Alestic.com - A Personal AWS Blog by Eric Hammond

If you are using and depending on the TimerCheck.io service, please be aware that the entire code base will be swapped out and replaced with new code before the end of May, 2017.

Ideally, consumers of the TimerCheck.io API will notice no changes, but if you are concerned, you can test out the new implementation using this temporary endpoint: https://new.timercheck.io/

For example:

https://new.timercheck.io/YOURTIMERNAME/60

and

https://new.timercheck.io/YOURTIMERNAME

This new endpoint uses the same timer database, so all timers can be queried and set using either endpoint.

At some point before the end of May, the new code will be activated by the standard https://timercheck.io endpoint.

register today for this free conference with content organized and presented by AWS community experts!

The AWS user community in the Bay Area and (US) West Coast is getting together in San Francisco for a full day of technical content, food, drink, and mixing with other users in the AWS community.

At AWS Community Day San Francisco, the content is selected and planned by leaders in the AWS community, and all of the speakers are AWS experts from the West Coast community of AWS users, including some AWS User Group leaders and AWS Community Heroes.

Amazon is generously footing the bill for the event space, food, multi-media management, event site hosting, registration, and all the little details that make a big event like this go smoothly, but the content is organized and presented by AWS community leaders and experts, instead of Amazon employees.

“When we learn from the community we learn from others like us. We have a shared perspective as users of AWS. AWS Community Day will offer us a unique opportunity that we cannot get at AWS re:Invent or AWS Summit.”
– John Varghese, Leader, Bay Area AWS User Group

This free event is being held at the Marriott Marquis San Francisco on Thursday, June 15, 2017.

Breakfast, lunch, snacks, and happy hour are provided to keep the community fueled for learning and networking. Thanks, Amazon!

“I’m excited to spend a day learning and sharing with the rest of the AWS community. The sessions will be a great mix of practical tips about the services we use constantly, and showcases of new technologies that we aren’t so familiar with. It’s great to hear about best practices from Amazon, but it’ll be even better to learn from our peers’ real world results.”
– Ryan Park, Engineering Manager, Slack

There are eight sessions planned in two tracks, with plenty of valuable information for all types of AWS users, and lots of opportunities to meet others in the community and chat about your AWS experiences. The current agenda includes:

a small lesson learned in setting up a static web site with S3 and CloudFront

I created a static web site hosted in an S3 bucket named www.example.com (not the real name) and enabled accessing it as a website. I wanted delivery to be fast to everybody around the world, so I created a CloudFront distribution in front of the S3 bucket.

I wanted S3 to automatically add “index.html” to URLs ending in a slash (CloudFront can’t do this), so I configured the CloudFront distribution to access the S3 bucket as a web site using www.example.com.s3-website-us-east-1.amazonaws.com as the origin server.

Before sending all of the www.example.com traffic to the new setup, I wanted to test it, so I added test.example.com to the list of CNAMEs in the CloudFront distribution.

After setting up Route53 so that DNS lookups for test.example.com would resolve to the new CloudFront endpoint, I loaded it in my browser and got the following error:

Serving 2.1 million API requests for $11

Folks tend to be curious about how much real projects cost to run on AWS, so here’s a real example with breakdowns by AWS service and feature.

This article walks through the AWS invoice for charges accrued in November 2016 by the TimerCheck.io API service which runs in the us-east-1 (Northern Virginia) region and uses the following AWS services:

• API Gateway
• AWS Lambda
• DynamoDB
• Route 53
• CloudFront
• SNS (Simple Notification Service)
• CloudWatch Logs
• CloudWatch Metrics
• CloudTrail
• S3
• Network data transfer
• CloudWatch Alarms

During this month, TimerCheck.io service processed over 2 million API requests. Every request ran an AWS Lambda function that read from and/or wrote to a DynamoDB table.

This AWS account is older than 12 months, so any first year free tier specials are no longer applicable.

Total Cost Overview

At the very top of the AWS invoice, we can see that the total AWS charges for the month of November add up to $11.12. This is the total bill for processing the 2.1 million API requests and all of the infrastructure necessary to support them.

Today, Amazon announced a new web service named Amazon Polly, which converts text to speech in a number of languages and voices.

Polly is trivial to use for basic text to speech, even from the command line. Polly also has features that allow for more advanced control of the resulting speech including the use of SSML (Speech Synthesis Markup Language). SSML is familiar to folks already developing Alexa Skills for the Amazon Echo family.

This article describes some simple fooling around I did with this new service.

Deliver Amazon Polly Speech By Phone Call With Twilio

I’ve been meaning to develop some voice applications with Twilio, so I took this opportunity to test Twilio phone calls with speech generated by Amazon Polly. The result sounds a lot better than the default Twilio-generated speech.

The basic approach is:

1. Generate the speech audio using Amazon Polly.

2. Upload the resulting audio file to S3.

3. Trigger a phone call with Twilio, pointing it at the audio file to play once the call is connected.

Here are some sample commands to accomplish this:

1- Generate Speech Audio With Amazon Polly

live display of current event status for each stack resource

Would you like to be able to watch the progress of your new CloudFormation stack resources like this? (press play)

That’s what the output of the new aws-cloudformation-stack-status command looks like when I launch a new AWS Git-backed Static Website CloudFormation stack.

It shows me in real time which resources have completed, which are still in progress, and which, if any, have experienced problems.

stack creates new AWS resources unless user specifies pre-existing

Background

I like to design CloudFormation templates that create all of the resources necessary to implement the desired functionality without requiring a lot of separate, advanced setup. For example, the AWS Git-backed Static Website creates all of the interesting pieces including a CodeCommit Git repository, S3 buckets for web site content and logging, and even the Route 53 hosted zone.

Creating all of these resources is great if you were starting from scratch on a new project. However, you may sometimes want to use a CloudFormation template to enhance an existing account where one or more of the AWS resources already exist.

For example, consider the case where the user already has a CodeCommit Git repository and a Route 53 hosted zone for their domain. They still want all of the enhanced functionality provided in the Git-backed static website CloudFormation stack, but would rather not have to fork and edit the template code just to fit it in to the existing environment.

What if we could use the same CloudFormation template for different types of situations, sometimes pluging in pre-existing AWS resources, and other times letting the stack create the resources for us?

Solution

publishing new blog posts with “git push”

For the curious, the Alestic.com blog has been running for a while on the Git-backed Static Website Cloudformation stack using the AWS Lambda Static Site Generator Plugin for Hugo.

Not much has changed in the design because I had been using Hugo before. However, Hugo is now automatically run inside of an AWS Lambda function triggered by updates to a CodeCommit Git repository.

It has been a pleasure writing with transparent review and publication processes enabled by Hugo and AWS:

• When I save a blog post change in my editor (written using Markdown), a local Hugo process on my laptop automatically detects the file change, regenerates static pages, and refreshes the view in my browser.

• When I commit and push blog post changes to my CodeCommit Git repository, the Git-backed Static Website stack automatically regenerates the static blog site using Hugo and deploys to the live website served by AWS.

even though aws-cli is not available by default in AWS Lambda

The AWS Lambda environments for each programming language (e.g., Python, Node, Java) already have the AWS client SDK packages pre-installed for those languages. For example, the Python AWS Lambda environment has boto3 available, which is ideal for connecting to and using AWS services in your function.

This makes it easy to use AWS Lambda as the glue for AWS. A function can be triggered by many different service events, and can respond by reading from, storing to, and triggering other services in the AWS ecosystem.

However, there are a few things that aws-cli currently does better than the AWS SDKs alone. For example, the following command is an efficient way to take the files in a local directory and recursively update a website bucket, uploading (in parallel) files that have changed, while setting important object attributes including MIME types guessing:

aws s3 sync --delete --acl public-read LOCALDIR/ s3://BUCKET/

The aws-cli software is not currently pre-installed in the AWS Lambda environment, but we can fix that with a little effort.

starting with Hugo!

A week ago, I presented a CloudFormation template for an AWS Git-backed Static Website stack. If you are not familiar with it, please click through and review the features of this complete Git + static website CloudFormation stack.

This weekend, I extended the stack to support a plugin architecture to run the static site generator of your choosing against your CodeCommit Git repository content. You specify the AWS Lambda function at stack launch time using CloudFormation parameters (ZIP location in S3).

The first serious static site generator plugin is for Hugo, but others can be added with or without my involvement and used with the same unmodified CloudFormation template.

The Git-backed static website stack automatically invokes the static site generator whenever the site source is updated in the CodeCommit Git repository. It then syncs the generated static website content to the S3 bucket where the stack serves it over a CDN using https with DNS served by Route 53.

I have written three AWS Lambda static site generator plugins to demonstrate the concept and to serve as templates for new plugins: