added remove from shared prefs

Author: inventvenkat

src/Presto/Core/Flow.purs

@@ -7,6 +7,6 @@ module Presto.Core.Flow ( module Presto.Core.Language.Runtime.API
 
 import Presto.Core.Language.Runtime.API (APIRunner, runAPIInteraction)
 import Presto.Core.Language.Runtime.Interpreter (Runtime(..), PermissionRunner(..), PermissionCheckRunner, PermissionTakeRunner, UIRunner, run)
-import Presto.Core.Types.Language.Flow (Flow, callAPI, evalUI, forkUI, runUI, showUI, get, set, load, save, fork, launch, doAff, await, await', delay, oneOf)
+import Presto.Core.Types.Language.Flow (Flow, callAPI, evalUI, forkUI, runUI, showUI, get, set, load, save, delete, fork, launch, doAff, await, await', delay, oneOf)
 import Presto.Core.Types.Language.Interaction (class Interact, Interaction, defaultInteract, request)
 import Presto.Core.Types.Language.Storage (class Serializable, Key)

src/Presto/Core/Language/Runtime/Interpreter.purs

@@ -26,7 +26,7 @@ import Foreign.Object as Object
 import Global.Unsafe (unsafeStringify)
 
 import Presto.Core.Language.Runtime.API (APIRunner, runAPIInteraction)
-import Presto.Core.LocalStorage (getValueFromLocalStore, setValueToLocalStore)
+import Presto.Core.LocalStorage (getValueFromLocalStore, setValueToLocalStore, deleteValueFromLocalStore)
 import Presto.Core.Types.Language.Flow (ErrorHandler(..), Flow, FlowMethod, FlowMethodF(..), FlowWrapper(..), Store(..), Control(..))
 import Presto.Core.Types.Language.Interaction (InteractionF(..), Interaction, ForeignOut(..))
 import Presto.Core.Types.Language.Storage (Key)
@@ -105,6 +105,14 @@ interpret _ (Set LocalStore key value next) = do
 interpret _ (Set InMemoryStore key value next) = do
   updateState key value *> pure next
 
+interpret _ (Delete LocalStore key next) = do
+  lift $ deleteValueFromLocalStore key
+  pure next
+
+interpret _ (Delete InMemoryStore key next) = do
+  _ <- Object.delete key <$> readState
+  pure next
+
 interpret r (Fork flow nextF) = forkFlow r flow >>= (pure <<< nextF)
 
 interpret _ (DoAff aff nextF) = lift aff >>= (pure <<< nextF)

src/Presto/Core/LocalStorage/LocalStorage.js

@@ -5,3 +5,7 @@ exports.getValueFromLocalStoreImpl = function(key) {
 exports.setValueToLocalStoreImpl = function(key, value) {
   return JBridge.setInSharedPrefs(key, value);
 };
+
+exports.deleteValueFromLocalStoreImpl = function(key){
+  JBridge.removeDataFromSharedPrefs(key);
+};

src/Presto/Core/LocalStorage/LocalStorage.purs

@@ -19,9 +19,17 @@ foreign import setValueToLocalStoreImpl ::
     String
     Unit
 
+foreign import deleteValueFromLocalStoreImpl ::
+  EffectFn1
+    String
+    Unit
+
 getValueFromLocalStore :: String -> Aff (Maybe String)
 getValueFromLocalStore k = let v = liftEffect $ runEffectFn1 getValueFromLocalStoreImpl k
                                in ifM ((==) "__failed" <$> v) (pure Nothing) (Just <$> v)
 
 setValueToLocalStore :: String -> String -> Aff Unit
 setValueToLocalStore k v = liftEffect $ runEffectFn2 setValueToLocalStoreImpl k v
+
+deleteValueFromLocalStore :: String -> Aff Unit
+deleteValueFromLocalStore k = liftEffect $ runEffectFn1 deleteValueFromLocalStoreImpl k

src/Presto/Core/Types/Language/Flow.purs

@@ -36,6 +36,7 @@ data FlowMethodF a s
   | CallAPI (Interaction (APIResult s)) (APIResult s -> a)
   | Get Store Key (Maybe String -> a)
   | Set Store Key String a
+  | Delete Store Key a
   | Fork (Flow s) (Control s -> a)
   | DoAff (Aff s) (s -> a)
   | Await (Control s) (s -> a)
@@ -63,6 +64,10 @@ getS key = wrap $ Get InMemoryStore key identity
 setS :: Key -> String -> Flow Unit
 setS key val = wrap $ Set InMemoryStore key val unit
 
+-- | Deletes a string value from sharedprefs using key.
+delete :: Key -> Flow Unit
+delete key = wrap $ Delete LocalStore key unit
+
 -- | Gets some string from localStorage by key
 loadS :: Key -> Flow (Maybe String)
 loadS key = wrap $ Get LocalStore key identity