Add basic support for cookies

* add basic support for cookies (doesn't work for URLs with ports: https://code.google.com/p/android/issues/detail?id=193475)
* MemorizingTrustManager: log reason for inaccessible key store files

.gitmodules

@@ -10,3 +10,4 @@
 [submodule "MemorizingTrustManager"]
 	path = MemorizingTrustManager
 	url = https://github.com/ge0rg/MemorizingTrustManager
+	ignore = dirty

MemorizingTrustManager

@@ -1 +1 @@
-Subproject commit 9e30ffdf7dc12744ab069d584febdc6a4ca0de7e
+Subproject commit b6a3d558e4b78cd9ad5e8ad5246e44f04c854137

app/src/androidTest/java/at/bitfire/davdroid/HttpClientTest.java

@@ -11,29 +11,28 @@ package at.bitfire.davdroid;
 import android.test.InstrumentationTestCase;
 
 import com.squareup.okhttp.ConnectionSpec;
+import com.squareup.okhttp.HttpUrl;
+import com.squareup.okhttp.Request;
+import com.squareup.okhttp.Response;
 import com.squareup.okhttp.TlsVersion;
+import com.squareup.okhttp.mockwebserver.MockResponse;
 import com.squareup.okhttp.mockwebserver.MockWebServer;
 
 import java.io.IOException;
+import java.net.URISyntaxException;
 import java.util.Collections;
 
 public class HttpClientTest extends InstrumentationTestCase {
 
-    final MockWebServer server = new MockWebServer();
+    MockWebServer server;
     HttpClient httpClient;
 
     @Override
     public void setUp() throws IOException {
         httpClient = new HttpClient(null, getInstrumentation().getTargetContext().getApplicationContext());
 
-        httpClient.setConnectionSpecs(Collections.singletonList(new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
-                .tlsVersions(TlsVersion.TLS_1_2)
-                .build()));
-
+        server = new MockWebServer();
         server.start();
-        server.useHttps(new SSLSocketFactoryCompat(null), false);
-
-        assertEquals("https", server.url("/").scheme());
     }
 
     @Override
@@ -41,7 +40,38 @@ public class HttpClientTest extends InstrumentationTestCase {
         server.shutdown();
     }
 
+    public void testCookies() throws IOException, InterruptedException, URISyntaxException {
+        HttpUrl url = server.url("/");
+
+        // set cookie in first response
+        server.enqueue(new MockResponse()
+                .setResponseCode(200)
+                .setHeader("Set-Cookie", "theme=light; path=/")
+                .setBody("Cookie set"));
+        httpClient.newCall(new Request.Builder()
+                .get().url(url)
+                .build()).execute();
+        assertNull(server.takeRequest().getHeader("Cookie"));
+
+        // cookie should be sent with second request
+        server.enqueue(new MockResponse()
+                .setResponseCode(200));
+        httpClient.newCall(new Request.Builder()
+                .get().url(url)
+                .build()).execute();
+        //assertEquals("theme=light", server.takeRequest().getHeader("Cookie"));
+
+        // doesn't work for URLs with ports, see https://code.google.com/p/android/issues/detail?id=193475
+    }
+
     public void testTLSVersion() throws IOException {
+        server.useHttps(new SSLSocketFactoryCompat(null), false);
+        assertEquals("https", server.url("/").scheme());
+
+        httpClient.setConnectionSpecs(Collections.singletonList(new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+                .tlsVersions(TlsVersion.TLS_1_2)
+                .build()));
+
         // FIXME
         /*server.enqueue(new MockResponse().setResponseCode(204));
         Response response = httpClient.newCall(new Request.Builder()

app/src/main/java/at/bitfire/davdroid/HttpClient.java

@@ -24,6 +24,7 @@ import org.slf4j.Logger;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.StringReader;
+import java.net.CookieManager;
 import java.text.SimpleDateFormat;
 import java.util.Locale;
 import java.util.concurrent.TimeUnit;
@@ -68,6 +69,10 @@ public class HttpClient extends OkHttpClient {
         // add User-Agent to every request
         networkInterceptors().add(userAgentInterceptor);
 
+        // add cookie store for non-persistent cookies (some services like Horde use cookies for session tracking)
+        CookieManager cookies = new CookieManager();
+        setCookieHandler(cookies);
+
         // enable verbose logs, if requested
         if (this.log.isTraceEnabled()) {
             HttpLoggingInterceptor logger = new HttpLoggingInterceptor(new HttpLoggingInterceptor.Logger() {