Add update_time to SQLRemoteDocumentCache schema

Author: schmidt-sebastian

firebase-firestore/src/main/java/com/google/firebase/firestore/local/SQLiteRemoteDocumentCache.java

@@ -24,6 +24,7 @@
 import com.google.firebase.firestore.model.DocumentKey;
 import com.google.firebase.firestore.model.MaybeDocument;
 import com.google.firebase.firestore.model.ResourcePath;
+import com.google.firebase.firestore.model.SnapshotVersion;
 import com.google.firebase.firestore.util.BackgroundQueue;
 import com.google.firebase.firestore.util.Executors;
 import com.google.protobuf.InvalidProtocolBufferException;
@@ -51,13 +52,16 @@ final class SQLiteRemoteDocumentCache implements RemoteDocumentCache {
   @Override
   public void add(MaybeDocument maybeDocument) {
     String path = pathForKey(maybeDocument.getKey());
+    SnapshotVersion snapshotVersion = maybeDocument.getVersion();
     MessageLite message = serializer.encodeMaybeDocument(maybeDocument);
 
     statsCollector.recordRowsWritten(STATS_TAG, 1);
 
     db.execute(
-        "INSERT OR REPLACE INTO remote_documents (path, contents) VALUES (?, ?)",
+        "INSERT OR REPLACE INTO remote_documents (path, snapshot_version_micros, contents) "
+            + "VALUES (?, ?, ?)",
         path,
+        snapshotVersion.toMicroseconds(),
         message.toByteArray());
 
     db.getIndexManager().addToCollectionParentIndex(maybeDocument.getKey().getPath().popLast());

firebase-firestore/src/main/java/com/google/firebase/firestore/local/SQLiteSchema.java

@@ -46,7 +46,7 @@ class SQLiteSchema {
    * The version of the schema. Increase this by one for each migration added to runMigrations
    * below.
    */
-  static final int VERSION = 8;
+  static final int VERSION = 9;
   // Remove this constant and increment VERSION to enable indexing support
   static final int INDEXING_SUPPORT_VERSION = VERSION + 1;
 
@@ -127,6 +127,10 @@ void runMigrations(int fromVersion, int toVersion) {
       createV8CollectionParentsIndex();
     }
 
+    if (fromVersion < 9 && toVersion >= 9) {
+      addUpdateTime();
+    }
+
     /*
      * Adding a new migration? READ THIS FIRST!
      *
@@ -351,6 +355,12 @@ private void addSequenceNumber() {
     }
   }
 
+  private void addUpdateTime() {
+    if (!tableContainsColumn("remote_documents", "snapshot_version_micros")) {
+      db.execSQL("ALTER TABLE remote_documents ADD COLUMN snapshot_version_micros INTEGER");
+    }
+  }
+
   /**
    * Ensures that each entry in the remote document cache has a corresponding sentinel row. Any
    * entries that lack a sentinel row are given one with the sequence number set to the highest

firebase-firestore/src/main/java/com/google/firebase/firestore/model/SnapshotVersion.java

@@ -15,6 +15,7 @@
 package com.google.firebase.firestore.model;
 
 import com.google.firebase.Timestamp;
+import java.util.concurrent.TimeUnit;
 
 /**
  * A version of a document in Firestore. This corresponds to the version timestamp, such as
@@ -36,6 +37,12 @@ public Timestamp getTimestamp() {
     return timestamp;
   }
 
+  /** Returns the microseconds since EPOCH that this snapshot version represents. * */
+  public long toMicroseconds() {
+    return TimeUnit.MICROSECONDS.convert(timestamp.getSeconds(), TimeUnit.SECONDS)
+        + TimeUnit.MICROSECONDS.convert(timestamp.getNanoseconds(), TimeUnit.NANOSECONDS);
+  }
+
   @Override
   public int compareTo(SnapshotVersion other) {
     return timestamp.compareTo(other.timestamp);