CSHARP-2043: Added SuppressEnsureIndexes option to GridFSBucketOptions. By default is false and has no impact on any part of the system. If set to true, then suppresses the call to EnsureIndexes which occurs during every GridFS upload call. Benefit of this suppression is that: 1) EnsureIndexes [effectively] does a count against the fs.files collection, which will a) add latency in a cluster with global shards, b) requires find permission which may not be deisrable in a write-only repository and most importantly c) cause entire cluster to become unavailable if any single shard is unavailable, even if data being saved is not housed in the unavailable shard. 2) Less importantly, EnsureIndexes includes a list index command which implies a higher privilege than is really needed. If developer is a) confident that GridFS subsystem is properly set up and b) wants to robustify sharded GridFS against one shard being down c) wants keep client permissions to a minimum

Author: John Gibbons

src/MongoDB.Driver.GridFS/GridFSBucket.cs

@@ -814,16 +814,19 @@ private void EnsureIndexes(IReadWriteBindingHandle binding, CancellationToken ca
             {
                 if (!_ensureIndexesDone)
                 {
-                    var isFilesCollectionEmpty = IsFilesCollectionEmpty(binding, cancellationToken);
-                    if (isFilesCollectionEmpty)
+                    if (!_options.SuppressEnsureIndexes)
                     {
-                        if (!FilesCollectionIndexesExist(binding, cancellationToken))
+                        var isFilesCollectionEmpty = IsFilesCollectionEmpty(binding, cancellationToken);
+                        if (isFilesCollectionEmpty)
                         {
-                            CreateFilesCollectionIndexes(binding, cancellationToken);
-                        }
-                        if (!ChunksCollectionIndexesExist(binding, cancellationToken))
-                        {
-                            CreateChunksCollectionIndexes(binding, cancellationToken);
+                            if (!FilesCollectionIndexesExist(binding, cancellationToken))
+                            {
+                                CreateFilesCollectionIndexes(binding, cancellationToken);
+                            }
+                            if (!ChunksCollectionIndexesExist(binding, cancellationToken))
+                            {
+                                CreateChunksCollectionIndexes(binding, cancellationToken);
+                            }
                         }
                     }
 
@@ -843,16 +846,19 @@ private async Task EnsureIndexesAsync(IReadWriteBindingHandle binding, Cancellat
             {
                 if (!_ensureIndexesDone)
                 {
-                    var isFilesCollectionEmpty = await IsFilesCollectionEmptyAsync(binding, cancellationToken).ConfigureAwait(false);
-                    if (isFilesCollectionEmpty)
+                    if (!_options.SuppressEnsureIndexes)
                     {
-                        if (!(await FilesCollectionIndexesExistAsync(binding, cancellationToken).ConfigureAwait(false)))
-                        {
-                            await CreateFilesCollectionIndexesAsync(binding, cancellationToken).ConfigureAwait(false);
-                        }
-                        if (!(await ChunksCollectionIndexesExistAsync(binding, cancellationToken).ConfigureAwait(false)))
+                        var isFilesCollectionEmpty = await IsFilesCollectionEmptyAsync(binding, cancellationToken).ConfigureAwait(false);
+                        if (isFilesCollectionEmpty)
                         {
-                            await CreateChunksCollectionIndexesAsync(binding, cancellationToken).ConfigureAwait(false);
+                            if (!(await FilesCollectionIndexesExistAsync(binding, cancellationToken).ConfigureAwait(false)))
+                            {
+                                await CreateFilesCollectionIndexesAsync(binding, cancellationToken).ConfigureAwait(false);
+                            }
+                            if (!(await ChunksCollectionIndexesExistAsync(binding, cancellationToken).ConfigureAwait(false)))
+                            {
+                                await CreateChunksCollectionIndexesAsync(binding, cancellationToken).ConfigureAwait(false);
+                            }
                         }
                     }
 

src/MongoDB.Driver.GridFS/GridFSBucketOptions.cs

@@ -29,6 +29,7 @@ public class GridFSBucketOptions
         private ReadConcern _readConcern;
         private ReadPreference _readPreference;
         private WriteConcern _writeConcern;
+        private bool _suppressEnsureIndexes;
 
         // constructors
         /// <summary>
@@ -51,6 +52,7 @@ public GridFSBucketOptions(GridFSBucketOptions other)
             _readConcern = other.ReadConcern;
             _readPreference = other.ReadPreference;
             _writeConcern = other.WriteConcern;
+            _suppressEnsureIndexes = other.SuppressEnsureIndexes;
         }
 
         /// <summary>
@@ -65,6 +67,7 @@ public GridFSBucketOptions(ImmutableGridFSBucketOptions other)
             _readConcern = other.ReadConcern;
             _readPreference = other.ReadPreference;
             _writeConcern = other.WriteConcern;
+            _suppressEnsureIndexes = other.SuppressEnsureIndexes;
         }
 
         // properties
@@ -135,6 +138,18 @@ public WriteConcern WriteConcern
             get { return _writeConcern; }
             set { _writeConcern = value; }
         }
+
+        /// <summary>
+        /// Gets or sets the suppress ensure indexes setting
+        /// </summary>
+        /// <value>
+        /// The suppress ensure indexes setting
+        /// </value>
+        public bool SuppressEnsureIndexes
+        {
+            get { return _suppressEnsureIndexes; }
+            set { _suppressEnsureIndexes = value; }
+        }
     }
 
     /// <summary>
@@ -165,6 +180,7 @@ public static ImmutableGridFSBucketOptions Defaults
         private readonly ReadConcern _readConcern;
         private readonly ReadPreference _readPreference;
         private readonly WriteConcern _writeConcern;
+        private readonly bool _suppressEnsureIndexes;
 
         // constructors
         /// <summary>
@@ -174,6 +190,7 @@ public ImmutableGridFSBucketOptions()
         {
             _bucketName = "fs";
             _chunkSizeBytes = 255 * 1024;
+            _suppressEnsureIndexes = false;
         }
 
         /// <summary>
@@ -188,6 +205,7 @@ public ImmutableGridFSBucketOptions(GridFSBucketOptions other)
             _readConcern = other.ReadConcern;
             _readPreference = other.ReadPreference;
             _writeConcern = other.WriteConcern;
+            _suppressEnsureIndexes = other.SuppressEnsureIndexes;
         }
 
         // properties
@@ -256,5 +274,16 @@ public WriteConcern WriteConcern
         {
             get { return _writeConcern; }
         }
+
+        /// <summary>
+        /// Gets the suppress ensure indexes setting
+        /// </summary>
+        /// <value>
+        /// The suppress ensure indexes setting
+        /// </value>
+        public bool SuppressEnsureIndexes
+        {
+            get { return _suppressEnsureIndexes; }
+        }
     }
 }

tests/MongoDB.Driver.GridFS.Tests/GridFSBucketOptionsTests.cs

@@ -117,7 +117,7 @@ public void constructor_with_immutable_other_should_initialize_instance()
         [Fact]
         public void constructor_with_mutable_other_should_initialize_instance()
         {
-            var other = new GridFSBucketOptions { BucketName = "bucket", ChunkSizeBytes = 123, ReadConcern = ReadConcern.Majority, ReadPreference = ReadPreference.Secondary, WriteConcern = WriteConcern.WMajority };
+            var other = new GridFSBucketOptions { BucketName = "bucket", ChunkSizeBytes = 123, ReadConcern = ReadConcern.Majority, ReadPreference = ReadPreference.Secondary, WriteConcern = WriteConcern.WMajority, SuppressEnsureIndexes = true };
 
             var result = new GridFSBucketOptions(other);
 
@@ -126,6 +126,7 @@ public void constructor_with_mutable_other_should_initialize_instance()
             result.ReadConcern.Should().Be(other.ReadConcern);
             result.ReadPreference.Should().Be(other.ReadPreference);
             result.WriteConcern.Should().Be(other.WriteConcern);
+            result.SuppressEnsureIndexes.Should().Be(other.SuppressEnsureIndexes);
         }
 
         [Fact]
@@ -137,6 +138,7 @@ public void constructor_with_no_arguments_should_initialize_instance_with_defaul
             result.ChunkSizeBytes.Should().Be(255 * 1024);
             result.ReadPreference.Should().BeNull();
             result.WriteConcern.Should().BeNull();
+            result.SuppressEnsureIndexes.Should().BeFalse();
         }
 
         [Fact]
@@ -198,6 +200,26 @@ public void WriteConcern_set_should_have_expected_result()
 
             subject.WriteConcern.Should().Be(WriteConcern.WMajority);
         }
+
+        [Fact]
+        public void SuppressEnsureIndexes_get_should_return_expected_result()
+        {
+            var subject = new GridFSBucketOptions { SuppressEnsureIndexes = true };
+
+            var result = subject.SuppressEnsureIndexes;
+
+            result.Should().BeTrue();
+        }
+
+        [Fact]
+        public void SuppressEnsureIndexes_set_should_have_expected_result()
+        {
+            var subject = new GridFSBucketOptions();
+
+            subject.SuppressEnsureIndexes = true;
+
+            subject.SuppressEnsureIndexes.Should().BeTrue();
+        }
     }
 
     public class ImmutableGridFSBucketOptionsTests
@@ -225,7 +247,7 @@ public void ChunkSizeBytes_get_should_return_expected_result()
         [Fact]
         public void constructor_with_arguments_should_initialize_instance()
         {
-            var mutable = new GridFSBucketOptions { BucketName = "bucket", ChunkSizeBytes = 123, ReadConcern = ReadConcern.Majority, ReadPreference = ReadPreference.Secondary, WriteConcern = WriteConcern.WMajority };
+            var mutable = new GridFSBucketOptions { BucketName = "bucket", ChunkSizeBytes = 123, ReadConcern = ReadConcern.Majority, ReadPreference = ReadPreference.Secondary, WriteConcern = WriteConcern.WMajority, SuppressEnsureIndexes = true };
 
             var result = new ImmutableGridFSBucketOptions(mutable);
 
@@ -234,6 +256,7 @@ public void constructor_with_arguments_should_initialize_instance()
             result.ReadConcern.Should().Be(ReadConcern.Majority);
             result.ReadPreference.Should().Be(ReadPreference.Secondary);
             result.WriteConcern.Should().Be(WriteConcern.WMajority);
+            result.SuppressEnsureIndexes.Should().BeTrue();
         }
 
         [Fact]
@@ -246,6 +269,7 @@ public void constructor_with_no_arguments_should_initialize_instance_with_defaul
             result.ReadConcern.Should().BeNull();
             result.ReadPreference.Should().BeNull();
             result.WriteConcern.Should().BeNull();
+            result.SuppressEnsureIndexes.Should().BeFalse();
         }
 
         [Fact]
@@ -267,6 +291,7 @@ public void Defaults_get_should_return_expected_result()
             result.ReadConcern.Should().BeNull();
             result.ReadPreference.Should().BeNull();
             result.WriteConcern.Should().BeNull();
+            result.SuppressEnsureIndexes.Should().BeFalse();
         }
 
         [Fact]
@@ -298,5 +323,15 @@ public void WriteConcern_get_should_return_expected_result()
 
             result.Should().Be(WriteConcern.WMajority);
         }
+
+        [Fact]
+        public void SuppressEnsureIndexes_get_should_return_expected_result()
+        {
+            var subject = new ImmutableGridFSBucketOptions(new GridFSBucketOptions { SuppressEnsureIndexes = true });
+
+            var result = subject.SuppressEnsureIndexes;
+
+            result.Should().BeTrue();
+        }
     }
 }