Fix AWSKeyValueStore for crashes in Encryption Key management (#1130)

* [Core] Improve error handling in AWSKeyValueStore

* [Core] Remove unused variables

* [AWSMobileClient] Add tests for persistence and app restartability

* [AWSMobileClient] Fix issue where hostedUI object is null

* Improve error handling in KeyProvider, AWSKeyValueStore; Add validation check for accessToken

* Improve error handling in KeyProvider, AWSKeyValueStore; Add validation check for accessToken

* Javadoc fixes

* Javadoc fixes

* Javadoc fixes

* Fix LGTM alert

Author: Karthikeyan

.idea/modules.xml

@@ -0,0 +1,5 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.amazonaws.mobileconnectors.cognitoidentityprovider" >
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+</manifest>

aws-android-sdk-cognitoidentityprovider-test/src/androidTest/AndroidManifest.xml

@@ -16,6 +16,7 @@
 package com.amazonaws.mobileconnectors.cognitoidentityprovider;
 
 import android.content.Context;
+import android.os.Build;
 import android.support.test.InstrumentationRegistry;
 import android.support.test.runner.AndroidJUnit4;
 import android.util.Base64;
@@ -30,8 +31,14 @@
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 
+import java.security.KeyStore;
 import java.util.Calendar;
 import java.util.Date;
+import java.util.Enumeration;
+
+import static junit.framework.Assert.assertFalse;
+import static junit.framework.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 @RunWith(AndroidJUnit4.class)
 public abstract class CognitoIdentityProviderUnitTestBase extends AWSTestBase {

aws-android-sdk-cognitoidentityprovider-test/src/androidTest/java/com/amazonaws/mobileconnectors/cognitoidentityprovider/CognitoIdentityProviderUnitTestBase.java

@@ -0,0 +1,166 @@
+/*
+ * Copyright 2019-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package com.amazonaws.mobileconnectors.cognitoidentityprovider;
+
+import android.content.Context;
+import android.os.Build;
+import android.support.test.InstrumentationRegistry;
+import android.util.Log;
+
+import com.amazonaws.mobileconnectors.cognitoidentityprovider.continuations.AuthenticationContinuation;
+import com.amazonaws.mobileconnectors.cognitoidentityprovider.continuations.AuthenticationDetails;
+import com.amazonaws.mobileconnectors.cognitoidentityprovider.continuations.ChallengeContinuation;
+import com.amazonaws.mobileconnectors.cognitoidentityprovider.continuations.MultiFactorAuthenticationContinuation;
+import com.amazonaws.mobileconnectors.cognitoidentityprovider.handlers.AuthenticationHandler;
+import com.amazonaws.testutils.AWSTestBase;
+
+import org.json.JSONObject;
+
+import java.security.KeyStore;
+import java.security.KeyStoreException;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static junit.framework.Assert.assertFalse;
+import static junit.framework.Assert.assertTrue;
+import static org.junit.Assert.*;
+
+public abstract class CognitoUserPoolsIntegrationTestBase extends AWSTestBase {
+
+    private Context appContext;
+    private CognitoUserPool cognitoUserPool;
+    private String userName;
+    private String password;
+    private String userEmail;
+
+    private JSONObject getPackageConfigure()  {
+        return getPackageConfigure("CognitoUserPools");
+    }
+
+    void setUp() {
+        try {
+            appContext = InstrumentationRegistry.getTargetContext();
+            userName = getPackageConfigure().getString("UserName");
+            password = getPackageConfigure().getString("Password");
+            userEmail = getPackageConfigure().getString("UserEmail");
+
+            cognitoUserPool = new CognitoUserPool(appContext,
+                    getPackageConfigure().getString("UserPoolId"),
+                    getPackageConfigure().getString("AppClientId"),
+                    getPackageConfigure().getString("AppClientSecret"));
+        } catch (Exception ex) {
+            fail("Error in reading CognitoUserPools test configuration. Please check " + super.TEST_CONFIGURATION_FILENAME + " file."
+                    + ex);
+        }
+    }
+
+    void tearDown() {
+        try {
+            cognitoUserPool.awsKeyValueStore.clear();
+        } catch (Exception ex) {
+            ex.printStackTrace();
+            fail ("Error in wiping off data stored on disk by CognitoUserPools." + ex);
+        }
+    }
+
+    CognitoUserSession signIn() {
+        final CountDownLatch signInLatch = new CountDownLatch(1);
+        final ArrayList<CognitoUserSession> listSessions = new ArrayList<CognitoUserSession>();
+
+        cognitoUserPool.getUser(userName).getSession(new AuthenticationHandler() {
+            @Override
+            public void onSuccess(CognitoUserSession userSession, CognitoDevice newDevice) {
+                listSessions.add(userSession);
+                signInLatch.countDown();
+            }
+
+            @Override
+            public void getAuthenticationDetails(AuthenticationContinuation authenticationContinuation, String userId) {
+                AuthenticationDetails authenticationDetails = new AuthenticationDetails(userName, password, null);
+                authenticationContinuation.setAuthenticationDetails(authenticationDetails);
+                authenticationContinuation.continueTask();
+            }
+
+            @Override
+            public void getMFACode(MultiFactorAuthenticationContinuation continuation) {
+                fail("Tests are not configured to work with MFA. " +
+                        "Either create a CognitoUserPool without MFA or update the test.");
+                signInLatch.countDown();
+            }
+
+            @Override
+            public void authenticationChallenge(ChallengeContinuation continuation) {
+                fail("Tests are not configured to work with additional challenges. " +
+                        "Either create a CognitoUserPool without additional challenges or update the test.");
+                signInLatch.countDown();
+            }
+
+            @Override
+            public void onFailure(Exception exception) {
+                fail("Error while signing-in. " + exception.getLocalizedMessage());
+                signInLatch.countDown();
+            }
+        });
+
+        try {
+            signInLatch.await(60, TimeUnit.SECONDS);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        assertEquals(1, listSessions.size());
+
+        return listSessions.get(0);
+    }
+
+    void signOut() {
+        getUser().signOut();
+    }
+
+    CognitoUserPool createCognitoUserPool() {
+        try {
+            return new CognitoUserPool(appContext,
+                    getPackageConfigure().getString("UserPoolId"),
+                    getPackageConfigure().getString("AppClientId"),
+                    getPackageConfigure().getString("AppClientSecret"));
+        } catch (Exception ex) {
+            fail("Error in constructing a CognitoUserPool object.");
+            return null;
+        }
+    }
+
+    public CognitoUserPool getUserPool() {
+        return cognitoUserPool;
+    }
+
+    public CognitoUser getUser() {
+        return cognitoUserPool.getUser(userName);
+    }
+
+    public String getUserName() {
+        return userName;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public String getUserEmail() {
+        return userEmail;
+    }
+}