After being punched, Laguerre filed a complaint with police who opened an investigation into "sexual harassment" and "violence with a weapon". She gave a string of interviews urging French woman to no longer "keep quiet" about such attacks.
Describing her deal on social media, she wrote in English: "I walked past a man who sexually/verbally harrassed me. "He wasn't the first one and I can't accept being humiliated like that, so I replied 'shut up'," she wrote.
"He then threw an ashtray at me, before rushing back to punch me, in the middle of the street, in front of dozens of people." She later told Le Parisien that he had insulted her repeatedly and made sexually suggestive "groans".
The bar's CCTV caught the incident on camera.
It shows a woman in red walking past the bar before being pursued by a man in black who violently hits her face and walks off. Several bystanders at the terrace then immediately stand up and try and intervene, preventing the man from approaching Laguerre.
He then walks off, and she too walks out of view. Describing his behaviour as "unacceptable", Laguerre wrote: "It happens everyday, everywhere and I don't know a single woman who doesn't have a similar story.
"I am sick of feeling unsafe waking in the street. Things need to change, and they need to change now."
The film of the attack has been viewed 2.3 million times on Facebook.
Laguerre has also launched a website allowing victims of harassment to recount their ordeal online. Nous Toutes Harcelement (We are all harassed) aims to collect accounts of incidents "in the street, at work, in the private sphere".
"It's anonymous, and that will allow these women to talk freely," said Laguerre.
France's new bill against "sexist outrage" passed this month will help act as a "deterrent" against such attacks, said gender equality minister, Marlène Schiappa.
The bill outlaws sexual or sexist comments and degrading, intimidating or hostile behaviour, expands the criminal definition of child rape and extends the statute of limitations for sex crimes.
However, police unions and feminists have criticised it as unworkable.