You can use your API 12 Million times per year and pay AWS $0

AWS Lambda

🧞 An AWS Lambda function is flexible:

• As of Nov. 2018, you can write in any language — even the 1959 language Cobol!
• You can trigger the code to run from a database action, an API query, a metric in CloudWatch, a 3rd party monitoring app, an IoT device…
• Even though a Lambda’s max timeout is 15 minutes, it can trigger another Lambda. So you can even do DNA sequencing with Lambda.
• You’re not locked into AWS. A Lambda just has the core logic — no server configurations. Google Cloud, Azure, and IBM have cloud functions too.

💸 An AWS Lambda function can be cheap :

• You can run your code 1 Million times per month for free, forever. That’s enough for many businesses, especially startups.
• You only pay for the milliseconds it’s in use for, instead of paying 24/7 costs for a server, not to mention IT staff.
• AWS has been around since 2006 and has never raised costs. Prices keep falling dramatically.

🏃 An AWS Lambda function makes you agile:

• Even if it doesn’t reduce your costs, because you have billions of users, the speed of development is worth it. Think of all the developer hours saved.
• Imagine how much faster you can try out ideas with customers.

🍀 And yes, a Lambda can run Spring Boot.

Get a Sample Spring Boot API Running in 5 Minutes

1. Prerequisites.
2. Clone the code from GitHub.
3. Build it with Maven.
4. Deploy it to AWS.
5. 🐶 Test it by going to the API’s URL and getting back a JSON of dog names.

Prerequisites

• Install Node.
• Install the serverless CLI: npm -g install serverless
• Install the maven CLI. If you have brew, it’s brew install maven.
• Set up an AWS account.
• Save your AWS credentials locally.

🐑 Clone the Code 🐑

This was written by AWS Labs, and then I converted the Spring Boot Pet Store example from SAM to the Serverless Framework. I wrote about how that reduced deployment complexity by 97.4%.

  
git clone https://github.com/serverless-guru/aws-serverless-java-container.git
  

🚜 Build It With Maven

  
cd samples/springboot/pet-store
mvn package
  

🚀 Deploy the API

  
sls deploy
  

Watch out for the output in your command-line. You should see something like this:

  
endpoints:
  ANY - https://rbzh9fj8q1.execute-api.us-west-2.amazonaws.com/dev/
  

⚗️ Test It

Paste that endpoint URL into your browser and add pets at the end, so .com/dev/pets. If it’s a success, then congratulations. If not, then leave a comment.

Anatomy of a Spring Boot Lambda

Just as with any Lambda, you can take advantage of CloudWatch Logs to print debugging messages. 🐛

The entry point to any Lambda accepts arguments, including the event that triggered it (the inputStream). This one is in the StreamLambdaHandler.java:

  
public void handleRequest(InputStream inputStream, OutputStream outputStream, Context context)
  throws IOException {
    handler.proxyStream(inputStream, outputStream, context);
}
  

What kind of Java things have you done in Lambda?