bad service_port if service_host is not specified in the relation data

[Junien F]

Hi,

If you set the "services" config option to the empty string, and send the following as reverseproxy relation data in "services" :

  - { service_name: foo,
      service_options: [mode http, balance leastconn],
      service_port: 8080
      servers: [[foo bar_0, 10.0.0.1, 8080, 'check port 8080']] }

then haproxy will bind the port 10002 for this service.

The reason is that there is a bug in the ensure_service_host_port() function :

 562 def ensure_service_host_port(services):
 563 config_data = config_get()
 564 seen = []
 565 missing = []
 566 for service, options in sorted(services.iteritems()):
 567 if "service_host" not in options:
 568 missing.append(options)
 569 continue
 570 if "service_port" not in options:
 571 missing.append(options)
 572 continue
 573 seen.append((options["service_host"], int(options["service_port"])))
 574
 575 seen.sort()
 576 last_port = seen and seen[-1][1] or int(config_data["monitoring_port"])
 577 for options in missing:
 578 last_port += 2
 579 options["service_host"] = "0.0.0.0"
 580 options["service_port"] = last_port
 581
 582 return services

Here, we have a single "missing" option (service_host), but as you can see in the last "for" loop, the service_port is overriden even if only service_host is missing.

And since, for unknown reason, last_port is set to the default monitoring_port of 10000, the service_port ends up being 10002.