dnsdist test_dnsdisttcp_cc/test_IncomingConnection* not as protocol neutral as maybe expected

[zeha]

• Program: dnsdist
• Issue type: Bug report/Feature request?

Short description

The tests seem to require a working IPv4 setup, although they seem to mock all (relevant) network connectivity.

Environment

• Operating system: Debian bullseye (testing)
• Software version: 1.6.0
• Software source: source tarball

Longer description

Debian builds dnsdist on (some) IPv6-only buildds. Unfortunately the exact setup is not documented properly.

Build log for 1.6.0: https://buildd.debian.org/status/fetch.php?pkg=dnsdist&arch=amd64&ver=1.6.0-1&stamp=1620902648&raw=0

Relevant test log output:

test-dnsdisttcp_cc.cc(213): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnection_BackendNoOOOR": critical check step.request == !d_client ? ExpectedStep::ExpectedRequest::closeClient : ExpectedStep::ExpectedRequest::closeBackend has failed [connect to the backend != close connection to backend]�[0;39;49m
terminate called after throwing an instance of 'boost::execution_aborted'
unknown location(0): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnection_BackendNoOOOR": signal: SIGABRT (application abort requested)�[0;39;49m
test-dnsdisttcp_cc.cc(213): �[1;36;49mlast checkpoint�[0;39;49m
test-dnsdisttcp_cc.cc(213): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnectionOOOR_BackendOOOR": critical check step.request == !d_client ? ExpectedStep::ExpectedRequest::closeClient : ExpectedStep::ExpectedRequest::closeBackend has failed [connect to the backend != close connection to backend]�[0;39;49m
terminate called recursively
unknown location(0): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnectionOOOR_BackendOOOR": signal: SIGABRT (application abort requested)�[0;39;49m
test-dnsdisttcp_cc.cc(213): �[1;36;49mlast checkpoint�[0;39;49m
test-dnsdisttcp_cc.cc(213): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnectionOOOR_BackendNotOOOR": critical check step.request == !d_client ? ExpectedStep::ExpectedRequest::closeClient : ExpectedStep::ExpectedRequest::closeBackend has failed [connect to the backend != close connection to backend]�[0;39;49m
terminate called recursively
unknown location(0): �[4;31;49mfatal error: in "test_dnsdisttcp_cc/test_IncomingConnectionOOOR_BackendNotOOOR": signal: SIGABRT (application abort requested)�[0;39;49m
test-dnsdisttcp_cc.cc(213): �[1;36;49mlast checkpoint�[0;39;49m

This is preceded by lots of these:

Error connecting to new server with address 192.0.2.1:53: connecting socket to 192.0.2.1:53: Network is unreachable

After having a quick look at the test code, it would appear (almost?) all network communication is mocked anyway. What is probably left is the routing lookup for 192.0.2.x, which would fail on a machine with no IPv4 connectivity.

It would be great if these bits could also be mocked away somehow.

Many thanks!

[rgacogne]

The Error connecting to new server with address 192.0.2. lines seem to come from test-dnsdistlbpolicies_cc.cc, perhaps we could get rid of them by setting connect=false in the ctor (untested). I'm not sure yet why the test-dnsdisttcp_cc.cc test fail, though.

[rgacogne]

Right, that fails because connect() is called by TCPIOHandler::tryConnect directly, and the mocked part is only called after that.