ENH: colorful graphs about streamz HOT 6 OPEN

from streamz.

Do we just stuff color information in the graphviz nodes somewhere and expect graphviz to know what to do?

from streamz.

from streamz.

from streamz.

sounds good. tried it and seems simple (use style=filled with color=clr). Looks like we can use much more, such as shape.

Did you have any coloring in mind?
I think differentiating stream methods (map, filter etc) as well as stream subclasses (for example from Stream to DaskStream) could be nice. Maybe it could be something simple such as color for the methods and shape for the subclasses. Since 'method' might be a little ambiguous, here's an example:

from streamz import Stream
s = Stream()
s2 = s.map(lambda x :x + 1)
from streamz import DaskStream
# now objects are Futures
s3 = DaskStream.scatter(s2)
# still a Future
s4 = s3.map(lambda x : x**2)
s5 = DaskStream.gather(s4)

Here s2 and s4 nodes would have the same color but different shape.

Shape would be extremely useful. For example, running filter on a DaskStream would yield a Stream (which is unlikely to be intended use). This could be useful for debugging, where one could use the visualized stream to more quickly see if the data is transforming the way we expect.

What do you think?

from streamz.

I am good with all of those. I'd like to make these (private) attributes of the classes, this way classes which inherent from them/override them would be easy to use. (eg we'd just need to change the shape once for dask streams if they all inherited)
I don't have any particular coloring in mind, we may consider drawing from an MPL color cycle since those are more likely to be colorblind safe.

from streamz.