async updateTgwRouteTable()

in functions/source/nic-attachment/lib/aws/index.js [3409:3523]
102 lines of code
10 McCabe index (conditional complexity)

    async updateTgwRouteTable(attachmentId) {
        let params, waitTimeStart, data;
        params = {
            Filters: [
                {
                    Name: 'transit-gateway-attachment-id',
                    Values: [attachmentId]
                }
            ]
        };
        let promiseEmitter = () => {
            return ec2
                .describeTransitGatewayAttachments(params)
                .promise()
                .catch(error => {
                    logger.warn(
                        'error in describeTransitGatewayAttachments ' +
                            `>${JSON.stringify(
                                error instanceof Error
                                    ? {
                                          message: error.message,
                                          stack: error.stack
                                      }
                                    : error
                            )}`
                    );
                });
        };
        let validator = result => {
            logger.debug(`TransitGatewayAttachments: ${JSON.stringify(result)}`);
            if (
                result &&
                result.TransitGatewayAttachments &&
                result.TransitGatewayAttachments.length > 0
            ) {
                // NOTE: by the time April 26, 2019. the AWS JavascriptSDK
                // ec2.describeTransitGatewayAttachments cannot properly filter resource
                // by resource-id. instead, it always return all resources so we must
                // do the filtering in the function here.
                // eslint-disable-next-line max-len
                // ref link: https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/EC2.html#describeTransitGatewayAttachments-property
                let attachmentFound = null;
                attachmentFound = result.TransitGatewayAttachments.find(attachment => {
                    return attachment.TransitGatewayAttachmentId === attachmentId;
                });
                logger.debug(
                    `attachmentFound: ${JSON.stringify(attachmentFound)}, ` +
                        `state: ${attachmentFound && attachmentFound.State}`
                );
                // need to wait for the attachment state become available
                return attachmentFound && attachmentFound.State === 'available';
            }
            return false;
        };

        let counter = () => {
            // force to end 30 seconds before script timeout.
            if (Date.now() < process.env.SCRIPT_EXECUTION_EXPIRE_TIME - 30000) {
                return false;
            }
            let waitTimeSec = (Date.now() - waitTimeStart) / 1000;
            logger.error(
                `VPN attachment cannot become available within ${waitTimeSec}` +
                    ' seconds. Update failed.'
            );
            return true;
        };

        try {
            waitTimeStart = Date.now();
            // wait until transit gateway attachment become available
            data = await AutoScaleCore.Functions.waitFor(promiseEmitter, validator, 5000, counter);
            // update
            let outboutRouteTable = await this.platform.getSettingItem(
                'transit-gateway-route-table-outbound'
            );

            // add transit gateway route association to the inbound route table so all traffic
            // going back to the TGW from any FGT will be routed to the right route (propagation)
            // TODO: use the latest this._settings[] method
            let inboutRouteTable = await this.platform.getSettingItem(
                'transit-gateway-route-table-inbound'
            );

            let [propagationState, associationState] = await Promise.all([
                this.platform.updateTgwRouteTablePropagation(attachmentId, outboutRouteTable),
                this.platform.updateTgwRouteTableAssociation(attachmentId, inboutRouteTable)
            ]);

            logger.info(
                'transit gateway route table updated. ' +
                    'time used: ' +
                    `${(Date.now() - waitTimeStart) / 1000} seconds.` +
                    `propagation state: ${propagationState}, ` +
                    `association state: ${associationState}.`
            );
            return {
                attachmentId: attachmentId,
                propagationState: propagationState,
                associationState: associationState
            };
        } catch (error) {
            data = null;
            logger.error(
                JSON.stringify(
                    error instanceof Error ? { message: error.message, stack: error.stack } : error
                )
            );
            logger.error(
                'failed to wait for the transit gateway attachment ' +
                    `(id: ${attachmentId}) to become available.`
            );
        }
        return data;
    }