Filter Log Data and get just the filtered data

Log Data can be filtered by making a post request to /api/filter with a json body in the following format:
{
    "filter" : {
        "activity" : [list of activities],
        "application" : [list of applications],
        "user" : [list of usernames],
        "time" : ["start time","end time"],
        "parameters" : {
            "keys" : [list of keys],
            "pairs": { key-value pairs. Eg. "teacher":"X","level":"5" }
        }
        "extras" : {
            "keys" : [list of keys],
            "pairs": { key-value pairs. Eg. "teacher":"X",{level":"5" }
       }
    }
}