allow 'extraHosts' to accept hostname as destination ip

[jgangemi]

this is similar to #101.

i want to specify a hostname as the destination address in the maven configuration that will be resolved to an ip address at runtime, eg:

<run>
  <extraHosts>
    <host>dev-db.hostname.pvt:docker-dev.hostname.pvt</host>
  </extraHosts>
</run>

this lets me inject the correct ip address by way of /etc/hosts instead of using maven properties.

if the specified host cannot be resolved at start time, the plugin will throw an error.

[rhuss]

If I understand right, you want in you example docker-dev.hostname.url to be looked up by the plugin before handing it over to Docker as extraHosts.

Looks good to me.

[rakeshbalan]

@rhuss I am using the hostname of a running container instead of its IP. But I am getting the following error
unable to resolve ip address for <container-hostname>: Unknown host <container-hostname>: Name or service not known

Am I missing anything!!!

                             <image>
                                <name>docker.io/rabbitmq:${docker.rabbitmq.version}</name>
                                <alias>rabbitmq-az1</alias>
                                <run>
                                    <namingStrategy>alias</namingStrategy>
                                    <hostname>rabbitmq-az1</hostname>
                                    <ports>
                                        <port>15673:15672</port>
                                    </ports>
                                    <wait>
                                        <time>30000</time>
                                        <log>Server startup complete*</log>
                                        <exec>
                                            <postStart>rabbitmq-plugins enable rabbitmq_management</postStart>
                                        </exec>
                                    </wait>
                                </run>
                            </image>

                         <image>
                                <name>${docker-organization-name}/pulse-az1:${project.version}</name>
                                <alias>pulse-az1</alias>
                                <run>
                                    <namingStrategy>alias</namingStrategy>
                                    <hostname>pulse-az1</hostname>
                                    <extraHosts>
                                        <extraHost>rabbitmq:rabbitmq-az1</extraHost>
                                    </extraHosts>
                                    <ports>
                                        <port>8081:8080</port>
                                    </ports>
                                    <env>
                                        <SOH_LOGLEVEL>ALL</SOH_LOGLEVEL>
                                    </env>
                                    <links>
                                        <link>rabbitmq-az1</link>
                                    </links>
                                    <wait>
                                        <time>600000</time>
                                        <log>transitioning from STARTING to STARTED</log>
                                    </wait>
                                    <log>
                                        <prefix>PULSE-AZ1</prefix>
                                        <date>default</date>
                                        <color>blue</color>
                                    </log>
                                </run>
                            </image>

EXACT ERROR:
[ERROR] Failed to execute goal io.fabric8:docker-maven-plugin:0.16.9:start (default-cli) on project docker-assemble: Execution default-cli of goal io.fabric8:docker-maven-plugin:0.16.9:start failed: Failed to create contained configuration for [feedzai/stateofohio/pulse-az1:3.1-SNAPSHOT]: unable to resolve ip address for rabbitmq-az1: Unknown host rabbitmq-az1: Name or service not known

[rhuss]

@rlingaku Could you add a <dependsOn> as described here --> https://dmp.fabric8.io/#start-depends-on ?

Does this help ?

[rakeshbalan]

@rhuss I tried with <dependsOn>, but I still get the same error