Regression: Ambassador 0.50.0-ea7 tracing does not work with long cluster names

[flands]

Describe the bug

If you enable tracing with a long cluster name then configuration will fail

To Reproduce

Two ways with different results:

Upgrade from 0.40.1 to 0.50.0-ea7 in a configuration with tracing enabled and long cluster name. Result is Ambassador in a CrashLoopBackoff

Deploy fresh 0.50.0-ea7 and then enabled tracing. Ambassador starts (assuming initially configured without tracing), but once tracing is enabled Ambassador configuration remains unchanged.

Expected behavior

No error, tracing works (given it works in Ambassador 0.40.1)

Versions (please complete the following information):

• Ambassador: 0.50.0-ea7
• Kubernetes environment [e.g. Minikube, bare metal, Google Kubernetes Engine]: bare metals
• Version [e.g. 1.8.1]: 1.11.5

Additional context

[2018-12-08 00:05:23.027][000021][info][config] [source/server/configuration_impl.cc:103]   loading tracing driver: envoy.zipkin
[2018-12-08 00:05:23.028][000021][critical][main] [source/server/server.cc:81] error initializing configuration '/ambassador/bootstrap-ads.json': envoy.zipkin: unknown cluster 'cluster_tracing_jaeger_collector_default_svc_cluster_local_9411'

                    "cluster_name": "cluster_tracing_jaeger_collector_default-0",
                    "endpoints": [
                        {
                            "lb_endpoints": [
                                {
                                    "endpoint": {
                                        "address": {
                                            "socket_address": {
                                                "address": "jaeger-collector.default.svc.cluster.local",
                                                "port_value": 9411,
                                                "protocol": "TCP"
                                            }
                                        }
                                    }
                                }
                            ]
                        }
                    ]
                },
                "name": "cluster_tracing_jaeger_collector_default-0",
                "type": "STRICT_DNS"
            }
        ]
    },
    "tracing": {
        "http": {
            "config": {
                "collector_cluster": "cluster_tracing_jaeger_collector_default_svc_cluster_local_9411"
            },
            "name": "envoy.zipkin"
        }

[flands]

/cc @kflynn

[kflynn]

Fixed in -rc1.