once
كَانَ النَّبيُّ صلى الله عليه وسلم إِذَا أَتَاهُ أَمْرٌ يَسُرُّهُ أَوْ يُسَرُّ بِهِ خَرَّ سَاجِداً شُكْراً لِلَّهِ تَبَارَكَ وَتَعَالَى
Meaning
The Prophet PBUH would prostrate in gratitude to Allah upon receiving news which pleased him or which caused pleasure.
Source and references
Hisn al-Muslim, entry 242.The reference is copied from the edition; separate editorial verification is not complete yet.
Source edition: Fortress of the Muslim. Open source ↗