Harden ApiProvider for concurrent modifications and add unit tests

2 files changed, 100 insertions, 4 deletions

diff --git a/app/src/main/java/it/niedermann/owncloud/notes/persistence/ApiProvider.java b/app/src/main/java/it/niedermann/owncloud/notes/persistence/ApiProvider.java
index 1afd8875..6b851ddb 100644
--- a/app/src/main/java/it/niedermann/owncloud/notes/persistence/ApiProvider.java
+++ b/app/src/main/java/it/niedermann/owncloud/notes/persistence/ApiProvider.java
@@ -16,8 +16,8 @@ import com.nextcloud.android.sso.api.NextcloudAPI;
 import com.nextcloud.android.sso.model.SingleSignOnAccount;
 
 import java.util.Calendar;
-import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import it.niedermann.owncloud.notes.persistence.sync.CapabilitiesDeserializer;
 import it.niedermann.owncloud.notes.persistence.sync.NotesAPI;
@@ -40,10 +40,10 @@ public class ApiProvider {
 
     private static final String API_ENDPOINT_OCS = "/ocs/v2.php/cloud/";
 
-    private static final Map<String, NextcloudAPI> API_CACHE = new HashMap<>();
+    private static final Map<String, NextcloudAPI> API_CACHE = new ConcurrentHashMap<>();
 
-    private static final Map<String, OcsAPI> API_CACHE_OCS = new HashMap<>();
-    private static final Map<String, NotesAPI> API_CACHE_NOTES = new HashMap<>();
+    private static final Map<String, OcsAPI> API_CACHE_OCS = new ConcurrentHashMap<>();
+    private static final Map<String, NotesAPI> API_CACHE_NOTES = new ConcurrentHashMap<>();
 
     public static ApiProvider getInstance() {
         return INSTANCE;
diff --git a/app/src/test/java/it/niedermann/owncloud/notes/persistence/ApiProviderTest.java b/app/src/test/java/it/niedermann/owncloud/notes/persistence/ApiProviderTest.java
new file mode 100644
index 00000000..2bffda88
--- /dev/null
+++ b/app/src/test/java/it/niedermann/owncloud/notes/persistence/ApiProviderTest.java
@@ -0,0 +1,96 @@
+package it.niedermann.owncloud.notes.persistence;
+
+import android.os.Build;
+
+import androidx.arch.core.executor.testing.InstantTaskExecutorRule;
+import androidx.test.core.app.ApplicationProvider;
+
+import com.nextcloud.android.sso.model.SingleSignOnAccount;
+
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+import org.robolectric.annotation.Config;
+
+import it.niedermann.owncloud.notes.persistence.sync.NotesAPI;
+import it.niedermann.owncloud.notes.persistence.sync.OcsAPI;
+import it.niedermann.owncloud.notes.shared.model.ApiVersion;
+
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNotSame;
+import static org.junit.Assert.assertSame;
+
+@RunWith(RobolectricTestRunner.class)
+@Config(sdk = {Build.VERSION_CODES.P})
+public class ApiProviderTest {
+
+    @Rule
+    public InstantTaskExecutorRule instantTaskExecutorRule = new InstantTaskExecutorRule();
+
+    private ApiProvider apiProvider;
+    private SingleSignOnAccount ssoAccount;
+    private SingleSignOnAccount secondSsoAccount;
+
+    @Before
+    public void setup() {
+        apiProvider = ApiProvider.getInstance();
+        ssoAccount = new SingleSignOnAccount("one", "eins", "1", "example.com", "");
+        secondSsoAccount = new SingleSignOnAccount("two", "zwei", "2", "example.org", "");
+    }
+
+    @Test
+    public void testGetOcsAPI() {
+        OcsAPI api = apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), ssoAccount);
+
+        assertNotNull(api);
+        assertSame(api, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), ssoAccount));
+        assertNotSame(api, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), secondSsoAccount));
+
+        apiProvider.invalidateAPICache(ssoAccount);
+
+        final OcsAPI newApi = apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), ssoAccount);
+
+        assertNotSame("After invalidating the cache, a new API instance is returned", api, newApi);
+
+        api = newApi;
+
+        assertSame(api, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), ssoAccount));
+        assertNotSame("A new instance should be returned when another SingleSignOn account is provided",
+                api, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), secondSsoAccount));
+
+        apiProvider.invalidateAPICache();
+
+        assertNotSame(api, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), ssoAccount));
+        assertNotSame(newApi, apiProvider.getOcsAPI(ApplicationProvider.getApplicationContext(), secondSsoAccount));
+    }
+
+    @Test
+    public void testGetNotesAPI() {
+        final NotesAPI notesAPI = apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_0_2);
+
+        assertNotNull(notesAPI);
+
+        assertSame("Before a manual invalidation, the returned Notes API will be the same instance",
+                notesAPI, apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_0_2));
+        assertSame("Before a manual invalidation, the returned Notes API will be the same instance, no matter which preferred version is passed",
+                notesAPI, apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_1_0));
+
+        apiProvider.invalidateAPICache();
+
+        final NotesAPI newNotesAPI = apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_1_0);
+
+        assertNotSame("After a manual invalidation, the returned Notes API will be a new instance",
+                notesAPI, newNotesAPI);
+        assertSame("Before a manual invalidation, the returned Notes API will be the same instance, no matter which preferred version is passed",
+                newNotesAPI, apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_0_2));
+        assertNotSame("Before a manual invalidation, the returned Notes API will be a different instance, even if the preferred version is the same, if the ssoAccount is different",
+                newNotesAPI, apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), secondSsoAccount, ApiVersion.API_VERSION_0_2));
+
+        apiProvider.invalidateAPICache(ssoAccount);
+
+        assertNotSame("After a manual invalidation, the returned Notes API will be a new instance",
+                newNotesAPI, apiProvider.getNotesAPI(ApplicationProvider.getApplicationContext(), ssoAccount, ApiVersion.API_VERSION_0_2));
+    }
+}
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