Help with fitting a front gate to brick posts required

[Daisyonok]

Could anyone help me with the following: we found the wrought iron gate that clearly used to be at the front of our house at the back of the garden when we moved in, and are keen to refit it to the gate posts at the front. We literally just have the gate - no fittings remain on the brick pillars. Additionally we would be interested in having it self-closing (spring loaded?) since we are getting a dog soon and don't want it running on to the road when people come to the door! We are in Herne Hill.

Many thanks.