Mongo

modAionBase/src/org/aion/base/db/IDatabase.java

@@ -146,12 +146,13 @@ public interface IDatabase {
     boolean isAutoCommitEnabled();
 
     /**
-     * Indicates if database persists to disk. Returns a value, regardless of database is opened
-     * (persistence vs in-memory for DB shall be configured upon instantiation of IDatabase)
+     * Indicates the method of persistence this database uses. Whether it's written
+     * to disk, only held in memory, or stored inside a database engine's proprietary
+     * format.
      *
-     * @return {@code true} if data is persistent, {@code false} otherwise
+     * @return The method of persistence this database uses.
      */
-    boolean isPersistent();
+    PersistenceMethod getPersistenceMethod();
 
     /**
      * Used to validate if the DB file(s) has been created on disk. Can be used any time during this

modAionBase/src/org/aion/base/db/PersistenceMethod.java

@@ -0,0 +1,14 @@
+package org.aion.base.db;
+
+public enum PersistenceMethod {
+    UNKNOWN,
+
+    // The data isn't actually persisted but just stored temporarily in memory
+    IN_MEMORY,
+
+    // The data is stored in a file directory
+    FILE_BASED,
+
+    // The data is stored in the proprietary format of a database management system
+    DBMS
+}

modAionImpl/src/org/aion/zero/impl/db/AionRepositoryImpl.java

@@ -82,13 +82,13 @@ protected AionRepositoryImpl(IRepositoryConfig repoConfig) {
     private static class AionRepositoryImplHolder {
         // configuration
         private static CfgAion config = CfgAion.inst();
+
         // repository singleton instance
         private static final AionRepositoryImpl inst =
-                new AionRepositoryImpl(
-                        new RepositoryConfig(
-                                config.getDatabasePath(),
-                                ContractDetailsAion.getInstance(),
-                                config.getDb()));
+                new AionRepositoryImpl(new RepositoryConfig(
+                    config.getDatabasePath(),
+                    ContractDetailsAion.getInstance(),
+                    config.getDb()));
     }
 
     public static AionRepositoryImpl inst() {

modAionImpl/src/org/aion/zero/impl/db/PendingBlockStore.java

@@ -129,7 +129,7 @@ public PendingBlockStore(final Properties _props) throws InvalidFilePathExceptio
 
         // check for database persistence requirements
         DBVendor vendor = DBVendor.fromString(local.getProperty(Props.DB_TYPE));
-        if (vendor.getPersistence()) {
+        if (vendor.isFileBased()) {
             File pbFolder =
                     new File(local.getProperty(Props.DB_PATH), local.getProperty(Props.DB_NAME));
 

modDbImpl/build.gradle

@@ -4,6 +4,15 @@ configurations {
     testClassesOut
 }
 
+
+sourceSets {
+    test {
+        resources {
+            srcDirs = ['test_resources']
+        }
+    }
+}
+
 dependencies {
     compile project(':modAionBase')
     compile project(':modLogger')
@@ -12,6 +21,8 @@ dependencies {
     compile group: 'org.ethereum', name: 'leveldbjni-all', version: '1.18.3'
     compile group: 'org.rocksdb', name: 'rocksdbjni', version: '5.11.3'
     compile group: 'com.h2database', name: 'h2-mvstore', version: '1.4.196'
+    compile group: 'org.mongodb', name: 'mongo-java-driver', version: '3.8.2'
+
 
     testCompile 'junit:junit:4.12'
     testCompile 'com.google.truth:truth:0.42'

modDbImpl/src/module-info.java

@@ -6,6 +6,7 @@
     requires rocksdbjni;
     requires h2.mvstore;
     requires com.google.common;
+    requires mongo.java.driver;
 
     exports org.aion.db.impl;
     exports org.aion.db.impl.leveldb;

modDbImpl/src/org/aion/db/generic/DatabaseWithCache.java

@@ -46,6 +46,7 @@
 import java.util.Optional;
 import java.util.Set;
 import org.aion.base.db.IByteArrayKeyValueDatabase;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.base.util.ByteArrayWrapper;
 import org.aion.db.impl.AbstractDB;
 import org.aion.log.AionLoggerFactory;
@@ -291,8 +292,8 @@ public boolean isAutoCommitEnabled() {
     }
 
     @Override
-    public boolean isPersistent() {
-        return database.isPersistent();
+    public PersistenceMethod getPersistenceMethod() {
+        return database.getPersistenceMethod();
     }
 
     @Override
@@ -505,10 +506,11 @@ public void deleteBatch(Collection<byte[]> keys) {
 
     @Override
     public void drop() {
-        check();
+        if (this.isOpen()) {
+            this.loadingCache.invalidateAll();
+            this.dirtyEntries.clear();
+        }
 
-        this.loadingCache.invalidateAll();
-        this.dirtyEntries.clear();
         this.database.drop();
     }
 

modDbImpl/src/org/aion/db/generic/LockedDatabase.java

@@ -30,6 +30,7 @@
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import org.aion.base.db.IByteArrayKeyValueDatabase;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.log.AionLoggerFactory;
 import org.aion.log.LogEnum;
 import org.slf4j.Logger;
@@ -168,9 +169,9 @@ public boolean isAutoCommitEnabled() {
     }
 
     @Override
-    public boolean isPersistent() {
+    public PersistenceMethod getPersistenceMethod() {
         // no locks because the persistence flag never changes
-        return database.isPersistent();
+        return database.getPersistenceMethod();
     }
 
     @Override

modDbImpl/src/org/aion/db/generic/TimedDatabase.java

@@ -28,6 +28,7 @@
 import java.util.Optional;
 import java.util.Set;
 import org.aion.base.db.IByteArrayKeyValueDatabase;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.base.util.Hex;
 import org.aion.log.AionLoggerFactory;
 import org.aion.log.LogEnum;
@@ -135,9 +136,9 @@ public boolean isAutoCommitEnabled() {
     }
 
     @Override
-    public boolean isPersistent() {
+    public PersistenceMethod getPersistenceMethod() {
         // no locks because the persistence flag never changes
-        return database.isPersistent();
+        return database.getPersistenceMethod();
     }
 
     @Override

modDbImpl/src/org/aion/db/impl/AbstractDB.java

@@ -44,6 +44,7 @@
 import java.util.Optional;
 import java.util.stream.Stream;
 import org.aion.base.db.IByteArrayKeyValueDatabase;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.base.util.ByteArrayWrapper;
 import org.aion.log.AionLoggerFactory;
 import org.aion.log.LogEnum;
@@ -109,6 +110,7 @@ public void compact() {
 
     @Override
     public void drop() {
+        boolean wasOpen = isOpen();
         close();
 
         try (Stream<Path> stream = Files.walk(new File(path).toPath())) {
@@ -117,7 +119,9 @@ public void drop() {
             LOG.error("Unable to delete path due to: ", e);
         }
 
-        open();
+        if (wasOpen) {
+            open();
+        }
     }
 
     @Override
@@ -169,9 +173,9 @@ public boolean isAutoCommitEnabled() {
     }
 
     @Override
-    public boolean isPersistent() {
-        // always persistent when not overwritten by the class
-        return true;
+    public PersistenceMethod getPersistenceMethod() {
+        // Default to file-based since most of our dbs are that
+        return PersistenceMethod.FILE_BASED;
     }
 
     /**

modDbImpl/src/org/aion/db/impl/DBVendor.java

@@ -37,23 +37,26 @@
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.db.impl.rocksdb.RocksDBWrapper;
 
 // @ThreadSafe
 public enum DBVendor {
 
     /** Used in correlation with implementations of {@link IDriver}. */
-    UNKNOWN("unknown", false), //
+    UNKNOWN("unknown", PersistenceMethod.UNKNOWN), //
     /** Using an instance of {@link org.aion.db.impl.leveldb.LevelDB}. */
-    LEVELDB("leveldb", true), //
+    LEVELDB("leveldb", PersistenceMethod.FILE_BASED), //
     /** Using an instance of {@link RocksDBWrapper}. */
-    ROCKSDB("rocksdb", true),
+    ROCKSDB("rocksdb", PersistenceMethod.FILE_BASED),
     /** Using an instance of {@link org.aion.db.impl.h2.H2MVMap}. */
-    H2("h2", true), //
+    H2("h2", PersistenceMethod.FILE_BASED), //
+    /** Using an instance of {@Link org.aion.db.impl.mongodb.MongoDB} */
+    MONGODB("mongodb", PersistenceMethod.DBMS),
     /** Using an instance of {@link org.aion.db.impl.mockdb.MockDB}. */
-    MOCKDB("mockdb", false),
+    MOCKDB("mockdb", PersistenceMethod.IN_MEMORY),
     /** Using an instance of {@link org.aion.db.impl.mockdb.PersistentMockDB}. */
-    PERSISTENTMOCKDB("persistentmockdb", false);
+    PERSISTENTMOCKDB("persistentmockdb", PersistenceMethod.FILE_BASED);
 
     private static final Map<String, DBVendor> stringToTypeMap = new ConcurrentHashMap<>();
 
@@ -65,12 +68,12 @@ public enum DBVendor {
 
     /* map implemented using concurrent hash map */
     private static final List<DBVendor> driverImplementations =
-            List.of(LEVELDB, ROCKSDB, H2, MOCKDB);
+            List.of(LEVELDB, ROCKSDB, H2, MOCKDB, MONGODB);
 
     private final String value;
-    private final boolean persistence;
+    private final PersistenceMethod persistence;
 
-    DBVendor(final String value, final boolean persistent) {
+    DBVendor(final String value, final PersistenceMethod persistent) {
         this.value = value;
         this.persistence = persistent;
     }
@@ -94,14 +97,23 @@ public String toValue() {
     }
 
     /**
-     * Check whether the DB provided by the vendor is intended to be persistent.
+     * Gets the persistence method of this database vendor
      *
-     * @return {@code true} if the DB provider is intended to be persistent
+     * @return The persistence method of the database
      */
-    public boolean getPersistence() {
+    public PersistenceMethod getPersistence() {
         return this.persistence;
     }
 
+    /**
+     * Gets Whether or not this database uses file-based persistence
+     *
+     * @return Whether or not this database uses file-based persistence
+     */
+    public boolean isFileBased() {
+        return this.persistence == PersistenceMethod.FILE_BASED;
+    }
+
     /** @return {@code false} for a DBVendor with an undefined driver implementation */
     public static boolean hasDriverImplementation(DBVendor v) {
         return driverImplementations.contains(v);

modDbImpl/src/org/aion/db/impl/DatabaseFactory.java

@@ -33,6 +33,7 @@
 import org.aion.db.impl.leveldb.LevelDB;
 import org.aion.db.impl.leveldb.LevelDBConstants;
 import org.aion.db.impl.mockdb.MockDB;
+import org.aion.db.impl.mongodb.MongoDB;
 import org.aion.db.impl.mockdb.PersistentMockDB;
 import org.aion.db.impl.rocksdb.RocksDBConstants;
 import org.aion.db.impl.rocksdb.RocksDBWrapper;
@@ -214,6 +215,10 @@ private static AbstractDB connectBasic(Properties info) {
                 {
                     return new H2MVMap(dbName, dbPath, enableDbCache, enableDbCompression);
                 }
+            case MONGODB:
+                {
+                    return new MongoDB(dbName, dbPath);
+                }
             default:
                 break;
         }

modDbImpl/src/org/aion/db/impl/mockdb/MockDB.java

@@ -28,6 +28,7 @@
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.base.util.ByteArrayWrapper;
 import org.aion.db.impl.AbstractDB;
 
@@ -80,8 +81,9 @@ public boolean isOpen() {
     }
 
     @Override
-    public boolean isPersistent() {
-        return false;
+    public PersistenceMethod getPersistenceMethod() {
+        // MockDB doesn't persist anything to disk, so it's type is IN_MEMORY
+        return PersistenceMethod.IN_MEMORY;
     }
 
     @Override

modDbImpl/src/org/aion/db/impl/mockdb/PersistentMockDB.java

@@ -32,6 +32,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
+import org.aion.base.db.PersistenceMethod;
 import org.aion.base.util.ByteArrayWrapper;
 
 /**
@@ -111,8 +112,9 @@ private static final byte[] convertToByteArray(String byteArrayString) {
      *     open and saved to disk at close.
      */
     @Override
-    public boolean isPersistent() {
-        return true;
+    public PersistenceMethod getPersistenceMethod() {
+        // return file-based so file cleanup / setup can proceed as expected
+        return PersistenceMethod.FILE_BASED;
     }
 
     /** @implNote Returns false because data is saved to disk only at close. */