How long should rear air shocks last before leaking oil?

What is your question?

One rear shock has oil leaking, but air suspension does not seem to be a problem. When I had tires replaced, I was told that I had a leaking shock. I had previously seen that while replacing brake pads, so I have a pair of the shocks. If I wait to replace them, will the air compressor for these air shocks also need replacing?