Merge pull request #14 from dzlier-gcp/master

Add protection to creating scores from DataSnapshots.

Author: dzlier-gcp

.gitignore

@@ -0,0 +1 @@
+LICENSE.meta

Firebase_Leaderboard/Scripts/LeaderboardController.cs

@@ -262,7 +262,7 @@ private void Update() {
 
  dbref = FirebaseDatabase.DefaultInstance.RootReference;
  initialized = true;
- RefreshScores();
+ refreshScores = true;
  readyToInitialize = false;
  if (FirebaseInitialized != null) {
  FirebaseInitialized(this, null);
@@ -427,6 +427,7 @@ public Task<UserScore> AddScore(UserScore score) {
  return newEntry.SetValueAsync(scoreDict).ContinueWith(task => {
  if (task.Exception != null) {
  Debug.LogWarning("Exception adding score: " + task.Exception);
+ return null;
  }
  if (!task.IsCompleted) {
  return null;
@@ -508,7 +509,10 @@ private void OnScoreAdded(object sender, ChildChangedEventArgs args) {
  return;
  }
 
- var score = new UserScore(args.Snapshot);
+ var score = UserScore.CreateScoreFromRecord(args.Snapshot);
+ if (score == null) {
+ return;
+ }
 
  // Verify that score is within start/end times, and isn't already in TopScores.
  if (TopScores.Contains(score)) {
@@ -577,7 +581,10 @@ private void OnScoreRemoved(object sender, ChildChangedEventArgs args) {
  if (args.Snapshot == null || !args.Snapshot.Exists) {
  return;
  }
- var score = new UserScore(args.Snapshot);
+ var score = UserScore.CreateScoreFromRecord(args.Snapshot);
+ if (score == null) {
+ return;
+ }
  if (TopScores.Contains(score)) {
  TopScores.Remove(score);
  RefreshScores();
@@ -609,7 +616,7 @@ private void GetInitialTopScores(long batchEnd) {
  return;
  }
 
- if (task.Result.ChildrenCount == 0) {
+ if (!task.Result.HasChildren) {
  // No scores left to retrieve.
  SetTopScores();
  return;
@@ -630,19 +637,20 @@ private void GetInitialTopScores(long batchEnd) {
 
  // Until we have found ScoresToRetrieve unique user scores or run out of
  // scores to retrieve, get another page of score records by ending the next batch
- // (ordered by score) at the lowest score found so far.
- var lastScore = task.Result.Children.First().Child("score").GetRawJsonValue();
- long score, nextEndAt;
+ // (ordered by score) at the worst score found so far.
+ long nextEndAt;
  if (LowestFirst) {
- nextEndAt = Int64.TryParse(lastScore, out score) ?
- score + 1 :
- Math.Min(Int64.MaxValue, batchEnd + 1);
+ nextEndAt = scores.First().Score + 1L;
  } else {
- nextEndAt = Int64.TryParse(lastScore, out score) ?
- score - 1 :
- Math.Max(Int64.MinValue, batchEnd - 1);
+ nextEndAt = scores.Last().Score - 1L;
+ }
+ try {
+ GetInitialTopScores(nextEndAt);
+ } catch (Exception ex) {
+ Debug.LogException(ex);
+ } finally {
+ SetTopScores();
  }
- GetInitialTopScores(nextEndAt);
  });
  }
 
@@ -653,15 +661,16 @@ private void GetInitialTopScores(long batchEnd) {
  /// <param name="snapshot">DataSnapshot record of user scores.</param>
  /// <param name="startTS">Earliest valid timestamp of a user score to retrieve.</param>
  /// <param name="endTS">Latest valid timestamp of a user score to retrieve.</param>
- /// <returns>IEnumerable of valid UserScore objects.</returns>
- private IEnumerable<UserScore> ParseValidUserScoreRecords(
+ /// <returns>List of valid UserScore objects.</returns>
+ private List<UserScore> ParseValidUserScoreRecords(
  DataSnapshot snapshot,
  long startTS,
  long endTS) {
  return snapshot.Children
- .Select(scoreRecord => new UserScore(scoreRecord))
- .Where(score => score.Timestamp > startTS && score.Timestamp <= endTS)
- .Reverse();
+ .Select(scoreRecord => UserScore.CreateScoreFromRecord(scoreRecord))
+ .Where(score => score != null && score.Timestamp > startTS && score.Timestamp <= endTS)
+ .Reverse()
+ .ToList();
  }
 
  /// <summary>

Firebase_Leaderboard/Scripts/UserScore.cs

@@ -17,6 +17,7 @@ limitations under the License.
 using System;
 using System.Collections.Generic;
 using Firebase.Database;
+using UnityEngine;
 
 namespace Firebase.Leaderboard {
  /// <summary>
@@ -52,6 +53,24 @@ public string ShortDateString {
  }
  }
 
+ /// <summary>
+ /// If record contains required score fields, create a new UserScore from it.
+ /// If not, return null.
+ /// </summary>
+ /// <param name="record">The score record object from Firebase Database.</param>
+ public static UserScore CreateScoreFromRecord(DataSnapshot record) {
+ if (record == null) {
+ Debug.LogWarning("Null DataSnapshot record in UserScore.CreateScoreFromRecord.");
+ return null;
+ }
+ if (record.Child(UserIDPath).Exists && record.Child(ScorePath).Exists &&
+ record.Child(TimestampPath).Exists) {
+ return new UserScore(record);
+ }
+ Debug.LogWarning("Invalid record format in UserScore.CreateScoreFromRecord.");
+ return null;
+ }
+
  /// <summary>
  /// Construct a UserScore manually from a User ID, score value, and timestamp.
  /// </summary>
@@ -91,7 +110,7 @@ public UserScore(
  /// Reconstruct a UserScore from a DataSnapshot record retrieved from Firebase Database.
  /// </summary>
  /// <param name="record">The score record object from Firebase Database.</param>
- public UserScore(DataSnapshot record) {
+ private UserScore(DataSnapshot record) {
  UserID = record.Child(UserIDPath).Value.ToString();
  if (record.Child(UsernamePath).Exists) {
  Username = record.Child(UsernamePath).Value.ToString();