recoder-code/collaboration-service/node_modules/sharedb/lib/client/snapshot-request/snapshot-request.js

Complete AI-powered development platform with ML model training, plugin registry, real-time collaboration, monitoring, infrastructure automation, and enterprise deployment capabilities

var Snapshot = require('../../snapshot');
var emitter = require('../../emitter');

module.exports = SnapshotRequest;

function SnapshotRequest(connection, requestId, collection, id, callback) {
  emitter.EventEmitter.call(this);

  if (typeof callback !== 'function') {
    throw new Error('Callback is required for SnapshotRequest');
  }

  this.requestId = requestId;
  this.connection = connection;
  this.id = id;
  this.collection = collection;
  this.callback = callback;

  this.sent = false;
}
emitter.mixin(SnapshotRequest);

SnapshotRequest.prototype.send = function() {
  if (!this.connection.canSend) {
    return;
  }

  this.connection.send(this._message());
  this.sent = true;
};

SnapshotRequest.prototype._onConnectionStateChanged = function() {
  if (this.connection.canSend) {
    if (!this.sent) this.send();
  } else {
    // If the connection can't send, then we've had a disconnection, and even if we've already sent
    // the request previously, we need to re-send it over this reconnected client, so reset the
    // sent flag to false.
    this.sent = false;
  }
};

SnapshotRequest.prototype._handleResponse = function(error, message) {
  this.emit('ready');

  if (error) {
    return this.callback(error);
  }

  var metadata = message.meta ? message.meta : null;
  var snapshot = new Snapshot(this.id, message.v, message.type, message.data, metadata);

  this.callback(null, snapshot);
};