Murano's application packages can now be stored either in database
(using murano-api) or in Glance Artifact repository (so-called Glance
V3 api). This patch adds an experimental support of the latter
approach to murano engine.
As all the difference between these two storages is incapsulated in
the murano client, engine just needs to configure it properly by
passing an instance of glance v3 client on creation. This is
controlled by a 'packages_service' parameter of 'packages_opts'
configuration group. It is set to 'murano' by default and indicates
the usage of old, database-backed storage. If set to 'glance', the
murano client will encapsulate glance v3 connector and thus the
packages will be accessed from Glance Artifact Repository.
The settings of Glance client are also added to the configuration, as
well as a client factory to generate the client. As these settings may
now conflict with the settings "demo plugin", the appropriate
configuration section is renamed in the latter.
This patch also contains a couple of utility functions to transform
partial semver version specs into non-partial ones and - further - to
a set of Glance query parameters needed to filter the artifacts based
on that spec.
Change-Id: I690467e43b6b63850ebecef756635241e623554c
Implements-blueprint: artifact-repository-support
df95ad397e