Consolidate IP address configuration

[hongbin]

There are several IP address / hostname related configs (i.e. api.host_ip, docker.docker_remote_api_host, websocket_proxy.wsproxy_host) that required manual configuration by operators. Normally, these configs are default as local IP / hostname. It is undesirable for operators to tune all these configs repeatedly. Let's consolidate all these configurations into two defaults:

* [DEFAULT] my_ip: The IP address which the host is using to connect to the management network.
* [DEFAULT] host: Hostname, FQDN or IP address of this host.

Then, use $my_ip as default for all configs that requires an IP address, and use $host as default for all configs that requires a hostname. For example:

    cfg.StrOpt("docker_remote_api_host",
        default="$my_ip",
        ...

Appendix
========
Below is the list of related configs:

[DEFAULT]
# Name of this node. This can be an opaque identifier. It is not necessarily a
# hostname, FQDN, or IP address. However, the node name must be valid within an
# AMQP key, and if using ZeroMQ, a valid hostname, FQDN, or IP address.
# (unknown value)
#host = localhost

[api]
# The listen IP for the zun API server. (IP address value)
#host_ip = 127.0.0.1

[docker]
# API endpoint of docker daemon (string value)
#api_url = unix:///var/run/docker.sock

# Remote API endpoint of docker daemon (string value)
#docker_remote_api_url = tcp://$docker_remote_api_host:$docker_remote_api_port

# Defines the remote api host for the docker daemon. (string value)
#docker_remote_api_host = localhost

[etcd]
# Host IP address on which etcd service running. (unknown value)
#etcd_host = 127.0.0.1

[websocket_proxy]
#
# The URL an end user would use to connect to the ``zun-wsproxy`` service.
#
# The ``zun-wsproxy`` service is called with this token enriched URL
# and establishes the connection to the proper instance.
#
# Related options:
#
# * The IP address must be the same as the address to which the
# ``zun-wsproxy`` service is listening (see option ``wsproxy_host``
# in this section).
# * The port must be the same as ``wsproxy_port``in this section.
# (uri value)
#base_url = ws://$wsproxy_host:$wsproxy_port/

#
# The IP address which is used by the ``zun-wsproxy`` service to listen
# for incoming requests.
#
# The ``zun-wsproxy`` service listens on this IP address for incoming
# connection requests.
#
# Related options:
#
# * Ensure that this is the same IP address which is defined in the option
# ``base_url`` of this section or use ``0.0.0.0`` to listen on all addresses.
# (string value)
#wsproxy_host = 127.0.0.1

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/512183

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/512183
Committed: https://git.openstack.org/cgit/openstack/zun/commit/?id=b64fdd331e08c13550bb44a44cf70cecb65db52a
Submitter: Zuul
Branch: master

commit b64fdd331e08c13550bb44a44cf70cecb65db52a
Author: Kien Nguyen <email address hidden>
Date: Mon Oct 16 13:31:00 2017 +0700

    Consolidate IP address configuration

    There are several IP address / hostname related configs (i.e. api.host_ip,
    docker.docker_remote_api_host, websocket_proxy.wsproxy_host) that required
    manual configuration by operators. Normally, these configs are default as
    local IP / hostname. It is undesirable for operators to tune all these configs
    repeatedly. Let's consolidate all these configurations into two defaults:

    * [DEFAULT] my_ip: The IP address which the host is using to connect to the
    * management network.
    * [DEFAULT] host: Hostname, FQDN or IP address of this host.

    Change-Id: Ie26578c4208a79e4306b1006c6b316a41c2b3540
    Closes-Bug: #1723515

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/zun 1.0.0 release.