Add support for remote feature flags.

app/src/main/java/org/thoughtcrime/securesms/ApplicationContext.java

@@ -49,6 +49,7 @@ import org.thoughtcrime.securesms.jobs.FcmRefreshJob;
 import org.thoughtcrime.securesms.jobs.MultiDeviceContactUpdateJob;
 import org.thoughtcrime.securesms.jobs.PushNotificationReceiveJob;
 import org.thoughtcrime.securesms.jobs.StickerPackDownloadJob;
+import org.thoughtcrime.securesms.keyvalue.SignalStore;
 import org.thoughtcrime.securesms.logging.AndroidLogger;
 import org.thoughtcrime.securesms.logging.CustomSignalProtocolLogger;
 import org.thoughtcrime.securesms.logging.Log;
@@ -71,6 +72,7 @@ import org.thoughtcrime.securesms.service.RotateSenderCertificateListener;
 import org.thoughtcrime.securesms.service.RotateSignedPreKeyListener;
 import org.thoughtcrime.securesms.service.UpdateApkRefreshListener;
 import org.thoughtcrime.securesms.stickers.BlessedPacks;
+import org.thoughtcrime.securesms.util.FeatureFlags;
 import org.thoughtcrime.securesms.util.TextSecurePreferences;
 import org.thoughtcrime.securesms.util.Util;
 import org.thoughtcrime.securesms.util.concurrent.SignalExecutors;
@@ -133,6 +135,7 @@ public class ApplicationContext extends MultiDexApplication implements DefaultLi
     initializeBlobProvider();
     initializeCleanup();
     initializeCameraX();
+    FeatureFlags.init();
     NotificationChannels.create(this);
     ProcessLifecycleOwner.get().getLifecycle().addObserver(this);
 

app/src/main/java/org/thoughtcrime/securesms/ApplicationPreferencesActivity.java

@@ -42,7 +42,6 @@ import org.thoughtcrime.securesms.profiles.edit.EditProfileActivity;
 import org.thoughtcrime.securesms.service.KeyCachingService;
 import org.thoughtcrime.securesms.util.DynamicLanguage;
 import org.thoughtcrime.securesms.util.DynamicTheme;
-import org.thoughtcrime.securesms.util.FeatureFlags;
 import org.thoughtcrime.securesms.util.TextSecurePreferences;
 import org.thoughtcrime.securesms.util.ThemeUtil;
 

app/src/main/java/org/thoughtcrime/securesms/GroupMembersDialog.java

@@ -113,7 +113,7 @@ public class GroupMembersDialog extends AsyncTask<Void, Void, List<Recipient>> {
     }
 
     private String getRecipientName(Recipient recipient) {
-      if (FeatureFlags.PROFILE_DISPLAY) return recipient.getDisplayName(context);
+      if (FeatureFlags.profileDisplay()) return recipient.getDisplayName(context);
 
       String name = recipient.toShortString(context);
 

app/src/main/java/org/thoughtcrime/securesms/RecipientPreferenceActivity.java

@@ -434,7 +434,7 @@ public class RecipientPreferenceActivity extends PassphraseRequiredActionBarActi
         colorPreference.setColors(MaterialColors.CONVERSATION_PALETTE.asConversationColorArray(requireActivity()));
         colorPreference.setColor(recipient.getColor().toActionBarColor(requireActivity()));
 
-        if (FeatureFlags.PROFILE_DISPLAY) {
+        if (FeatureFlags.profileDisplay()) {
           aboutPreference.setTitle(recipient.getDisplayName(requireContext()));
           aboutPreference.setSummary(recipient.resolve().getE164().or(""));
         } else {

app/src/main/java/org/thoughtcrime/securesms/VerifyIdentityActivity.java

@@ -275,7 +275,7 @@ public class VerifyIdentityActivity extends PassphraseRequiredActionBarActivity
       byte[] localId;
       byte[] remoteId;
 
-      if (FeatureFlags.UUIDS && recipient.resolve().getUuid().isPresent()) {
+      if (FeatureFlags.uuids() && recipient.resolve().getUuid().isPresent()) {
         Log.i(TAG, "Using UUID (version 2).");
         version  = 2;
         localId  = UuidUtil.toByteArray(TextSecurePreferences.getLocalUuid(requireContext()));

app/src/main/java/org/thoughtcrime/securesms/components/FromTextView.java

@@ -61,7 +61,7 @@ public class FromTextView extends EmojiTextView {
 
     if (recipient.isLocalNumber()) {
       builder.append(getContext().getString(R.string.note_to_self));
-    } else if (!FeatureFlags.PROFILE_DISPLAY && recipient.getName(getContext()) == null && !recipient.getProfileName().isEmpty()) {
+    } else if (!FeatureFlags.profileDisplay() && recipient.getName(getContext()) == null && !recipient.getProfileName().isEmpty()) {
       SpannableString profileName = new SpannableString(" (~" + recipient.getProfileName().toString() + ") ");
       profileName.setSpan(new CenterAlignedRelativeSizeSpan(0.75f), 0, profileName.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
       profileName.setSpan(new TypefaceSpan("sans-serif-light"), 0, profileName.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);

app/src/main/java/org/thoughtcrime/securesms/components/webrtc/WebRtcCallScreen.java

@@ -370,7 +370,7 @@ public class WebRtcCallScreen extends FrameLayout implements RecipientForeverObs
             .diskCacheStrategy(DiskCacheStrategy.ALL)
             .into(this.photo);
 
-    if (FeatureFlags.PROFILE_DISPLAY) {
+    if (FeatureFlags.profileDisplay()) {
       this.name.setText(recipient.getDisplayName(getContext()));
 
       if (recipient.getE164().isPresent()) {

app/src/main/java/org/thoughtcrime/securesms/contacts/ContactsCursorLoader.java

@@ -145,15 +145,15 @@ public class ContactsCursorLoader extends CursorLoader {
       cursorList.addAll(getContactsCursors());
     }
 
-    if (FeatureFlags.USERNAMES && NumberUtil.isVisuallyValidNumberOrEmail(filter)) {
+    if (FeatureFlags.usernames() && NumberUtil.isVisuallyValidNumberOrEmail(filter)) {
       cursorList.add(getPhoneNumberSearchHeaderCursor());
       cursorList.add(getNewNumberCursor());
-    } else if (!FeatureFlags.USERNAMES && NumberUtil.isValidSmsOrEmail(filter)){
+    } else if (!FeatureFlags.usernames() && NumberUtil.isValidSmsOrEmail(filter)){
       cursorList.add(getContactsHeaderCursor());
       cursorList.add(getNewNumberCursor());
     }
 
-    if (FeatureFlags.USERNAMES && UsernameUtil.isValidUsernameForSearch(filter)) {
+    if (FeatureFlags.usernames() && UsernameUtil.isValidUsernameForSearch(filter)) {
       cursorList.add(getUsernameSearchHeaderCursor());
       cursorList.add(getUsernameSearchCursor());
     }

app/src/main/java/org/thoughtcrime/securesms/contacts/sync/DirectoryHelper.java

@@ -17,14 +17,14 @@ public class DirectoryHelper {
 
   @WorkerThread
   public static void refreshDirectory(@NonNull Context context, boolean notifyOfNewUsers) throws IOException {
-    if (FeatureFlags.UUIDS) {
+    if (FeatureFlags.uuids()) {
       // TODO [greyson] Create a DirectoryHelperV2 when appropriate.
       DirectoryHelperV1.refreshDirectory(context, notifyOfNewUsers);
     } else {
       DirectoryHelperV1.refreshDirectory(context, notifyOfNewUsers);
     }
 
-    if (FeatureFlags.STORAGE_SERVICE) {
+    if (FeatureFlags.storageService()) {
       ApplicationDependencies.getJobManager().add(new StorageSyncJob());
     }
   }
@@ -34,14 +34,14 @@ public class DirectoryHelper {
     RegisteredState originalRegisteredState = recipient.resolve().getRegistered();
     RegisteredState newRegisteredState      = null;
 
-    if (FeatureFlags.UUIDS) {
+    if (FeatureFlags.uuids()) {
       // TODO [greyson] Create a DirectoryHelperV2 when appropriate.
       newRegisteredState = DirectoryHelperV1.refreshDirectoryFor(context, recipient, notifyOfNewUsers);
     } else {
       newRegisteredState = DirectoryHelperV1.refreshDirectoryFor(context, recipient, notifyOfNewUsers);
     }
 
-    if (FeatureFlags.STORAGE_SERVICE && newRegisteredState != originalRegisteredState) {
+    if (FeatureFlags.storageService() && newRegisteredState != originalRegisteredState) {
       ApplicationDependencies.getJobManager().add(new StorageSyncJob());
     }
 

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationActivity.java

@@ -2014,7 +2014,7 @@ public class ConversationActivity extends PassphraseRequiredActionBarActivity
   }
 
   private void setGroupShareProfileReminder(@NonNull Recipient recipient) {
-    if (!FeatureFlags.MESSAGE_REQUESTS && recipient.isPushGroup() && !recipient.isProfileSharing()) {
+    if (!FeatureFlags.messageRequests() && recipient.isPushGroup() && !recipient.isProfileSharing()) {
       groupShareProfileView.get().setRecipient(recipient);
       groupShareProfileView.get().setVisibility(View.VISIBLE);
     } else if (groupShareProfileView.resolved()) {

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationFragment.java

@@ -713,7 +713,7 @@ public class ConversationFragment extends Fragment
       setLastSeen(loader.getLastSeen());
     }
 
-    if (FeatureFlags.MESSAGE_REQUESTS) {
+    if (FeatureFlags.messageRequests()) {
       if (!loader.hasSent() && !recipient.get().isSystemContact() && !recipient.get().isProfileSharing() && !recipient.get().isBlocked() && recipient.get().isRegistered()) {
         listener.onMessageRequest();
       } else {
@@ -994,8 +994,8 @@ public class ConversationFragment extends Fragment
 
       if (actionMode != null) return;
 
-      if (FeatureFlags.REACTION_SENDING &&
+      if (FeatureFlags.reactionSending() &&
-          messageRecord.isSecure()      &&
+          messageRecord.isSecure()       &&
           ((ConversationAdapter) list.getAdapter()).getSelectedItems().isEmpty())
       {
         isReacting = true;

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationItem.java

@@ -960,7 +960,7 @@ public class ConversationItem extends LinearLayout implements BindableConversati
   private void setGroupMessageStatus(MessageRecord messageRecord, Recipient recipient) {
     if (groupThread && !messageRecord.isOutgoing()) {
 
-      if (FeatureFlags.PROFILE_DISPLAY) {
+      if (FeatureFlags.profileDisplay()) {
         this.groupSender.setText(recipient.getDisplayName(getContext()));
         this.groupSenderProfileName.setVisibility(View.GONE);
       } else {

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationTitleView.java

@@ -126,7 +126,7 @@ public class ConversationTitleView extends RelativeLayout {
   }
 
   private void setRecipientTitle(Recipient recipient) {
-    if (FeatureFlags.PROFILE_DISPLAY) {
+    if (FeatureFlags.profileDisplay()) {
       if      (recipient.isGroup())       setGroupRecipientTitle(recipient);
       else if (recipient.isLocalNumber()) setSelfTitle();
       else                                setIndividualRecipientTitle(recipient);
@@ -166,7 +166,7 @@ public class ConversationTitleView extends RelativeLayout {
   private void setGroupRecipientTitle(Recipient recipient) {
     String localNumber = TextSecurePreferences.getLocalNumber(getContext());
 
-    if (FeatureFlags.PROFILE_DISPLAY) {
+    if (FeatureFlags.profileDisplay()) {
       this.title.setText(recipient.getDisplayName(getContext()));
     } else {
       this.title.setText(recipient.getName(getContext()));

app/src/main/java/org/thoughtcrime/securesms/database/RecipientDatabase.java

@@ -1209,7 +1209,7 @@ public class RecipientDatabase extends Database {
   }
 
   void markDirty(@NonNull RecipientId recipientId, @NonNull DirtyState dirtyState) {
-    if (!FeatureFlags.STORAGE_SERVICE) return;
+    if (!FeatureFlags.storageService()) return;
 
     ContentValues contentValues = new ContentValues(1);
     contentValues.put(DIRTY, dirtyState.getId());

app/src/main/java/org/thoughtcrime/securesms/dependencies/ApplicationDependencies.java

@@ -69,7 +69,7 @@ public class ApplicationDependencies {
   }
 
   public static synchronized @NonNull KeyBackupService getKeyBackupService() {
-    if (!FeatureFlags.KBS) throw new AssertionError();
+    if (!FeatureFlags.kbs()) throw new AssertionError();
     return getSignalServiceAccountManager().getKeyBackupService(IasKeyStore.getIasKeyStore(application),
                                                                 BuildConfig.KEY_BACKUP_ENCLAVE_NAME,
                                                                 BuildConfig.KEY_BACKUP_MRENCLAVE,

app/src/main/java/org/thoughtcrime/securesms/jobs/JobManagerFactories.java

@@ -75,6 +75,7 @@ public final class JobManagerFactories {
       put(RefreshAttributesJob.KEY,                  new RefreshAttributesJob.Factory());
       put(RefreshOwnProfileJob.KEY,                  new RefreshOwnProfileJob.Factory());
       put(RefreshPreKeysJob.KEY,                     new RefreshPreKeysJob.Factory());
+      put(RemoteConfigRefreshJob.KEY,                new RemoteConfigRefreshJob.Factory());
       put(RequestGroupInfoJob.KEY,                   new RequestGroupInfoJob.Factory());
       put(RetrieveProfileAvatarJob.KEY,              new RetrieveProfileAvatarJob.Factory());
       put(RetrieveProfileJob.KEY,                    new RetrieveProfileJob.Factory());

app/src/main/java/org/thoughtcrime/securesms/jobs/RemoteConfigRefreshJob.java

@@ -0,0 +1,66 @@
+package org.thoughtcrime.securesms.jobs;
+
+import androidx.annotation.NonNull;
+
+import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
+import org.thoughtcrime.securesms.jobmanager.Data;
+import org.thoughtcrime.securesms.jobmanager.Job;
+import org.thoughtcrime.securesms.keyvalue.SignalStore;
+import org.thoughtcrime.securesms.util.FeatureFlags;
+import org.thoughtcrime.securesms.util.TextSecurePreferences;
+import org.whispersystems.signalservice.api.push.exceptions.PushNetworkException;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+
+public class RemoteConfigRefreshJob extends BaseJob {
+
+  public static final String KEY = "RemoteConfigRefreshJob";
+
+  public RemoteConfigRefreshJob() {
+    this(new Job.Parameters.Builder()
+                           .setQueue("RemoteConfigRefreshJob")
+                           .setMaxInstances(1)
+                           .setMaxAttempts(Parameters.UNLIMITED)
+                           .setLifespan(TimeUnit.DAYS.toMillis(1))
+                           .build());
+  }
+
+  private RemoteConfigRefreshJob(@NonNull Parameters parameters) {
+    super(parameters);
+  }
+
+  @Override
+  public @NonNull Data serialize() {
+    return Data.EMPTY;
+  }
+
+  @Override
+  public @NonNull String getFactoryKey() {
+    return KEY;
+  }
+
+  @Override
+  protected void onRun() throws Exception {
+    Map<String, Boolean> config = ApplicationDependencies.getSignalServiceAccountManager().getRemoteConfig();
+    FeatureFlags.updateDiskCache(config);
+    SignalStore.setRemoteConfigLastFetchTime(System.currentTimeMillis());
+  }
+
+  @Override
+  protected boolean onShouldRetry(@NonNull Exception e) {
+    return e instanceof PushNetworkException;
+  }
+
+  @Override
+  public void onFailure() {
+  }
+
+  public static final class Factory implements Job.Factory<RemoteConfigRefreshJob> {
+    @Override
+    public @NonNull RemoteConfigRefreshJob create(@NonNull Parameters parameters, @NonNull Data data) {
+      return new RemoteConfigRefreshJob(parameters);
+    }
+  }
+}

app/src/main/java/org/thoughtcrime/securesms/jobs/RetrieveProfileJob.java

@@ -102,7 +102,7 @@ public class RetrieveProfileJob extends BaseJob {
 
     setProfileName(recipient, profile.getName());
     setProfileAvatar(recipient, profile.getAvatar());
-    if (FeatureFlags.USERNAMES) setUsername(recipient, profile.getUsername());
+    if (FeatureFlags.usernames()) setUsername(recipient, profile.getUsername());
     setProfileCapabilities(recipient, profile.getCapabilities());
     setIdentityKey(recipient, profile.getIdentityKey());
     setUnidentifiedAccessMode(recipient, profile.getUnidentifiedAccess(), profile.isUnrestrictedUnidentifiedAccess());

app/src/main/java/org/thoughtcrime/securesms/jobs/StorageForcePushJob.java

@@ -67,7 +67,7 @@ public class StorageForcePushJob extends BaseJob {
 
   @Override
   protected void onRun() throws IOException, RetryLaterException {
-    if (!FeatureFlags.STORAGE_SERVICE) throw new AssertionError();
+    if (!FeatureFlags.storageService()) throw new AssertionError();
 
     MasterKey kbsMasterKey = SignalStore.kbsValues().getPinBackedMasterKey();
 

app/src/main/java/org/thoughtcrime/securesms/jobs/StorageSyncJob.java

@@ -79,7 +79,7 @@ public class StorageSyncJob extends BaseJob {
 
   @Override
   protected void onRun() throws IOException, RetryLaterException {
-    if (!FeatureFlags.STORAGE_SERVICE) throw new AssertionError();
+    if (!FeatureFlags.storageService()) throw new AssertionError();
 
     try {
       boolean needsMultiDeviceSync = performSync();

app/src/main/java/org/thoughtcrime/securesms/keyvalue/SignalStore.java

@@ -1,5 +1,7 @@
 package org.thoughtcrime.securesms.keyvalue;
 
+import android.content.Context;
+
 import androidx.annotation.NonNull;
 
 import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
@@ -10,12 +12,32 @@ import org.thoughtcrime.securesms.logging.SignalUncaughtExceptionHandler;
  */
 public final class SignalStore {
 
+  private static final String REMOTE_CONFIG                 = "remote_config";
+  private static final String REMOTE_CONFIG_LAST_FETCH_TIME = "remote_config_last_fetch_time";
+
   private SignalStore() {}
 
   public static KbsValues kbsValues() {
     return new KbsValues(getStore());
   }
 
+  public static String getRemoteConfig() {
+    return getStore().getString(REMOTE_CONFIG, null);
+  }
+
+  public static void setRemoteConfig(String value) {
+    putString(REMOTE_CONFIG, value);
+  }
+
+  public static long getRemoteConfigLastFetchTime() {
+    return getStore().getLong(REMOTE_CONFIG_LAST_FETCH_TIME, 0);
+  }
+
+  public static void setRemoteConfigLastFetchTime(long time) {
+    putLong(REMOTE_CONFIG_LAST_FETCH_TIME, time);
+  }
+
+
   /**
    * Ensures any pending writes are finished. Only intended to be called by
    * {@link SignalUncaughtExceptionHandler}.

app/src/main/java/org/thoughtcrime/securesms/lock/RegistrationLockDialog.java

@@ -126,7 +126,7 @@ public final class RegistrationLockDialog {
         dialog.dismiss();
         RegistrationLockReminders.scheduleReminder(context, true);
 
-        if (FeatureFlags.KBS) {
+        if (FeatureFlags.kbs()) {
           Log.i(TAG, "Pin V1 successfully remembered, scheduling a migration to V2");
           ApplicationDependencies.getJobManager().add(new RegistrationPinV2MigrationJob());
         }
@@ -201,7 +201,7 @@ public final class RegistrationLockDialog {
           @Override
           protected Boolean doInBackground(Void... voids) {
             try {
-              if (!FeatureFlags.KBS) {
+              if (!FeatureFlags.kbs()) {
                 Log.i(TAG, "Setting V1 pin");
                 SignalServiceAccountManager accountManager = ApplicationDependencies.getSignalServiceAccountManager();
                 accountManager.setPin(pinValue);
@@ -282,7 +282,7 @@ public final class RegistrationLockDialog {
           @Override
           protected Boolean doInBackground(Void... voids) {
             try {
-              if (!FeatureFlags.KBS) {
+              if (!FeatureFlags.kbs()) {
                 Log.i(TAG, "Removing v1 registration lock pin from server");
                 ApplicationDependencies.getSignalServiceAccountManager().removeV1Pin();
               } else {

app/src/main/java/org/thoughtcrime/securesms/logsubmit/SubmitLogFragment.java

@@ -52,6 +52,8 @@ import androidx.fragment.app.Fragment;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
+import com.annimon.stream.Stream;
+
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.thoughtcrime.securesms.ApplicationContext;
@@ -61,6 +63,7 @@ import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
 import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.logsubmit.util.Scrubber;
 import org.thoughtcrime.securesms.util.BucketInfo;
+import org.thoughtcrime.securesms.util.FeatureFlags;
 import org.thoughtcrime.securesms.util.FrameRateTracker;
 import org.thoughtcrime.securesms.util.TextSecurePreferences;
 import org.thoughtcrime.securesms.util.Util;
@@ -111,6 +114,7 @@ public class SubmitLogFragment extends Fragment {
   private static final String HEADER_POWER       = "========== POWER ==========";
   private static final String HEADER_THREADS     = "===== BLOCKED THREADS =====";
   private static final String HEADER_PERMISSIONS = "======= PERMISSIONS =======";
+  private static final String HEADER_FLAGS       = "====== FEATURE FLAGS ======";
   private static final String HEADER_LOGCAT      = "========== LOGCAT =========";
   private static final String HEADER_LOGGER      = "========== LOGGER =========";
 
@@ -411,6 +415,11 @@ public class SubmitLogFragment extends Fragment {
                    .append(buildBlockedThreads())
                    .append("\n\n\n");
 
+      stringBuilder.append(HEADER_FLAGS)
+                   .append("\n\n")
+                   .append(buildFlags())
+                   .append("\n\n\n");
+
       stringBuilder.append(HEADER_PERMISSIONS)
                    .append("\n\n")
                    .append(buildPermissions(context))
@@ -628,6 +637,28 @@ public class SubmitLogFragment extends Fragment {
     return out;
   }
 
+  private static CharSequence buildFlags() {
+    StringBuilder        out          = new StringBuilder();
+    Map<String, Boolean> remote       = FeatureFlags.getRemoteValues();
+    Map<String, Boolean> forced       = FeatureFlags.getForcedValues();
+    int                  remoteLength = Stream.of(remote.keySet()).map(String::length).max(Integer::compareTo).orElse(0);
+    int                  forcedLength = Stream.of(forced.keySet()).map(String::length).max(Integer::compareTo).orElse(0);
+
+    out.append("-- Remote\n");
+    for (Map.Entry<String, Boolean> entry : remote.entrySet()) {
+      out.append(Util.rightPad(entry.getKey(), remoteLength)).append(": ").append(entry.getValue()).append("\n");
+    }
+    out.append("\n");
+
+    out.append("-- Forced\n");
+    for (Map.Entry<String, Boolean> entry : forced.entrySet()) {
+      out.append(Util.rightPad(entry.getKey(), forcedLength)).append(": ").append(entry.getValue()).append("\n");
+    }
+
+    return out;
+  }
+
+
   private static Iterable<String> getSupportedAbis() {
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
       return Arrays.asList(Build.SUPPORTED_ABIS);

app/src/main/java/org/thoughtcrime/securesms/migrations/RegistrationPinV2MigrationJob.java

@@ -55,7 +55,7 @@ public final class RegistrationPinV2MigrationJob extends BaseJob {
 
   @Override
   protected void onRun() throws IOException, UnauthenticatedResponseException, KeyBackupServicePinException {
-    if (!FeatureFlags.KBS) {
+    if (!FeatureFlags.kbs()) {
       Log.i(TAG, "Not migrating pin to KBS");
       return;
     }

app/src/main/java/org/thoughtcrime/securesms/profiles/edit/EditProfileFragment.java

@@ -203,7 +203,7 @@ public class EditProfileFragment extends Fragment {
     this.usernameLabel      = view.findViewById(R.id.profile_overview_username_label);
     this.nextIntent         = getArguments().getParcelable(NEXT_INTENT);
 
-    if (FeatureFlags.USERNAMES && getArguments().getBoolean(DISPLAY_USERNAME, false)) {
+    if (FeatureFlags.usernames() && getArguments().getBoolean(DISPLAY_USERNAME, false)) {
       username.setVisibility(View.VISIBLE);
       usernameEditButton.setVisibility(View.VISIBLE);
       usernameLabel.setVisibility(View.VISIBLE);

app/src/main/java/org/thoughtcrime/securesms/recipients/Recipient.java

@@ -167,7 +167,7 @@ public class Recipient {
       } else if (!recipient.isRegistered()) {
         db.markRegistered(recipient.getId());
 
-        if (FeatureFlags.UUIDS) {
+        if (FeatureFlags.uuids()) {
           Log.i(TAG, "No UUID! Scheduling a fetch.");
           ApplicationDependencies.getJobManager().add(new DirectoryRefreshJob(recipient, false));
         }
@@ -175,7 +175,7 @@ public class Recipient {
 
       return resolved(recipient.getId());
     } else if (uuid != null) {
-      if (FeatureFlags.UUIDS || e164 != null) {
+      if (FeatureFlags.uuids() || e164 != null) {
         RecipientId id = db.getOrInsertFromUuid(uuid);
         db.markRegistered(id, uuid);
 
@@ -193,7 +193,7 @@ public class Recipient {
       if (!recipient.isRegistered()) {
         db.markRegistered(recipient.getId());
 
-        if (FeatureFlags.UUIDS) {
+        if (FeatureFlags.uuids()) {
           Log.i(TAG, "No UUID! Scheduling a fetch.");
           ApplicationDependencies.getJobManager().add(new DirectoryRefreshJob(recipient, false));
         }
@@ -247,7 +247,7 @@ public class Recipient {
     if (UuidUtil.isUuid(identifier)) {
       UUID uuid = UuidUtil.parseOrThrow(identifier);
 
-      if (FeatureFlags.UUIDS) {
+      if (FeatureFlags.uuids()) {
         id = db.getOrInsertFromUuid(uuid);
       } else {
         Optional<RecipientId> possibleId = db.getByUuid(uuid);
@@ -383,8 +383,8 @@ public class Recipient {
    */
   @Deprecated
   public @NonNull String toShortString(@NonNull Context context) {
-    if (FeatureFlags.PROFILE_DISPLAY) return getDisplayName(context);
+    if (FeatureFlags.profileDisplay()) return getDisplayName(context);
-    else                    return Optional.fromNullable(getName(context)).or(getSmsAddress()).or("");
+    else                               return Optional.fromNullable(getName(context)).or(getSmsAddress()).or("");
   }
 
   public @NonNull String getDisplayName(@NonNull Context context) {
@@ -408,7 +408,7 @@ public class Recipient {
   }
 
   public @NonNull Optional<String> getUsername() {
-    if (FeatureFlags.USERNAMES) {
+    if (FeatureFlags.usernames()) {
       return Optional.fromNullable(username);
     } else {
       return Optional.absent();
@@ -529,7 +529,7 @@ public class Recipient {
   }
 
   public @Nullable String getCustomLabel() {
-    if (FeatureFlags.PROFILE_DISPLAY) throw new AssertionError("This method should never be called if PROFILE_DISPLAY is enabled.");
+    if (FeatureFlags.profileDisplay()) throw new AssertionError("This method should never be called if PROFILE_DISPLAY is enabled.");
     return customLabel;
   }
 
@@ -655,10 +655,10 @@ public class Recipient {
    * @return True if this recipient can support receiving UUID-only messages, otherwise false.
    */
   public boolean isUuidSupported() {
-    if (FeatureFlags.USERNAMES) {
+    if (FeatureFlags.usernames()) {
       return true;
     } else {
-      return FeatureFlags.UUIDS && uuidSupported;
+      return FeatureFlags.uuids() && uuidSupported;
     }
   }
 

app/src/main/java/org/thoughtcrime/securesms/recipients/RecipientUtil.java

@@ -44,7 +44,7 @@ public class RecipientUtil {
       throw new AssertionError(recipient.getId() + " - No UUID or phone number!");
     }
 
-    if (FeatureFlags.UUIDS && !recipient.getUuid().isPresent()) {
+    if (FeatureFlags.uuids() && !recipient.getUuid().isPresent()) {
       Log.i(TAG, recipient.getId() + " is missing a UUID...");
       try {
         RegisteredState state = DirectoryHelper.refreshDirectoryFor(context, recipient, false);
@@ -110,7 +110,7 @@ public class RecipientUtil {
 
   @WorkerThread
   public static boolean isRecipientMessageRequestAccepted(@NonNull Context context, @Nullable Recipient recipient) {
-    if (recipient == null || !FeatureFlags.MESSAGE_REQUESTS) return true;
+    if (recipient == null || !FeatureFlags.messageRequests()) return true;
 
     Recipient resolved = recipient.resolve();
 

app/src/main/java/org/thoughtcrime/securesms/registration/service/CodeVerificationRequest.java

@@ -55,7 +55,7 @@ public final class CodeVerificationRequest {
 
   static TokenResponse getToken(@Nullable String basicStorageCredentials) throws IOException {
     if (basicStorageCredentials == null) return null;
-    if (!FeatureFlags.KBS) return null;
+    if (!FeatureFlags.kbs()) return null;
     return ApplicationDependencies.getKeyBackupService().getToken(basicStorageCredentials);
   }
 
@@ -214,7 +214,7 @@ public final class CodeVerificationRequest {
       //noinspection deprecation Only acceptable place to write the old pin enabled state.
       TextSecurePreferences.setV1RegistrationLockEnabled(context, pin != null);
       if (pin != null) {
-        if (FeatureFlags.KBS) {
+        if (FeatureFlags.kbs()) {
           Log.i(TAG, "Pin V1 successfully entered during registration, scheduling a migration to Pin V2");
           ApplicationDependencies.getJobManager().add(new RegistrationPinV2MigrationJob());
         }
@@ -230,7 +230,7 @@ public final class CodeVerificationRequest {
   }
 
   private static void repostPinToResetTries(@NonNull Context context, @Nullable String pin, @NonNull RegistrationLockData kbsData) {
-    if (!FeatureFlags.KBS) return;
+    if (!FeatureFlags.kbs()) return;
 
     if (pin == null) return;
 
@@ -264,7 +264,7 @@ public final class CodeVerificationRequest {
       return null;
     }
 
-    if (!FeatureFlags.KBS) {
+    if (!FeatureFlags.kbs()) {
       Log.w(TAG, "User appears to have a KBS pin, but this build has KBS off.");
       return null;
     }

app/src/main/java/org/thoughtcrime/securesms/util/FeatureFlags.java

@@ -1,28 +1,192 @@
 package org.thoughtcrime.securesms.util;
 
+import android.text.TextUtils;
+
+import androidx.annotation.NonNull;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.thoughtcrime.securesms.dependencies.ApplicationDependencies;
+import org.thoughtcrime.securesms.jobs.RemoteConfigRefreshJob;
+import org.thoughtcrime.securesms.keyvalue.SignalStore;
+import org.thoughtcrime.securesms.logging.Log;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.TreeMap;
+import java.util.concurrent.TimeUnit;
+
 /**
- * A location for constants that allows us to turn features on and off during development.
+ * A location for flags that can be set locally and remotely. These flags can guard features that
- * After a feature has been launched, the flag should be removed.
+ * are not yet ready to be activated.
+ *
+ * When creating a new flag:
+ * - Create a new string constant using {@link #generateKey(String)})
+ * - Add a method to retrieve the value using {@link #getValue(String, boolean)}. You can also add
+ *   other checks here, like requiring other flags.
+ * - If you would like to force a value for testing, place an entry in {@link #FORCED_VALUES}. When
+ *   launching a feature that is planned to be updated via a remote config, do not forget to
+ *   remove the entry!
  */
-public class FeatureFlags {
+public final class FeatureFlags {
+
+  private static final String TAG = Log.tag(FeatureFlags.class);
+
+  private static final String PREFIX         = "android.";
+  private static final long   FETCH_INTERVAL = TimeUnit.HOURS.toMillis(2);
+
+  private static final String UUIDS             = generateKey("uuids");
+  private static final String PROFILE_DISPLAY   = generateKey("profileDisplay");
+  private static final String MESSAGE_REQUESTS  = generateKey("messageRequests");
+  private static final String USERNAMES         = generateKey("usernames");
+  private static final String KBS               = generateKey("kbs");
+  private static final String STORAGE_SERVICE   = generateKey("storageService");
+  private static final String REACTION_SENDING  = generateKey("reactionSending");
+
+  /**
+   * Values in this map will take precedence over any value. If you do not wish to have any sort of
+   * override, simply don't put a value in this map. You should never commit additions to this map
+   * for flags that you plan on updating remotely.
+   */
+  private static final Map<String, Boolean> FORCED_VALUES = new HashMap<String, Boolean>() {{
+    put(UUIDS, false);
+    put(PROFILE_DISPLAY, false);
+    put(MESSAGE_REQUESTS, false);
+    put(USERNAMES, false);
+    put(KBS, false);
+    put(STORAGE_SERVICE, false);
+    put(REACTION_SENDING, false);
+  }};
+
+  private static final Map<String, Boolean> REMOTE_VALUES = new HashMap<>();
+
+  private FeatureFlags() {}
+
+  public static void init() {
+    scheduleFetchIfNecessary();
+    REMOTE_VALUES.putAll(parseStoredConfig());
+  }
+
+  public static void updateDiskCache(@NonNull Map<String, Boolean> config) {
+    try {
+      JSONObject filtered = new JSONObject();
+
+      for (Map.Entry<String, Boolean> entry : config.entrySet()) {
+        if (entry.getKey().startsWith(PREFIX)) {
+          filtered.put(entry.getKey(), (boolean) entry.getValue());
+        }
+      }
+
+      SignalStore.setRemoteConfig(filtered.toString());
+    } catch (JSONException e) {
+      throw new AssertionError(e);
+    }
+  }
+
   /** UUID-related stuff that shouldn't be activated until the user-facing launch. */
-  public static final boolean UUIDS = false;
+  public static boolean uuids() {
+    return getValue(UUIDS, false);
+  }
 
   /** Favoring profile names when displaying contacts. */
-  public static final boolean PROFILE_DISPLAY = UUIDS;
+  public static boolean profileDisplay() {
+    return getValue(PROFILE_DISPLAY, false);
+  }
 
   /** MessageRequest stuff */
-  public static final boolean MESSAGE_REQUESTS = UUIDS;
+  public static boolean messageRequests() {
+    return getValue(MESSAGE_REQUESTS, false);
+  }
 
-  /** Creating usernames, sending messages by username. Requires {@link #UUIDS}. */
+  /** Creating usernames, sending messages by username. Requires {@link #uuids()}. */
-  public static final boolean USERNAMES = false;
+  public static boolean usernames() {
+    boolean value = getValue(USERNAMES, false);
+    if (value && !uuids()) throw new MissingFlagRequirementError();
+    return value;
+  }
 
   /** Set or migrate PIN to KBS */
-  public static final boolean KBS = false;
+  public static boolean kbs() {
+    return getValue(KBS, false);
+  }
 
-  /** Storage service. Requires {@link #KBS}. */
+  /** Storage service. Requires {@link #kbs()}. */
-  public static final boolean STORAGE_SERVICE = false;
+  public static boolean storageService() {
+    boolean value = getValue(STORAGE_SERVICE, false);
+    if (value && !kbs()) throw new MissingFlagRequirementError();
+    return value;
+  }
 
   /** Send support for reactions. */
-  public static final boolean REACTION_SENDING = false;
+  public static boolean reactionSending() {
+    return getValue(REACTION_SENDING, false);
+  }
+
+  /** Only for rendering debug info. */
+  public static @NonNull Map<String, Boolean> getRemoteValues() {
+    return new TreeMap<>(REMOTE_VALUES);
+  }
+
+  /** Only for rendering debug info. */
+  public static @NonNull Map<String, Boolean> getForcedValues() {
+    return new TreeMap<>(FORCED_VALUES);
+  }
+
+  private static @NonNull String generateKey(@NonNull String key) {
+    return PREFIX + key;
+  }
+
+  private static boolean getValue(@NonNull String key, boolean defaultValue) {
+    Boolean forced = FORCED_VALUES.get(key);
+    if (forced != null) {
+      return forced;
+    }
+
+    Boolean remote = REMOTE_VALUES.get(key);
+    if (remote != null) {
+      return remote;
+    }
+
+    return defaultValue;
+  }
+
+  private static void scheduleFetchIfNecessary() {
+    long timeSinceLastFetch = System.currentTimeMillis() - SignalStore.getRemoteConfigLastFetchTime();
+
+    if (timeSinceLastFetch > FETCH_INTERVAL) {
+      Log.i(TAG, "Scheduling remote config refresh.");
+      ApplicationDependencies.getJobManager().add(new RemoteConfigRefreshJob());
+    } else {
+      Log.i(TAG, "Skipping remote config refresh. Refreshed " + timeSinceLastFetch + " ms ago.");
+    }
+  }
+
+  private static Map<String, Boolean> parseStoredConfig() {
+    Map<String, Boolean> parsed = new HashMap<>();
+    String               stored = SignalStore.getRemoteConfig();
+
+    if (TextUtils.isEmpty(stored)) {
+      Log.i(TAG, "No remote config stored. Skipping.");
+      return parsed;
+    }
+
+    try {
+      JSONObject       root = new JSONObject(stored);
+      Iterator<String> iter = root.keys();
+
+      while (iter.hasNext()) {
+        String key = iter.next();
+        parsed.put(key, root.getBoolean(key));
+      }
+    } catch (JSONException e) {
+      SignalStore.setRemoteConfig(null);
+      throw new AssertionError("Failed to parse! Cleared storage.");
+    }
+
+    return parsed;
+  }
+
+  private static final class MissingFlagRequirementError extends Error {
+  }
 }

app/src/main/java/org/thoughtcrime/securesms/util/Util.java

@@ -122,6 +122,19 @@ public class Util {
     return sb.toString();
   }
 
+  public static String rightPad(String value, int length) {
+    if (value.length() >= length) {
+      return value;
+    }
+
+    StringBuilder out = new StringBuilder(value);
+    while (out.length() < length) {
+      out.append(" ");
+    }
+
+    return out.toString();
+  }
+
   public static ExecutorService newSingleThreadedLifoExecutor() {
     ThreadPoolExecutor executor = new ThreadPoolExecutor(1, 1, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingLifoQueue<Runnable>());
 

libsignal/service/src/main/java/org/whispersystems/signalservice/api/SignalServiceAccountManager.java

@@ -43,6 +43,7 @@ import org.whispersystems.signalservice.internal.crypto.ProvisioningCipher;
 import org.whispersystems.signalservice.internal.push.ProfileAvatarData;
 import org.whispersystems.signalservice.internal.push.PushServiceSocket;
 import org.whispersystems.signalservice.internal.push.RemoteAttestationUtil;
+import org.whispersystems.signalservice.internal.push.RemoteConfigResponse;
 import org.whispersystems.signalservice.internal.push.http.ProfileCipherOutputStreamFactory;
 import org.whispersystems.signalservice.internal.storage.protos.ManifestRecord;
 import org.whispersystems.signalservice.internal.storage.protos.ReadOperation;
@@ -501,6 +502,16 @@ public class SignalServiceAccountManager {
     }
   }
 
+  public Map<String, Boolean> getRemoteConfig() throws IOException {
+    RemoteConfigResponse response = this.pushServiceSocket.getRemoteConfig();
+    Map<String, Boolean> out      = new HashMap<>();
+
+    for (RemoteConfigResponse.Config config : response.getConfig()) {
+      out.put(config.getName(), config.isEnabled());
+    }
+
+    return out;
+  }
 
 
   public String getNewDeviceVerificationCode() throws IOException {

libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/PushServiceSocket.java

@@ -731,6 +731,11 @@ public class PushServiceSocket {
     }
   }
 
+  public RemoteConfigResponse getRemoteConfig() throws IOException {
+    String response = makeServiceRequest("/v1/config", "GET", null);
+    return JsonUtil.fromJson(response, RemoteConfigResponse.class);
+  }
+
   public void setSoTimeoutMillis(long soTimeoutMillis) {
     this.soTimeoutMillis = soTimeoutMillis;
   }

libsignal/service/src/main/java/org/whispersystems/signalservice/internal/push/RemoteConfigResponse.java

@@ -0,0 +1,30 @@
+package org.whispersystems.signalservice.internal.push;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+import java.util.List;
+
+public class RemoteConfigResponse {
+  @JsonProperty
+  private List<Config> config;
+
+  public List<Config> getConfig() {
+    return config;
+  }
+
+  public static class Config {
+    @JsonProperty
+    private String name;
+
+    @JsonProperty
+    private boolean enabled;
+
+    public String getName() {
+      return name;
+    }
+
+    public boolean isEnabled() {
+      return enabled;
+    }
+  }
+}