Type Annotations (Python 3.6)

[Stiivi]

Add type annotations and remove all unnecessary type ambiguity.

This is backward incompatible change and will make Cubes depend on Python ≧3.6. Lower versions of python will not be supported.

Annotate:

• [x] Workspace
• [x] Stores
• [ ] Metadata
  • [x] Dimension
  • [x] Cube
  • [x] Attributes
  • [ ] Providers
  • [ ] Base
• [ ] Query
  • [x] Browser
  • [x] Cell
  • [x] Result
  • [x] Drilldown
  • [ ] Computation
  • [ ] Statutils
• [ ] SQL query builder
  • [x] Browser
  • [ ] Expressions
  • [x] Functions
  • [ ] Logging
  • [x] Mapper
  • [x] Query
  • [x] Store
  • [ ] Utils
• [x] Mapper
• [x] Errors
• [x] Logging
• [x] Calendar
• [x] Datastructures
• [x] Namespace
• [ ] Formatters
• [ ] Ext
• [ ] Slicer tool
• [ ] Auth
• [ ] Common

Tech debt

The following list is being updated as annotations are added.

• [ ] There is temporary _ValueType, _CalculatorFunction, _RecordType type in statutils.py
• [ ] HierarchyPath needs to be revisited (see also #409)
• [ ] _OrderType and _OrderArgType (see also #395)

[mattyangk]

Good to see that :+1:

[martianboy]

On the client side I had to rewrite the cubes.js lib in typescript just to get static type checking. Good to have it here, too. 👍🏼

[Stiivi]

@martianboy Is that cube.js in typescript open-sourceable?

[martianboy]

@Stiivi Yes. It needs a bit of polishing and removing a few dependencies. Will publish it in a day or two.

[Stiivi]

Collection of non-intuitive types discovered during this process.

[Stiivi]

This change is needed in MyPy Typeshed to progress further with annotations of SQL browser.

More typeshed updates to come for the query builder.

[Stiivi]

Removed server from the list of needed packages as it now lives in it's own repo: https://github.com/DataBrewery/slicer-flask.

See separated issue: DataBrewery/slicer-flask#1