fix filter manager crash (#6)

upstream host needs to be available during filter destructors since filters
might use it for accessing stats, etc.

source/common/network/filter_manager.h

@@ -61,9 +61,9 @@ class FilterManager {
 
  Connection& connection_;
  BufferSource& buffer_source_;
+ Upstream::HostDescriptionPtr host_description_;
  std::list<ActiveReadFilterPtr> upstream_filters_;
  std::list<WriteFilterPtr> downstream_filters_;
- Upstream::HostDescriptionPtr host_description_;
 };
 
 } // Network

test/common/network/filter_manager_test.cc

@@ -6,6 +6,7 @@
 #include "test/mocks/upstream/host.h"
 
 using testing::InSequence;
+using testing::NiceMock;
 using testing::Return;
 
 namespace Network {
@@ -19,20 +20,33 @@ class NetworkFilterManagerTest : public testing::Test, public BufferSource {
  Buffer::OwnedImpl write_buffer_;
 };
 
+class LocalMockFilter : public MockFilter {
+public:
+ LocalMockFilter(const Upstream::HostDescription* host) : host_(host) {}
+ ~LocalMockFilter() {
+ // Make sure the upstream host is still valid in the filter destructor.
+ callbacks_->upstreamHost()->url();
+ }
+
+private:
+ const Upstream::HostDescription* host_;
+};
+
 TEST_F(NetworkFilterManagerTest, All) {
  InSequence s;
- std::shared_ptr<MockReadFilter> read_filter(new MockReadFilter());
- std::shared_ptr<MockWriteFilter> write_filter(new MockWriteFilter());
- std::shared_ptr<MockFilter> filter(new MockFilter());
+
+ Upstream::HostDescription* host_description(new NiceMock<Upstream::MockHostDescription>());
+ MockReadFilter* read_filter(new MockReadFilter());
+ MockWriteFilter* write_filter(new MockWriteFilter());
+ MockFilter* filter(new LocalMockFilter(host_description));
 
  MockConnection connection;
  FilterManager manager(connection, *this);
- manager.addReadFilter(read_filter);
- manager.addWriteFilter(write_filter);
- manager.addFilter(filter);
+ manager.addReadFilter(ReadFilterPtr{read_filter});
+ manager.addWriteFilter(WriteFilterPtr{write_filter});
+ manager.addFilter(FilterPtr{filter});
 
- Upstream::HostDescriptionPtr host_description(new Upstream::MockHostDescription());
- read_filter->callbacks_->upstreamHost(host_description);
+ read_filter->callbacks_->upstreamHost(Upstream::HostDescriptionPtr{host_description});
  EXPECT_EQ(read_filter->callbacks_->upstreamHost(), filter->callbacks_->upstreamHost());
 
  read_buffer_.add("hello");