Should messages that will be shown to the client be shown from the client-side or from the server-side? Any (dis)advantages that you can think of between the two approaches?

If the we maintain sensitive information and different sets of data is maintained by users with different sets of roles, would exposing all the message templates in the client-side be security a issue?

Client side:

httpService.post('/someEndpoint', requestBody)
  .subscribe(json => {
    if(json.errorCode) {
      // the error service will retrieve the error template
      // for such errorCode and replace placeholder with
      // values from the requestBody
      errorService.alert(json.errorCode, requestBody);
    }
  });

Server side:

if(hasErrors) {
  // sets the response error code and error message
  apiResponse.error(errorCode, requestBody);
}

Client callback:

httpService.post('/someEndpoint', requestBody)
  .subscribe(json => {
    if(json.errorCode) {
      errorService.alert(json.message);
    }
  });

What do you think?