Setup devstack-early log

The whole devstack log is written into the console output
(job-output.txt) and into devstacklog.txt.

Remove it from job-output and add a devstack-early log file (same as in
legacy job) that includes all the output of stack.sh.

Make sure the log file is pulled into the stage folder so that it will
end up on logs.o.o.

Change-Id: Ia7c1d8fe5cc03d15f455c6e62ebf4a5f6d62ab1f

playbooks/post.yaml

@@ -3,6 +3,7 @@
   vars:
     devstack_log_dir: "{{ devstack_base_dir|default('/opt/stack') }}/logs/"
     devstack_conf_dir: "{{ devstack_base_dir|default('/opt/stack') }}/devstack/"
+    devstack_full_log: "{{ devstack_early_log|default('/opt/stack/logs/devstack-early.txt') }}"
   tasks:
     # NOTE(andreaf) If the tempest service is enabled, a tempest.log is
     # generated as part of lib/tempest, as a result of verify_tempest_config
@@ -26,6 +27,7 @@
           '{{ devstack_log_dir }}/dstat-csv.log': 'logs',
           '{{ devstack_log_dir }}/devstacklog.txt': 'logs',
           '{{ devstack_log_dir }}/devstacklog.txt.summary': 'logs',
+          '{{ devstack_full_log}}': 'logs',
           '{{ stage_dir }}/verify_tempest_conf.log': 'logs' }
       extensions_to_txt:
         - conf

roles/run-devstack/README.rst

@@ -6,3 +6,9 @@ Run devstack
    :default: /opt/stack
 
    The devstack base directory.
+
+.. zuul:rolevar:: devstack_early_log
+   :default: /opt/stack/log/devstack-early.txt
+
+   The full devstack log that includes the whatever stack.sh logs before
+   the LOGFILE variable in local.conf is honoured.

roles/run-devstack/defaults/main.yaml

@@ -1 +1,2 @@
 devstack_base_dir: /opt/stack
+devstack_early_log: /opt/stack/logs/devstack-early.txt

roles/run-devstack/tasks/main.yaml

@@ -1,5 +1,5 @@
 - name: Run devstack
-  command: ./stack.sh
+  shell: ./stack.sh 2>&1 {{ devstack_early_log }}
   args:
     chdir: "{{devstack_base_dir}}/devstack"
   become: true