Function filter

lib/index.es.js:3958–4014

(changesHandler, opts)

}

function filter(changesHandler, opts) {
  var callback = opts.complete;
  if (opts.filter === '_view') {
    if (!opts.view || typeof opts.view !== 'string') {
      var err = createError(BAD_REQUEST,
        '`view` filter parameter not found or invalid.');
      return callback(err);
    }
    // fetch a view from a design doc, make it behave like a filter
    var viewName = parseDesignDocFunctionName(opts.view);
    changesHandler.db.get('_design/' + viewName[0], function (err, ddoc) {
      /* istanbul ignore if */
      if (changesHandler.isCancelled) {
        return callback(null, {status: 'cancelled'});
      }
      /* istanbul ignore next */
      if (err) {
        return callback(generateErrorFromResponse(err));
      }
      var mapFun = ddoc && ddoc.views && ddoc.views[viewName[1]] &&
        ddoc.views[viewName[1]].map;
      if (!mapFun) {
        return callback(createError(MISSING_DOC,
          (ddoc.views ? 'missing json key: ' + viewName[1] :
            'missing json key: views')));
      }
      opts.filter = evalView(mapFun);
      changesHandler.doChanges(opts);
    });
  } else if (opts.selector) {
    opts.filter = function (doc) {
      return matchesSelector(doc, opts.selector);
    };
    changesHandler.doChanges(opts);
  } else {
    // fetch a filter from a design doc
    var filterName = parseDesignDocFunctionName(opts.filter);
    changesHandler.db.get('_design/' + filterName[0], function (err, ddoc) {
      /* istanbul ignore if */
      if (changesHandler.isCancelled) {
        return callback(null, {status: 'cancelled'});
      }
      /* istanbul ignore next */
      if (err) {
        return callback(generateErrorFromResponse(err));
      }
      var filterFun = ddoc && ddoc.filters && ddoc.filters[filterName[1]];
      if (!filterFun) {
        return callback(createError(MISSING_DOC,
          ((ddoc && ddoc.filters) ? 'missing json key: ' + filterName[1]
            : 'missing json key: filters')));
      }
      opts.filter = evalFilter(filterFun);
      changesHandler.doChanges(opts);
    });
  }
}