Refactor to new Upload Service

[fabiosimeoni]

grade installations now expose an Upload Service for xml, csv, and json data.

we no longer need to pass through the API of a VR plugin, which wasn't intended for direct, programmatic publication and makes for awkward idioms.

furthermore, all future evolution to the ingestion logic in grade will pass through the Upload Service and the VR plugin will become outdated.

Refactor to the new Upload Service.

[fabiosimeoni]

first draft of a GradePublisher that offers an embedded DSL based on Java 8 lambdas over standard jax-rs facilities.

Tested with rfb:

drop("rfb.xml").with(xml).in(ami).as("rfb");

we can:

• drop() files or directly InputStreams
• use enumeration for supported data types (xml,json,csv) and known deployments (ami for now, then preproduction and production)

we still do not have a neat solution for csv, which requires additional parsing directives and a multipart request. working next on how to cover that special case along with the others.

[fabiosimeoni]

second draft of GradePublisher with support for csv uploads.

tested with AdminUnitGlue:

Csv csv = csv().delimitedBy(',').in("UTF-16");
drop("admin-units.txt").with(csv).in(ami).as("admin-units");

DSL is stabler now as follows:

drop( InputStream | String ).with(UploadInfo).in(Deployment).as(String);

• as in the previous example, drop(String) loads the stream from the filename in input.
• UploadInfo is a class with two static final constants - xml and json - and one subclass Csv. The latter takes parsing options and serialises to json. Internally, 'UploadInfo' is also responsible for actions specific to the different media types, particularly the body of the requests. For example, the Csv subclass knows that the body has to be multipart and knows how to build it.
• Deployment is an enum with known Grade installations and relative configuration, like ami @ grade.ddns.net.

Finally, xml and json uploads are compressed now.

[fabiosimeoni]

csv uploads also compressed now.