Support backup and recovery of db vars

telegrambots-abilities/src/main/java/org/telegram/abilitybots/api/db/BackupVar.java

@@ -0,0 +1,45 @@
+package org.telegram.abilitybots.api.db;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.google.common.base.MoreObjects;
+
+import java.util.Objects;
+
+public class BackupVar<T> {
+  @JsonProperty("var")
+  private final T var;
+
+  private BackupVar(T var) {
+    this.var = var;
+  }
+
+  @JsonCreator
+  public static <R> BackupVar<R> createVar(@JsonProperty("var") R var) {
+    return new BackupVar<>(var);
+  }
+
+  public T var() {
+    return var;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    BackupVar<?> backupVar = (BackupVar<?>) o;
+    return Objects.equals(var, backupVar.var);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(var);
+  }
+
+  @Override
+  public String toString() {
+    return MoreObjects.toStringHelper(this)
+        .add("var", var)
+        .toString();
+  }
+}

telegrambots-abilities/src/main/java/org/telegram/abilitybots/api/db/MapDBContext.java

@@ -12,12 +12,7 @@ import org.mapdb.Serializer;
 import org.telegram.abilitybots.api.util.Pair;
 
 import java.io.IOException;
-import java.util.Collection;
+import java.util.*;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.StringJoiner;
 
 import static com.google.common.collect.Lists.newArrayList;
 import static com.google.common.collect.Sets.newHashSet;
@@ -188,15 +183,15 @@ public class MapDBContext implements DBContext {
         return Pair.of(entry.getKey(), newArrayList((List) struct));
       else if (struct instanceof Map)
         return Pair.of(entry.getKey(), new BackupMap((Map) struct));
-      else
+      else if (struct instanceof Atomic.Var)
-        return Pair.of(entry.getKey(), struct);
+        return Pair.of(entry.getKey(), BackupVar.createVar(((Atomic.Var) struct).get()));
+      return Pair.of(entry.getKey(), struct);
     }).collect(toMap(pair -> (String) pair.a(), Pair::b));
   }
 
   private void doRecover(Map<String, Object> backupData) {
     clear();
     backupData.forEach((name, value) -> {
-
       if (value instanceof Set) {
         Set entrySet = (Set) value;
         getSet(name).addAll(entrySet);
@@ -206,6 +201,8 @@ public class MapDBContext implements DBContext {
       } else if (value instanceof List) {
         List entryList = (List) value;
         getList(name).addAll(entryList);
+      } else if (value instanceof BackupVar) {
+        getVar(name).set(((BackupVar) value).var());
       } else {
         log.error(format("Unable to identify object type during DB recovery, entry name: %s", name));
       }

telegrambots-abilities/src/test/java/org/telegram/abilitybots/api/db/MapDBContextTest.java

@@ -12,6 +12,7 @@ import java.util.Set;
 
 import static com.google.common.collect.Maps.newHashMap;
 import static com.google.common.collect.Sets.newHashSet;
+import static com.google.common.collect.Sets.toImmutableEnumSet;
 import static java.lang.String.format;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -38,6 +39,24 @@ class MapDBContextTest {
     db.close();
   }
 
+  @Test
+  void canRecoverVar() {
+    Var<String> test = db.getVar(TEST);
+    String val = "abilitybot";
+    test.set(val);
+
+    Object backup = db.backup();
+    db.clear();
+    // db.clear does not clear atomic variables
+    // TODO: get clear to remove all non-collection variables in DB
+    test.set("somevalue");
+    boolean recovered = db.recover(backup);
+    String recoveredVal = db.<String>getVar(TEST).get();
+
+    assertTrue(recovered, "Could not recover JSON backup file");
+    assertEquals(val, recoveredVal, "Could not properly recover val from Var in DB");
+  }
+
   @Test
   void canRecoverDB() {
     Map<Integer, User> users = db.getMap(USERS);