The phrase "such a joy" is an idiomatic expression that means something brings great happiness or pleasure. It is often used to describe an experience or a person that brings joy and happiness to someone's life.
Usage examples
Spending the weekend outdoors with my family is such a joy.
Seeing my child's smiling face when they receive a gift is such a joy.
Reading a good book in peace and quiet is such a joy.
Watching a beautiful sunset by the beach is such a joy.
Having a loyal and loving pet is such a joy.
Seeing a loved one accomplish their goals is such a joy.
Enjoying a delicious meal with good company is such a joy.
Listening to my favorite music and singing along is such a joy.
Receiving unexpected compliments is such a joy.
Witnessing acts of kindness in the community is such a joy.
I recall that year with such joy; it was one of the best years of my life. (tinyhousegiantjourney.com)
Personally, I find such joy in clean sheets that I look forward all day to that first night of sinking down into the crisp, clean, cool sheets. (mindbodygreen.com)
Its always such a joy for me to see my own kids run and play in the same place where I grew up. (wishesandreality.com)