Allow additional mesos master and slave configs

[lhoss]

This allows very flexible additional configurations.

Example usage, that we use in prod. both for the master and slave:

  mesos_master_additional_configs:
  - name: MAX_COMPLETED_FRAMEWORKS
    value: 50
  - name: MAX_COMPLETED_TASKS_PER_FRAMEWORK
    value: 30

  mesos_slave_additional_configs:
  - name: RESOURCES
    value: "{{mesos_slave_resources}}"
  - name: HADOOP_HOME
    value: "{{hadoop_home}}"

@ernestas-poskus any chance to get a review and potential merge ?!

[ernestas-poskus]

@lhoss please bump https://github.com/AnsibleShipyard/ansible-mesos/blob/master/vars/main.yml#L2

to v0.4.0

[ernestas-poskus]

@lhoss can you provide links to documentation, are you sure all additional config begins with MESOS_* ?

[ernestas-poskus]

👍 creative

[lhoss]

I bumped the version, but now it conflicts. How should we proceed? ( Should I solve by merging latest master into my branch first ?)

[lhoss]

@lhoss can you provide links to documentation, are you sure all additional config begins with MESOS_* ?

http://mesos.apache.org/documentation/latest/configuration/

By setting the environment variable MESOS_OPTION_NAME (the option name with a MESOS_ prefix added to it)

[ernestas-poskus]

I bumped the version, but now it conflicts. How should we proceed? ( Should I solve by merging latest master into my branch first ?)

@lhoss rebase on master, there were changes of mesos_playbook_version

[ernestas-poskus]

I have checked

http://mesos.apache.org/documentation/latest/configuration/

It says

By setting the environment variable MESOS_OPTION_NAME (the option name with a MESOS_ prefix added to it).

I am not sure whether this is implicitly set by MESOS, in this case it must be defined here explicitly before other expoerts, please define it and make 'MESOS_' as configurable variable.

[lhoss]

@ernestas-poskus rebased 👍

[ernestas-poskus]

@lhoss

http://mesos.apache.org/documentation/latest/configuration/

Please export explicitly MESOS_OPTION_NAME="{{ mesos_option_name }}" in both slave/master templates and in defauflts/main.yml

[lhoss]

@ernestas-poskus ah I forget to ask for clarification about MESOS_OPTION_NAME:
So you want me to make a variable of the string 'MESOS_' (I would call and set it mesos_option_prefix="MESOS_") and then obviously use the variable in the template ?
Despite that in Mesos this is hardcoded and will higly-probably never change.
Also there's no ENV Var called MESOS_OPTION_NAME(it's just a pattern.) To avoid confusion they should have written it like MESOS_<name of mesos option (in uppercase)>

[ernestas-poskus]

@lhoss yes please make
MESOS_ as variable

and export MESOS_OPTION_NAME to that variable

so it would be explicit and obvious for others

[lhoss]

and export MESOS_OPTION_NAME to that variable

ok will do now!
Are you ok with export MESOS_OPTION_PREFIX... (IMHO more precise) ?
( I hope you agree that MESOS_OPTION_NAME is not used by mesos anyway, and would just lead to more confusion ?! )

[lhoss]

@ernestas-poskus For consistency then, we should also replace the 'MESOS_' string in the conf-mesos.j2 template (that I repeat wasn't enhanced in this PR). ok for you?

# Additional configs
{% for config_item in mesos_additional_configs %}
export MESOS_{{config_item.name}}={{config_item.value}}
{% endfor %}

Finally you want me to add the export to all 3 conf-mesos* files ? (Else I'ld only add to the main conf-mesos)

[ernestas-poskus]

Are you ok with export MESOS_OPTION_PREFIX... (IMHO more precise) ?

👍

[ernestas-poskus]

@lhoss

For consistency then, we should also replace the 'MESOS_' string in the conf-mesos.j2 template

export MESOS_QUORUM="{{ mesos_quorum }}"
export MESOS_WORK_DIR="{{ mesos_work_dir }}"
export MESOS_PORT="{{ mesos_master_port }}"

those ☝️ could be referenced in mesos_master_additional_configs and slave, additional_configs respectively.

It's up to you whether you want to do it in this PR or other

[ernestas-poskus]

Good job 👍

[ernestas-poskus]

👍

[lhoss]

It's up to you whether you want to do it in this PR or other

I'ld rather get this merged 👍

[lhoss]

To be sure I exactly understand your proposed change.

taking out the hardcoded lines in the template:

export MESOS_QUORUM="{{ mesos_quorum }}"
export MESOS_WORK_DIR="{{ mesos_work_dir }}"
export MESOS_PORT="{{ mesos_master_port }}"

and add entries to the corresponding list var(s) ?
For ex. in the case of the mesos-master:

mesos_master_additional_configs:
 - name: MESOS_QUORUM
   value: "{{ mesos_quorum }}"

[ernestas-poskus]

To be sure I exactly understand your proposed change.

taking out the hardcoded lines in the template:

export MESOS_QUORUM="{{ mesos_quorum }}"
export MESOS_WORK_DIR="{{ mesos_work_dir }}"
export MESOS_PORT="{{ mesos_master_port }}"
and add entries to the corresponding list var(s) ?
For ex. in the case of the mesos-master:

mesos_master_additional_configs:
 - name: MESOS_QUORUM
   value: "{{ mesos_quorum }}"

exactly

[ernestas-poskus]

thank you for contribution 👍