Deploying MercuryDPM using Ansible

This is useful if you want to automate deployment and running of MDPM on remote environments. In this example, I'll be controlling a remote machine called 'albatross', a Raspberry Pi with username 'pi'. I'll be building a driver and running it doing all the parameterisations through Ansible.

Preparation

Setting up inventory

Create a file called hosts and put in it the IP address of the remote machine:

hosts

[albatross]
192.168.1.108  # the IP address of the remote machine

When you have created a playbook, you have to specify using this hosts file by running ansible-playbook -i hosts playbook.yaml.

Setting up connection credentials

On the remote system, add your SSH public key to ~/.ssh/authorized_keys.

Playbook

In your base directory, create the file playbook.yml:

playbook.yaml

--- 
- name: Mount storage
  hosts: albatross
  remote_user: pi
  become: no
  gather_facts: no

  vars_files:
    - vars.yml

  roles:
    - role: mountstorage


- name: Build and run MercuryDPM
  hosts: albatross
  remote_user: pi
  become: no # FIXME Do we have to run everything as root?
  gather_facts: no

  vars_files:
    - vars.yml

  roles: 
    - role: workhorse

Mounting storage

If you're storing on a local disc, nothing needs to be done here. If you want to store on a Google Drive, an S3 bucket or a remote filer, then you will need to have a role for mountstorage.

Tasks for the `workhorse` role

Create a file at workhorse/tasks/main.yml (relative to your base directory) and put the following in it.:

workhorse/tasks/main.yml

---
# tasks file for workhorse
- name: update apt cache and install common packages
  apt:
    update_cache: yes
    name:
      - python3
  become: yes

- name: Download and build MercuryDPM 
  block:
    - name: Install MercuryDPM dependencies
      apt:
        update_cache: yes
        name:
          - build-essential
          - g++
          - gfortran
          - subversion
          - cmake
          - graphviz
        state: present
      become: yes

    - name: Copy MercuryDPM build script
      copy: src=build_mdpm.sh dest=/opt mode=0755

    - name: Download and build MDPM
      command: bash /opt/build_mdpm.sh
      register: build_output

    - name: Print info
      debug: msg="{{build_output.stdout}}"
    - name: Print errors
      debug: msg="{{build_output.stderr}}"

- name: Prepare script that builds and runs driver
  template:
    src: build_and_run_driver.sh.j2
    dest: /opt/MercuryDPM/build_and_run_driver.sh
    mode: 0755

- name: Run that script
  # TODO https://stackoverflow.com/questions/39347379/ansible-run-command-on-remote-host-in-background
  shell: (nohup /opt/MercuryDPM/build_and_run_driver.sh </dev/null >/dev/null 2>&1 &)
  # command: bash /opt/MercuryDPM/build_and_run_driver.sh
  async: 10
  poll: 0

`workhorse/files/build_mdpm.sh`: Download MercuryDPM and build MercuryBase

This script downloads MercuryDPM and builds MercuryBase.

workhorse/files/build_mdpm.sh

#!/bin/bash
set -eux

DPMDIR=/opt/MercuryDPM

declare -a SVN_FLAGS="--non-interactive --trust-server-cert --trust-server-cert-failures=unknown-ca,cn-mismatch,expired,not-yet-valid,other"
declare -a CMAKE_FLAGS="-DCMAKE_BUILD_TYPE=Release -DMercury_BUILD_DOCUMENTATION=OFF -DMercury_BUILD_USER_DIR=OFF -DMercury_Include_Xballs_Support=OFF -DMercury_USE_MPI=OFF"

mkdir -p $DPMDIR && cd $DPMDIR
# CHANGEME if you want to log in as a user so that you can build the USER/ directory
svn checkout https://svn.MercuryDPM.org/SourceCode/Trunk MercurySource --username guest --password '' ${SVN_FLAGS}
cd $DPMDIR/MercurySource

# CHANGEME If you want to use a particular version of MercuryDPM
# SVN_VERSION=5000
# svn update -r $SVN_VERSION --username guest --password '' ${SVN_FLAGS}

mkdir -p $DPMDIR/MercuryBuild && cd $DPMDIR/MercuryBuild
rm -f CMakeCache.txt

# Call cmake twice so that the CMakeDefinitions files are generated
# properly.
cmake ${CMAKE_FLAGS} ../MercurySource
cmake ${CMAKE_FLAGS} ../MercurySource
make clean
make mercury

`workhorse/templates/build_and_run_driver.sh.j2`: Build and run your driver

workhorse/templates/build_and_run_driver.sh.j2

#!/bin/bash
set -eux
DPMDIR=/opt/MercuryDPM
SIMDIR=/mnt/s3gf/{{series}}/{{simulation}}
DRIVER_DIR=$DPMDIR/MercuryBuild/Drivers/{{driver_dir}}
DRIVER_PATH=$DRIVER_DIR/{{driver}}
cd $DRIVER_DIR
make {{driver}}
mkdir -p $SIMDIR
cd $SIMDIR
$DRIVER_PATH {{flags}}