The application must be made upon affidavit, stating:
(1) The nature of the offense charged.
(2) The state of the proceedings in the action.
(3) The name and residence of the witness, and that his testimony is material to the defense of the action.
(4) That the witness is about to leave the state, or is so sick or infirm as to afford reasonable grounds for apprehending that he will not be able to attend the trial.