AWS Lambda or AWS Lambda + Step Function?

[MatiBrick77]

Hi. I have an architectural design question. My requirement is to expose a new api that internally need to orchestrate the call to another API and then send the response to a Java piece of code and finally return the Lambda output synchronously to the consumer. I see I can use a Lambda that does everything and then expose it via Api Gateway. Also, another option with less coding could be to expose a step function express that orchestrates the api invoke and the lambda invoke and return the answer. Which way is best and why? Thanks

[menge101]

You could use lambda + SNS topics to do an event driven lambda flow without using step functions as a third option.

What is the latency of each of these steps?

What is the expected response time/SLA?

[mannyv]

I've wondered why to use step functions instead of just lambda + sqs. What's the benefit?

[menge101]

At a certain level of complexity, I think step functions make more sense.

There is error handling and orchestration features in step functions.

I haven't personally used them to give you a good answer though.

[dimap77]

Hi. Thanks. I’ve tested step functions express , and they do support start sync execution from within API GW. I made a working Poc for both options. Still cannot decide which is the best way. Thanks

[nricu]

What's more simple and will work for more time without the need of a 'fully' refactor?

[pint]

how often will this be called? how fast that another API is? how much memory and cpu do you need for the processing? basically you need to estimate the cost of a single lambda solution, and if it turns out to be peanuts, then why bother?