Aggravating features included the fact there was an attack to the head, and that the victim's injuries were "relatively serious".
In an impact statement, the victim said the assault had a major impact on his life.
"He had to move to his mother's place [and] couldn't eat solid food for six weeks. He had to put university on hold because of the medication he was taking.
"He says he feels like he can't spend time with friends or have any fun because of his need to focus on the recovery."
Judge Hastings accepted defence lawyer Cara Thorburn's submissions that it was an "impulsive, spontaneous assault".
It was a "disproportionate reaction to what was, though, a racist comment".
Leti has no criminal history and is in full-time employment.
His younger brother spoke in court, explaining how they had moved from house to house as children and often went without a father figure.
He said Leti had heavy expectations put on him as the eldest child, and described his Christian beliefs and his supportive role in his siblings' lives.
Leti has expressed remorse for the assault and pleaded guilty to injuring with intent to injure.
While Judge Hastings initially had a starting point of imprisonment for sentencing, when he factored in mitigating factors such as Leti's remorse, upbringing, and lack of criminal history, the end sentence dropped to one below one year of imprisonment.
Sentences below two years in prison can be substituted for another type of sentence if it is appropriate to do so.
Judge Hastings instead imposed six months of supervision.
He noted Leti had saved $2000 towards emotional harm reparation, but only ordered him to pay $1000.