This adds a module called common.format_inspector which contains
an implementation of virtual disk format and size detection that
works in a streamable fashion. This can be injected into a data
processing loop and gracefully detect both format type as well as
virtual_size of the disk format, for those that are supported.
Currently excluded from the list of formats that glance claims to
support are iso (which can be treated like raw) and ploop (which
not even qemu-img seems to support).
This also adds a test_format_inspector.py executable into tools/,
which we can use to validate the code manually on images in the
case where bugs report that this fails to work on some real-world
image.
Related to blueprint calculate-virtual-size
Change-Id: Ica9fc645229b0b19b913ce3f2e151f7b0c935649
Without libpq-dev installed you get the following error message with
psycopg2-2.8.1
Error: You need to install postgresql-server-dev-X.Y for building a
server-side extension or libpq-dev for building a client-side application.
see I5e0f6246d010e09065815e9fca5ad2c4da5060b6 for another example
Change-Id: I01735aa3bffbce8e6e182887d8df450fa509c636
This avoids falling back to the global bindep-fallback.txt which
installs a pretty big environment. Without this change, a lot
of additional but unnecessary packages are installed on the nodepool
workers.
Change-Id: Id6c17f9a53ad8ad5f0bb9d308ccf5d33a6f59f7f