Notes on using Cognito with Serverless

  • event.requestContext.identity.cognitoIdentityId should be the user id
  • Cognito User Pools are for handling user registration, authentication, and account recovery
  • Cognito Identity Pools (or Cognito Federated Identities) are a way to authorize users to directly use the various AWS services in your account, such as S3, DynamoDB, and, most relevant for APIs, API Gateway

CloudFormation in serverless.yml

# What is that
# ============
# This script will help you setting up your digital ocean
# infrastructure with Ansible v2.0+ and DO API v2
# Usually, when working with DO, one is supposed to use
# inventory file, and spin up instances in a playbook.
View write.js
var fs = require("fs");
var path = require("path");
var outfile = path.resolve(__dirname, "appPrefs.json");
var lockfile = outfile + ".lock";
var data = "some data or other";
// obtain an exclusive read/write file handle on the semaphore file, "wx+", function (err, fd) {
if (err) {

Tweet help

  • Great @NodeDC meetup @socialtables ty @NodeSource @Hired_HQ for sponsoring
  • ty @socialtables @NodeSource @Hired_HQ for sponsoring @NodeDC


Use these links! Sign up for Hired if you haven't already!

View memory.js
var heapdump = require('heapdump');
var FeedParser = require('..');
var fs = require('fs');
var feed = __dirname + '/feeds/intertwingly.atom';
var ct = 10000;
var premem = process.memoryUsage().heapUsed;
if (process.env.HEAPDUMP) heapdump.writeSnapshot();
console.log("Pre: %s", premem);
View 20nginx-https-redirect.config
command: perl -0777 -pe 's#(listen 8080;\n)#$1\n if (\$request_uri = "/health") {\n set \$redirectFlag N;\n }\n\n if (\$http_x_forwarded_proto != "https") {\n set \$redirectFlag "\${redirectFlag}Y";\n }\n\n if (\$redirectFlag = "Y") {\n return 301 https://\$host\$request_uri;\n }#igms' -i /tmp/deployment/config/#etc#nginx#conf.d#00_elastic_beanstalk_proxy.conf
View Cargo.toml
name = "dining_philosophers"
version = "0.1.0"
authors = ["Dan MacTough <>"]
GITHUB_TOKEN=$(git config --global github.token) # I've defined an API token in my git config -- ymmv
GITHUB_USER="" # the collaborator
REPO_OWNER="" # the owner of the repos
REPOS="" # space-delimited list of repositories
PERMISSION="pull" # may be one of "admin", "push" (i.e., read/write -- default), or "pull" (i.e., read-only)
for REPO in ${REPOS} ; do
curl -X PUT -i -d '{ "permission": "'${PERMISSION}'" }' \
-H 'Accept: application/vnd.github.ironman-preview+json' \
-H "Authorization: token ${GITHUB_TOKEN}" \
#!/bin/bash -xe
# Unload nouveau
sudo rmmod nouveau
# Load nvidia
sudo modprobe nvidia
# Configure X
sudo nvidia-xconfig --use-display-device=None --virtual=1280x1024 --output-xconfig=/etc/X11/xorg.conf --busid=PCI:0:3:0 --enable-all-gpus
View canvas-to-image.js
function () {
window.requestAnimationFrame(function () {
const imgData = getImageFromCanvas();
// atob to base64_decode the data-URI
const imgSrc = atob(imgData.split(",")[1]);
// Use typed arrays to convert the binary data to a Blob
const buffer = new ArrayBuffer(imgSrc.length);
var view = new Uint8Array(buffer);
for (var i = 0; i < imgSrc.length; i++) {