When a defendant in a court of a magistrate in an action on contract does not appear and answer the plaintiff may file proof of the service of the summons and complaint or of the summons on one or more of the defendants and that no answer or demurrer has been served upon him. When the action is for the recovery of money only, judgment may be given for the plaintiff by default if the demand be liquidated. If (a) the claim be unliquidated, (b) the plaintiff itemize his account and append thereto an affidavit that it is true and correct and no part of the sum sued for has been paid by discount or otherwise, (c) a copy of such account and affidavit be served with the summons on the defendant and (d) the defendant shall neither answer nor demur, the plaintiff shall have judgment for the sum sued for as in the case of liquidated demands. In all other cases when the defendant fails to appear and answer the plaintiff cannot recover without proving his case.