bionic (7) PLAINBOX_SESSION_SHARE.7.gz

Provided by: plainbox_0.25-1_all bug

NAME
       PLAINBOX_SESSION_SHARE - per-session runtime shared-state directory


SYNOPSIS
       Saving files to session share directory:

          ``command: do-something > $PLAINBOX_SESSION_SHARE/some-action.log``

       Loading files from session-share directory:

          ``command: cat $PLAINBOX_SESSION_SHARE/some-action.log``


DESCRIPTION
       Plainbox  sessions  allow  jobs  to  communicate  by referring to the $PLAINBOX_SESSION_SHARE environment
       variable. Files generated  therein  are  explicitly  meant  to  be  accessible  to  all  the  other  jobs
       participating in the session.

   Typical Use Cases
       Typically a session will involve one or more pairs of jobs such as:

          id: some-action
          plugin: shell
          summary: do something and save the log file to disk
          commmand: do-something > $PLAINBOX_SESSION_SHARE/some-action.log

          id: some-action-attachment
          plugin: attachment
          summary: log file of the do-something command
          command: cat $PLAINBOX_SESSION_SHARE/some-action.log

       The  job  some-action  will  use  the do-something executable to perform some tests. The log file of that
       action will be saved on the device executing the test, in the directory exposed through  the  environment
       variable $PLAINBOX_SESSION_SHARE.

       The  some-action-attachment job will use that same directory and the agreed-upon name of the log file and
       cat (1) it, which coupled with the plugin type shell will cause Plainbox to attach the log  file  to  the
       resulting document.

   Checkbox Compatibility
       Jobs  designed  to  work with pre-Plainbox-based Checkbox may still refer to the old, somewhat confusing,
       environment variable $CHECKBOX_DATA. It points to the same directory.

   Multi-Node Sessions
       When a test session involves multiple devices this directory is separately instantiated for each  device.
       Jobs  executing on separate devices cannot use this facility to communicate. If communication is required
       jobs  are  expected  to  use  the  LAVA-inspired,  MPI-based   communication   API.   For   details   see
       plainbox-multi-node-api (7)


BUGS
       Within  the session directory the name of this directory is still CHECKBOX_DATA (literally, this is not a
       variable name). It may be changed at any point in time since jobs cannot form  any  meaningful  paths  to
       this directory without referring to either $PLAINBOX_SESSION_SHARE or $CHECKBOX_DATA


SEE ALSO
       PLAINBOX_PROVIDER_DATA, CHECKBOX_DATA


AUTHOR
       Zygmunt Krynicki & Checkbox Contributors


       2012-2014 Canonical Ltd