title: how can i use tap tool with bar chart -bokeh
body: <p>while using bokeh tap tool with bar chart I need to get the id of selected bar.how can I get this id of each bar without using customJS
  the code is running using bokeh server</p>
  
  <pre><code>source = ColumnDataSource(data=df)
  
  p = figure(x_range=source.data['month'], plot_height=600, toolbar_location=None, tools="tap,hover", title="month analysis")
  
  p.vbar(x='month', top='count', width=0.5, source=source, legend="month",
         line_color='white', fill_color=factor_cmap('month', palette=Spectral6, factors=df['month']))
  hover = HoverTool(tooltips=[("count", "@count")])
  
  
  p.legend.orientation = "horizontal"
  p.legend.location = "top_right"
  
  
  taptool = p.select(type=TapTool)
  
  
  curdoc().add_root(row( p, width=800))
  </code></pre>