How to make sure the whole node (circle + text) follows the constraint of non-overlapping?

[uraniumreza]

I'm trying to visualize a pretty basic DAG layout using d3Cola - constraints and flowLayout. The node labels are long e.g. ~40 characters. How can I make sure that these labels won't overlap with each other also maintains the given constraint?

[yusufades]

resize the nodes so their width matches the width of the text.