When the tests are run against an external server in this order:
`--single unit/introspection --single unit/moduleapi/blockonbackground
--single integration/redis-cli`
the test would hang when the "ASK redirect test" test attempts to create
a listening socket (it fails, and then redis-cli itself hangs waiting
for a non-responsive socket created by the introspection test).
the reasons are:
1. the blockedbackground test includes util.tcl and resets the
`::last_port_attempted` variable
2. the test in introspection didn't close the listening server, so it's
still alive.
3. find_available_port doesn't properly detect the busy port, and it
thinks that the port is free even though it's busy.
fixing all 3 of these problems, even though fixing just one would be
enough to let the test pass.
When redis-cli received ASK, it used string matching wrong and didn't
handle it.
When we access a slot which is in migrating state, it maybe
return ASK. After redirect to the new node, we need send ASKING
command before retry the command. In this PR after redis-cli receives
ASK, we send a ASKING command before send the origin command
after reconnecting.
Other changes:
* Make redis-cli -u and -c (unix socket and cluster mode) incompatible
with one another.
* When send command fails, we avoid the 2nd reconnect retry and just
print the error info. Users will decide how to do next.
See #9277.
* Add a test faking two redis nodes in TCL to just send ASK and OK in
redis protocol to test ASK behavior.
Co-authored-by: Viktor Söderqvist <viktor.soderqvist@est.tech>
Co-authored-by: Oran Agra <oran@redislabs.com>
Oran Agra