Arrow annotation, line not plotting

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1

Bokeh 1.3.4

I am trying to use the Arrow annotation to plot rotating wind direction vectors.
As a simple mock-up to make things work, I am doing:

p = figure(
    title="Wind Direction",
    name="winddir_fig",
    x_axis_type='datetime'
)

p.y_range=Range1d(0, 6)

cds.data['d2'] = cds.data['Date'] + pd.Timedelta(1,unit='hours')

arrows = Arrow(
    end=OpenHead(size=15, line_color='black', line_width=2),
    line_color="black", line_width=2,
    x_start='Date', y_start=2, x_end='d2', y_end=4, 
    source=cds
)

p.add_layout(arrows)

My ColumnDataSource (cds) is made from a Datetime-indexed Pandas dataframe, containing wind direction values, however in this mock-up I am just using the Datetime index to try and make the arrows work.

I added d2 to the cds, which is a copy of the Datetime index (Date) shifted forward one hour. I am trying to plot arrows that span 1-hr on the x-axis, and from 2 to 4 on the y-axis.

I get the following:

bokeh_plot
bokeh_plot1734×300 6.23 KB

The arrows are plotting, but no line.
I also get:
W-1000 (MISSING_RENDERERS): Plot has no renderers: Figure(id='2228', ...)

Not sure what I am doing wrong?

As a follow-up question, I have traditionally used the ray glyph to plot wind direction vectors, using the angle attribute to rotate the lines. Because I cannot put arrows on the ray glyph, I am now trying Arrow. Is there any way to rotate the Arrow annotation using a rotation angle, instead of having to define start and end for both x and y?