The GET method fetches the content of a VNF package identified by
the VNF package identifier allocated by the NFVO.
The 'HTTP_RANGE' header is inspected for a valid value.
If it is present and valid, then the package content within
the range is fetched.If not present the entire content is
fetched
A 'size' column has been added to vnf_packages db table.
When the VNF package content is uploaded, the size of the
csar zip is persisted in this newly added 'size' column of
vnf_packages db table.
When VNF_Package content is fetched for the first time, its size is
retrieved from glance store and the size column in vnf packages table
is populated with this value. For subsequent fetch calls the size of
csar file content is retrieved from 'size' column in vnf_packages
table.
A lot of the content fetching code has been reused from
glance/api/v2/image_data.py ResponseSerializer class
download function
Blueprint: bp/enhance-vnf-package-support-part1
Change-Id: Ib49ef8b1e81ca4a4b7e3ac4a0836c111ce7da4a3
d3cc82139e