We recently added documentation disambiguating the terminology of the
allocation/task working directories. This changeset adds an internals document
that describes in more detail exactly what does into the allocation working
directory, how this interacts with the filesystem isolation provided by task
drivers, and how this interacts with features like `artifact` and `template`.
Co-authored-by: Charlie Voiselle <464492+angrycub@users.noreply.github.com>
Beforehand tasks and field replacements did not have access to the
unique ID of their job or its parent. This adds this information as
new environment variables.
The terms task directory and allocation directory are used throughout the
documentation but these directories are not the same as the `NOMAD_TASK_DIR`
and `NOMAD_ALLOC_DIR` locations. This is confusing when trying to use the
`template` and `artifact` stanzas, especially when trying to use a destination
outside the Nomad-mounted directories for Docker and similar drivers.
This changeset introduces "allocation working directory" to mean the location
on disk where the various directories and artifacts are staged, and "task
working directory" for the task. Clarify how specific task drivers interact
with the task working directory.