function create()

in apps/mountebank-mock/mountebank-source/src/models/smtp/smtpServer.js [13:96]
76 lines of code
7 McCabe index (conditional complexity)

function create (options, logger, responseFn) {
    const connections = {},
        SMTPServer = smtpServer.SMTPServer,
        server = new SMTPServer({
            maxAllowedUnauthenticatedCommands: 1000,
            disableReverseLookup: true,
            authOptional: true,
            onConnect (socket, callback) {
                const name = helpers.socketName(socket);

                logger.debug('%s ESTABLISHED', name);

                if (socket.on) {
                    connections[name] = socket;

                    socket.on('error', error => {
                        logger.error('%s transmission error X=> %s', name, JSON.stringify(error));
                    });

                    socket.on('end', () => {
                        logger.debug('%s LAST-ACK', name);
                    });

                    socket.on('close', () => {
                        logger.debug('%s CLOSED', name);
                        delete connections[name];
                    });
                }
                return callback();
            },
            onData (stream, socket, callback) {
                const request = { session: socket, source: stream, callback: callback },
                    clientName = helpers.socketName(socket);

                try {
                    smtpRequest.createFrom(request).then(simpleRequest => {
                        logger.info(`${clientName} => Envelope from: ${JSON.stringify(simpleRequest.from)} to: ${JSON.stringify(simpleRequest.to)}`);
                        logger.debug('%s => %s', clientName, JSON.stringify(simpleRequest));
                        return responseFn(simpleRequest);
                    }).then(response => {
                        if (response) {
                            logger.debug('%s <= %s', clientName, JSON.stringify(response));
                        }
                        return Promise.resolve(true);
                    }).then(() => Promise.resolve(request.callback()))
                        .catch(error => {
                            logger.error('%s X=> %s', clientName, JSON.stringify(errors.details(error)));
                        });
                }
                catch (error) {
                    logger.error('%s X=> %s', clientName, JSON.stringify(errors.details(error)));
                }
            }
        });

    return new Promise((resolve, reject) => {
        server.on('error', error => {
            if (error.errno === 'EADDRINUSE') {
                reject(errors.ResourceConflictError(`Port ${options.port} is already in use`));
            }
            else if (error.errno === 'EACCES') {
                reject(errors.InsufficientAccessError());
            }
            else {
                reject(error);
            }
        });

        server.listen(options.port || 0, options.host, () => {
            resolve({
                port: server.server.address().port,
                metadata: {},
                close: callback => {
                    server.close(callback);
                    Object.keys(connections).forEach(socket => {
                        connections[socket].destroy();
                    });
                },
                proxy: {},
                encoding: 'utf8'
            });
        });
    });
}