My aunt made something similar with sliced cucumbers, tomatoes, onions, garlic, fresh dill, whole black peppercorns, salt, sugar and vinegar. Horseradish/currant leaf were added to make cucumbers crunchy.
My aunt preserve her salad for the winter. She had it all put in glass jars. She would pour hot water over the salad in the jar, process for 10 minutes in a boiling water bath before closing the lid. She would put jars upside-down until cool.
During the winter the salad was tasting almost as fresh. Some oil to serve...
This lady on youtube shows similar preparation, except she is using microwave instead of processing it in a boiling water bath.
https://www.youtube.com/watch?v=l19neL5hFGc