RUBY-2241 Have driver raise MaxBSONSizeError when document exceeds MaxBsonObjectSize (#2033)

Author: Emily Giurleo

Diff for: lib/mongo/protocol/msg.rb

@@ -147,6 +147,8 @@ def payload
       #
       # @since 2.5.0
       def serialize(buffer = BSON::ByteBuffer.new, max_bson_size = nil)
+        validate_document_size!(max_bson_size)
+
         super
         add_check_sum(buffer)
         buffer
@@ -275,6 +277,23 @@ def bulk_write?
 
       private
 
+      # Validate that the documents in this message are all smaller than the
+      # maxBsonObjectSize. If not, raise an exception.
+      def validate_document_size!(max_bson_size)
+        max_bson_size ||= Mongo::Server::ConnectionBase::DEFAULT_MAX_BSON_OBJECT_SIZE
+
+        contains_too_large_document = @sections.any? do |section|
+          section[:type] == 1 &&
+            section[:payload][:sequence].any? do |document|
+              document.to_bson.length > max_bson_size
+            end
+        end
+
+        if contains_too_large_document
+          raise Error::MaxBSONSize.new('The document exceeds maximum allowed BSON object size after serialization')
+        end
+      end
+
       def command
         @command ||= if @main_document
           @main_document.dup.tap do |cmd|

Diff for: spec/integration/client_side_encryption/auto_encryption_bulk_writes_spec.rb

@@ -113,7 +113,7 @@
         it 'raises an exception' do
           expect do
             bulk_write.execute
-          end.to raise_error(Mongo::Error::MaxBSONSize, /maximum allowed size: 16777216 bytes/)
+          end.to raise_error(Mongo::Error::MaxBSONSize, /The document exceeds maximum allowed BSON object size after serialization/)
         end
       end
     end
@@ -255,7 +255,7 @@
         it 'raises an exception' do
           expect do
             bulk_write.execute
-          end.to raise_error(Mongo::Error::MaxBSONSize, /maximum allowed size: 16777216 bytes/)
+          end.to raise_error(Mongo::Error::MaxBSONSize, /The document exceeds maximum allowed BSON object size after serialization/)
         end
       end
     end
@@ -346,7 +346,7 @@
       it 'raises an exception' do
         expect do
           perform_bulk_write
-        end.to raise_error(Mongo::Error::MaxBSONSize, /maximum allowed size: 16777216 bytes/)
+        end.to raise_error(Mongo::Error::MaxBSONSize, /The document exceeds maximum allowed BSON object size after serialization/)
       end
     end
   end

Diff for: spec/integration/size_limit_spec.rb

@@ -62,13 +62,30 @@
     authorized_collection.insert_one(document)
   end
 
-  it 'fails on the server when a document larger than 16MiB is inserted' do
-    document = { key: 'a' * (max_document_size - 27), _id: 'foo' }
-    expect(document.to_bson.length).to eq(max_document_size+1)
+  context 'on server versions >= 3.6' do
+    min_server_fcv '3.6'
 
-    lambda do
-      authorized_collection.insert_one(document)
-    end.should raise_error(Mongo::Error::OperationFailure, /object to insert too large/)
+    it 'fails on the driver when a document larger than 16MiB is inserted' do
+      document = { key: 'a' * (max_document_size - 27), _id: 'foo' }
+      expect(document.to_bson.length).to eq(max_document_size+1)
+
+      lambda do
+        authorized_collection.insert_one(document)
+      end.should raise_error(Mongo::Error::MaxBSONSize, /The document exceeds maximum allowed BSON object size after serialization/)
+    end
+  end
+
+  context 'on server versions <= 3.4' do
+    max_server_fcv '3.4'
+
+    it 'fails on the server when a document larger than 16MiB is inserted' do
+      document = { key: 'a' * (max_document_size - 27), _id: 'foo' }
+      expect(document.to_bson.length).to eq(max_document_size+1)
+
+      lambda do
+        authorized_collection.insert_one(document)
+      end.should raise_error(Mongo::Error::OperationFailure, /object to insert too large/)
+    end
   end
 
   it 'fails in the driver when a document larger than 16MiB+16KiB is inserted' do