.timbre :as log]
-            [clojure.string :as str]))
+            [taoensso.timbre :as log]))
 
 (defn generate-context [{:keys [contacts current-account-id chats] :as db} chat-id to]
   (merge {:platform platform/platform
@@ -38,11 +40,15 @@
                 params   {:parameters params
                           :context    (generate-context db chat-id to)}
                 callback #(let [result (get-in % [:result :returned])
-                                result (if (:markup result)
+                                result' (if (:markup result)
                                          (update result :markup cu/generate-hiccup)
-                                         result)]
-                            (dispatch [:set-in [:message-data data-type message-id] result])
-                            (when on-requested (on-requested result)))]
+                                         result)] 
+                            (dispatch [:set-in [:message-data data-type message-id] result'])
+                            (when (= :preview data-type)
+                              ;; update message in realm with serialized preview
+                              (messages/update {:message-id message-id
+                                                :preview (prn-str result)}))
+                            (when on-requested (on-requested result')))]
             ;chat-id path params callback lock? type
             (status/call-jail {:jail-id  jail-id'
                                :path     path
@@ -64,4 +70,12 @@
     (fn [db [_ {:keys [message-id] :as message}]]
       (let [previews (get-in db [:message-data :preview])]
         (when-not (contains? previews message-id)
-          (dispatch [:request-command-data message :preview]))))))
+          (let [{serialized-preview :preview} (messages/get-by-id message-id)]
+            ;; if preview is already cached in db, do not request it from jail
+            ;; and write it directly to message-data path
+            (if serialized-preview
+              (dispatch [:set-in [:message-data :preview message-id]
+                         (-> serialized-preview
+                             reader/read-string
+                             (update :markup cu/generate-hiccup))])
+              (dispatch [:request-command-data message :preview]))))))))

src/status_im/data_store/messages.cljs

@@ -2,6 +2,7 @@
   (:require [status-im.data-store.realm.messages :as data-store]
             [clojure.string :refer [join split]]
             [status-im.utils.random :refer [timestamp]]
+            [status-im.utils.utils :refer [update-if-present]]
             [clojure.walk :refer [stringify-keys keywordize-keys]]
             [cljs.reader :refer [read-string]]
             [status-im.constants :as c])
@@ -111,10 +112,10 @@
                            :timestamp (timestamp)})]
       (data-store/save message'))))
 
-(defn update
+(defn update 
   [{:keys [message-id] :as message}]
   (when (data-store/exists? message-id)
-    (let [message (clojure.core/update message :user-statuses vals)]
+    (let [message (update-if-present message :user-statuses vals)]
       (data-store/save message))))
 
 (defn delete-by-chat-id [chat-id]

src/status_im/utils/utils.cljs

@@ -20,11 +20,11 @@
    (.alert (.-Alert rn-dependencies/react-native)
            title
            content
-           ; Styles are only relevant on iOS. On Android first button is 'neutral' and second is 'positive'
+           ;; Styles are only relevant on iOS. On Android first button is 'neutral' and second is 'positive'
            (clj->js
-             (vector (merge {:text (label :t/cancel) :style "cancel"}
-                            (when on-cancel {:onPress on-cancel}))
-                     {:text (or s "OK") :onPress on-accept :style "destructive"})))))
+            (vector (merge {:text (label :t/cancel) :style "cancel"}
+                           (when on-cancel {:onPress on-cancel}))
+                    {:text (or s "OK") :onPress on-accept :style "destructive"})))))
 
 (defn http-post
   ([action data on-success]
@@ -49,7 +49,7 @@
 
 (defn http-get
   ([url on-success on-error]
-    (http-get url nil on-success on-error))
+   (http-get url nil on-success on-error))
   ([url valid-response? on-success on-error]
    (-> (.fetch js/window url (clj->js {:method  "GET"
                                        :headers {"Cache-Control" "no-cache"}}))
@@ -72,9 +72,13 @@
                    (fn [error]
                      (show-popup "Error" (str error))))))))
 
-(defn truncate-str [s max]
-  (if (and (< max (count s)) s)
-    (str (subs s 0 (- max 3)) "...")
+(defn truncate-str
+  "Given string and max threshold, trims the string to threshold length with `...`
+  appended to end if length of the string exceeds max threshold, returns the same
+  string if threshold is not exceeded"
+  [s threshold]
+  (if (and s (< threshold (count s)))
+    (str (subs s 0 (- threshold 3)) "...")
     s))
 
 (defn clean-text [s]
@@ -84,14 +88,13 @@
       (str/trim)))
 
 (defn first-index
-  [cond coll]
-  (loop [index 0
-         cond cond
-         coll coll]
-    (when (seq coll)
-      (if (cond (first coll))
-        index
-        (recur (inc index) cond (next coll))))))
+  "Returns first index in coll where predicate on coll element is truthy"
+  [pred coll]
+  (->> coll
+       (keep-indexed (fn [idx e]
+                       (when (pred e)
+                         idx)))
+       first))
 
 (defn hash-tag? [s]
   (= \# (first s)))
@@ -105,3 +108,11 @@
         (vreset! called? true)
         (apply f args)
         nil))))
+
+(defn update-if-present
+  "Like regular `clojure.core/update` but returns original map if update key is not present"
+  [m k f & args]
+  (if (contains? m k)
+    (apply update m k f args)
+    m))
+

test/cljs/status_im/test/utils/utils.cljs

@@ -1,6 +1,6 @@
 (ns status-im.test.utils.utils
-    (:require [cljs.test :refer-macros [deftest is]]
-              [status-im.utils.utils :as u]))
+  (:require [cljs.test :refer-macros [deftest is]]
+            [status-im.utils.utils :as u]))
 
 (deftest wrap-as-call-once-test
   (let [count (atom 0)]
@@ -9,4 +9,30 @@
         (is (nil? (f)))
         (is (= 1 @count))
         (is (nil? (f)))
-        (is (= 1 @count))))))
+        (is (= 1 @count))))))
+
+(deftest truncate-str-test
+  (is (= (u/truncate-str "Long string" 7) "Long...")) ; threshold is less then string length
+  (is (= (u/truncate-str "Long string" 11) "Long string")) ; threshold is the same as string length
+  (is (= (u/truncate-str "Long string" 20) "Long string"))) ; threshold is more then string length
+
+(deftest clean-text-test
+  (is (= (u/clean-text "Hello! \n\r") "Hello!")
+      (= (u/clean-text "Hello!") "Hello!")))
+
+(deftest first-index-test
+  (is (= 2 (u/first-index (partial = :test)
+                          '(:a :b :test :c :test))))
+  (is (= nil (u/first-index (partial = :test)
+                            '(:a :b :c)))))
+
+(deftest hash-tag?-test
+  (is (u/hash-tag? "#clojure"))
+  (is (not (u/hash-tag? "clojure")))
+  (is (not (u/hash-tag? "clo#jure")))
+  (is (not (u/hash-tag? "clojure#"))))
+
+(deftest update-if-present-test
+  (is (= {:a 1} (u/update-if-present {:a 0} :a inc)))
+  (is (= {:a 2} (u/update-if-present {:a 0} :a + 2)))
+  (is (= {:a 0} (u/update-if-present {:a 0} :b inc))))