A divided court held the search to be unconstitutional. It is hard to believe that three U.S. Supreme Court judges determined this type of police conduct was constitutional. However, the majority of the U.S. Supreme Court held the prolonged detection after the police gave Mr. Rodriquez his warning was unconstitutional because the police officer lacked reasonable suspicion (to keep messing with him). Once the police gave Mr. Rodriguez the warning, they should have let him drive away.
Unfortunately, the reality is this case will have little practical application. Most police officers will invent some reason to claim the extended delay in conducting a drug dog sniff was based on a made up fact to support reasonable suspicion. They will say they smelled marijuana, the driver was acting suspicious or the area is known for illegal drug activity. This type of explanation will make an illegal search legal, see Rodriquez v. United States. You should video the stop, as long as the video is not interfering with police business. It is lawful to record the police. Insist on the police telling you why you were being detained. Ask if you are free to leave. Comply with the requests of the police, except for consenting to let them search your car.